Crystal Ball Volume 20 - Dec 2010

NEW ZEALAND MOUNTAIN SAFETY COUNCIL

CRYSTAL 2010 BALL AVALANCHE MAGAZINE VOLUME 20

NEW ZEALAND EDITION NZ $12.00

PERIODICAL FOR THE NEW ZEALAND AVALANCHE COMMUNITY

DISCOVER MORE, SAFELY

NEW ZEALAND MOUNTAIN SAFETY COUNCIL

SOUTHERN HEMISPHERE

AVALANCHE CONFERENCE 11-12 JUNE 2011 COPTHORNE HOTEL COMMODORE CHRISTCHURCH AIRPORT

CHRISTCHURCH INTERNATIONAL SPEAKERS, LOCAL EXPERTS TWO PRE CONFERENCE WORKSHOPS: 10 JUNE AVALANCHE EDUCATION

2011

NZSAR AVALANCHE INCIDENT PRE-PLANNING

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info@mountainsafety.org.nz

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CONTENTS

04 05 06 08 09 10

CONVENOR’S VIEW AND PERSPECTIVES

AVALANCHE EDUCATION FOR 2010

AVALANCHE EXCHANGE, OTAGO GRADUATES 2010

BUSH CREEK BY RUSSELL CARR

BURIED BY AN AVALANCHE

REGIONAL SEASONAL SUMMARIES

22 25 31 33 36 37

AVALANCHE SEARCH DOGS

EARTHQUAKES AND AVALANCHES

THE HELMET DEBATE

THE OUTCOMES MODEL

THE WWW.AVALANCHE.NET.NZ RE-DEVELOPMENT

CRYSTAL BALL SUBSCRIPTIONS

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WELCOME TO SPRING

2010

WITH THE

NEW ZEALAND MOUNTAIN SAFETY COUNCIL

Welcome to the final issue of the Crystal Ball for 2010. This has been a very busy year for all involved with the Mountain Safety Council Avalanche Programme. We all breathed a collective sigh of relief at the end of the winter, after an avalanche fatality free season and hope this continues through the summer climbing period.

closed. Skier numbers at the club and commercial fields were down a little from last year but by all accounts, people heading out of bounds or into the backcountry were up. The international trend towards greater numbers of people venturing off piste seems to have been emulated here in New Zealand and the Mountain Safety Council is striving to communicate with these people on all levels. Good progress has been made on the re-development of the web site www.avalanche.net.nz and an exciting new model for the Info-ex. Both of these will offer the avalanche community the latest advances in computer technology and provide much more robust and interactive programmes. Planning for the Southern Hemisphere Avalanche Conference is well underway with a great line up of speakers and topics to inform and entertain.

But most importantly, the dinner menu and refreshment options have been sorted out and the raffle and spot prize pool is growing.

I hope everyone had a good winter and that you are enjoying whatever the off season brings you.

It was a variable year for snow- fall but nature still kept us on our toes. There was an early start to winter and a few incidents in the Southern Lakes region, then we progressed into a lean patch through the middle of the season, an Earthquake for the Canterbury region and finally the snow came, just as the ski areas and heli ski operations

Hobbie

THE CRYSTAL BALL December 2010 Issue 20 Vol 5 The Crystal Ball is created twice a year by the New Zealand Mountain Safety Council.

Submissions of articles, photographs and illustrations are welcomed.

Please send to:

For advertising enquiries contact:

ph: +64 3 371 3724 or fax: +64 4 385 7366 e: andrew.hobman@mountainsafety.org.nz 4 CRYSTAL BALL

ANDREW HOBMAN Avalanche Programme Manager

ph: +64 3 371 3724 or fax: +64 4 385 7366 e: andrew.hobman@mountainsafety.org.nz EDITOR: ANDREW HOBMAN DESIGNER: SAMANTHA CAIRD

+SNOW AND AVALANCHE CONVENOR’S VIEW:“PERSPECTIVES”+ Well what can I say about the 2010 Winter? It has been and left its

I consider myself a very motivated person and the role of Convenor of

mark. Many of us are probably reflecting on what was a pretty average

SAC is to have the big picture in mind and to drive strategic vision and

winter by now, whilst others have it as a distant memory as they head

direction for snow and avalanche related activities. Also I feel we are

for a Northern Hemisphere winter. The one thing that will stick in my

entering a new exciting era for the Snow and Avalanche Committee;

mind, is how harsh Mother Nature can be. Just when she seems to be

there are significant changes in the wind with some new very exciting

dealing the goods out, we get a rain event that brings us back down to

initiatives that we can adapt simply into our New Zealand system

earth. Typical of a developing La Nina pattern really! Looking from the

and environment. On the flip side, one of our biggest challenges is

glass half full, there was the odd day of great powder skiing mixed in

communicating effectively with backcountry users. This is something

that made it all worth while. You just had to be in the right place at the

that the whole snow based industry must take ownership of and

right time to get it. To me, that’s one of the reasons why avalanche

collectively address.

professionals are so passionate about what we do; sometimes we

The Convenor’s view will regularly be in every issue of the Crystal Ball.

just put ourselves in the right place to take advantage of the great

I would like to use this to discuss future initiatives or strategies and

conditions that Mother Nature provides, safely of course!!!

would welcome feedback, discussion and debate on any of the topics.

Taking over the Convenor’s role from Hamish McCrostie at the end of

Cheers

last winter initially came as a bit of a surprise to me, but in the same breath I felt honoured and excited to take on the challenge. Personally

Chief Executive Officer: DARRYL CARPENTER Chairman: ROSS MEDER THE MISSION OF MSC’S SNOW AND AVALANCHE COMMITTEE: To provide expert advice and support to the Council on appropriate strategies to foster public safety in snow environments To oversee the training, assessments and qualifications of instructors to ensure that national standards are maintained and enhanced

CHRIS EMMETT

To oversee the professional training programmes of all providers as required To monitor, research and review trends in snow and avalanche activities to ensure the Council remains the leading authority for safety in this environment All material produced by New Zealand Mountain Safety Council is considered to be in the public domain. As such, all materials may be reproduced for research or classroom use. Permission is also granted for use of short quotations, figures and tables in scientific books and journals.

PAINTING BY RICHARD TEUA TUROA SKI PATROL

+AVALANCHE EDUCATION FOR 2010+

benefited from the six Back Country courses. International statistics show that the numbers of people taking advanced recreational courses is about 10% of the number taking the entry-level courses and our totals mirror this. Having said this, we see plenty of room for

One of the Mountain Safety Council’s primary strategies for promoting

participant growth in both of these courses with a marked increase

people to get into the outdoors, safely, is the education programme.

in the Back Country course. We aim to achieve this through a more

The MSC Avalanche programme delivers and facilitates a progressive

co-ordinated national and international advertising campaign, the

syllabus from recreational one to four day courses through to the

redeveloped web site (www.avalanche.net) and by extending the

professional Stage 1 and 2 courses. The programme also maintains and

participant focus to groups such as hunters, SAR volunteers and DOC

revalidates the instructor pool and is involved with the development

staff. The Polytechnics and Outdoor centres around New Zealand

and moderation of course content.

handle the delivery of the professional level courses (Stage 1 and

The winter of 2010 was another successful year for education delivery.

2). This winter 114 participants were assessed for Stage 1 and Otago

The MSC branches and Ruapehu Alpine Lifts (RAL) ran 29 Avalanche

Polytechnic continued to successfully deliver the revised Stage 2

Awareness courses for 329 people, and 38 outdoor recreationalists

syllabus to eight new graduates.

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+THE NEW ZEALAND AVALANCHE INFORMATION EXCHANGE +

a Web-based (hosted) application that meets all of the criteria and more. They recognised that, just like us the avalanche industry in Canada required a programme that could reliably and accurately store and analyze snow science observations. Their application provides comprehensive date collection, real-time reports and custom charts, and dependable services. It has been used successfully in North America for the past 4 years and is fully tested, running and available

The Info-Ex provides a daily exchange of technical snow, weather, avalanche and terrain information between subscribers who actively manage avalanche hazards. The Info-Ex also serves as one of the key sources of data used by the MSC Avalanche Centre’s avalanche forecasters to produce and verify their daily advisories.

Over the past winter, we have been working hard at developing a model for a better information exchange between industries and professionals working in avalanche terrain. The existing system is based on the sound and underlying principle that sharing safety information is of a great benefit to organisations and the sector as a whole, by improving awareness of conditions across the region and enhancing the ability to manage local avalanche risks. Critical to this is that the data is accurate, relevant and real time. The MSC’s present system is at a critical point in its development and/or usability cycle.

The functionality of the site is not conducive to complete data entry and data analysis is restrictive. In addition, users are requesting features that are testing the limits of the current implementation (advanced integration of observations and locations) and its feature set (snow profiles, 3D mapping etc.).

The solution for many of these issues is to provide a web based tool that can efficiently record, store and analyze an operations safety data. This should be the primary vehicle for the recording of daily operational data to ensure a full and accurate data set. By using a “Cloud” or web based tool we can ensure that the system remains progressive and is in real time. It also allows the ability to share this information with other relevant operations. For industry, the documenting and sharing of safety information also satisfies any Department of Labour requirements.

Powdercloud are a Canadian company who have designed and run

for use by the New Zealand Industry. With other critical features like zero-maintenance, data security, and a whole lot more – Powdercloud provides a fantastic solution to our needs!

The MSC have negotiated a very cost effective partnership agreement with Powdercloud to provide access to their system for the New Zealand Industry. The licensing cost structure has been set up in a tiered fashion to balance the size of operations, the volume of data used and the desire to make the system financially viable to all of the operations, right down to the very small. Each individual subscriber will pay an annual license fee that provides them access to the full Powdercloud package to store, analyze and retrieve all their daily and historical data. The ownership of the data remains with the subscriber and they control who and how much data they share. Each subscriber sets up their own profile including avalanche path or run list names, staff involved, weather stations, oblique photos, control routes etc.

These are displayed in drop down lists to ensure quick data entry.

Weather, snowpack and avalanche observations can be stored as Meta and graphical data on 3D maps and can link between the two. i.e. you can mark the position of a snow pit on the 3D map, mouse over it for a dialog box or click on it to link with the built in Snow-profile tool.

MSC staff have been testing and demonstrating the system to the avalanche industry and presented it to the Ski Areas Association AGM in November. There has been very high interest in the product and we are now preparing the final documentation required to implement the system for New Zealand. Our hope is to have a high percentage of the New Zealand industry using the program for the 2011 winter.

For more information on the system, please contact Andrew Hobman at Andrew.hobman@mountainsafety.org.nz.

CONGRATULATIONS TO THE SUCCESSFUL AVALANCHE STAGE 2 GRADUATES FOR 2010.

OTAGO Polytechnic continues to deliver the new and improved syllabus to industry professionals. The redeveloped course incorporates a mentored logbook (Applied Snow Studies), three Theory courses, a 5-day Field Training (FT) course and a final 8-day Integrated Practical Assessment (IPA). The extended programme not only meets the needs of our NZ avalanche industry but brought us into alignment with international educational trends.

For information on the course, contact Barbara Emmitt (Avalanche Programme Administrator) at 0800 765 9276.

L-R: Karen Jackson, Chris Emmett, Wayne Carren (Instructor), Kevin Boekholt (Instructor), Pete Ozich, Tony Donaldson, Karen Corcoran and Julie Robertson. – Instructors not shown; Don Bogie, Tarn Pilkington, Mark Sedon and Peter Bilous.

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BUSH CREEK

Picture you will a sky of blue And a dessert-scape of snow When the chips are down and the going’s tough There’s only one place to go

It’s not to the North where the peaks are high And the fearless dare to tread Nor to the South where the skiing’s great But somewhere else instead

It’s a place I’ve come to really love A place to call my own For once you’ve done some skiing there You’ll really feel at home

Well some they laugh and some they cry And I’ve seen some that weep I don’t know why they feel that way It’s really not that steep

But it’s a place just out the back Not far from Coronet Peak I guess you know the name by now It’s simply called BUSH CREEK RUSSELL CARR - HARRIS MOUNTAIN HELI SKI

8

+BURIED BY AN AVALANCHE+ An incident which occurred at the Reefs, at Browning’s Pass, last

on which he felt the cold wind playing when the avalanche stopped. By

week, is worth mentioning, as it shows the time, it is possible for

the aid of the wind, which carried the snow away when he loosened it,

a human being to exist when buried in the snow. Messrs McAlpine,

he managed to dig himself out, and after shouting for Teague without

Bros, the well-known contractors of Sheffield, have undertaken a

getting any reply, he struck for the mine, where, after a desperate

contract from the Christchurch Gold mining Company to excavate a

struggle, he arrived in a state of collapse and utterly incapable of

drive – 1000ft or so – and, as they were bound to time, it was necessary

speech, until stimulants were procured. Once informed of the state

for them to work both day and night, through the winter, a thing not

of things, the younger McAlpine acted with promptitude, and started

usually done in consequence of the quantity of snow generally laying

to the camp for assistance, travelling down the bed of the stream

in the ranges. At the time of which I am speaking, there had been an

to avoid any fresh slips that might occur. He arrived there in a very

unusually heavy fall, and Mr George McAlpine and a man named Baird

short time, and after giving the alarm and changing his clothes – the

were at work in the drive. They were to be relieved at 12 p.m. by two

trousers of which had frozen hard- he headed the rescue party. All

men named Danks and Teague, who started from the camp– situated

hands turned out promptly, and, armed with long-handled shovels

a mile and a quarter from the mine – at 11.30 on their way to the

sought eagerly for their lost comrade till ten in the morning, when

works. To reach this it was necessary for them to follow up a gully,

giving up all hopes of ever seeing him alive, they adjourned to have

down which the head water of the Wilberforce flows, traversing a

some breakfast and make arrangements to have the corpse conveyed

path 190ft above the stream, which has been cut mostly out of the

to Springfield. Directly after breakfast another attempt was made to

solid rock. Some idea of the steepness of the country may be formed

recover the body. The rescuers must have suffered severely. All the

when it is stated that there is a rise of 600ft between the camp and

time there was a bitter cold wind blowing, which lifted the snow up

the mine. When Teague and Danks were some 300 yards from the

and carried it along in drifting, blinding clouds. The snow froze on the

drive, they came to a blind gully forming a sort of bay, round which

handles of the shovels they held to the thickness of a man’s thigh.

the road led. This had been so completely blocked by drifting snow

Their beards were frozen to their chests, and icicles hung from their

that it necessitated their ascending the mountain some distance to

hair and eyebrows – in fact, they were enclosed in armours of ice. Their

find a more practicable passage. Teague was just in the centre of the

attention was directed to a place 300 feet from where the slip occurred

gully, and Danks, who was in front, was nearly out of the drift, and

by a terrier belonging to Baird and George Mc Alpine, who had a 1/4in

was turning round to show his comrade the light of the lantern he had

rod of iron, managed, after trying for some time, to strike Teague on

with him, when there was a deafening roar, and they felt the snow

the leg. He was found at 12 o’clock lying on his back, unconscious, but

carrying them downhill at a rapid pace.

with his eyes open. His right arm was doubled under him, but the left was still working spasmodically, as if trying to dig himself out. He

PETER DANKS SEEMS TO HAVE DESCENDED FOR A HUNDRED AND FIFTY FEET, AND TO HAVE BEEN COMPLETELY COVERED WITH THE EXCEPTION OF ONE HAND, STRETCHED TO THE FULLEST EXTENT ABOVE HIS HEAD,

9 10 CRYSTAL BALL

recovered, and was doing fairly well in a couple of days, and wished to go to work. To this however, the contractors would not consent, but generously kept his time good for a week.

CANTERBURY TIMES 7 OCTOBER 1887

+2010 AVALANCHE.NET.NZ REGIONAL SEASON SUMMARIES+

Another winter season draws to a close as spring pushes itself once again into the October limelight. The past few months have not been without incident, but fortunately those that have had avalanche involvements, have come out unscathed, and we hope the wiser for the experience.

We are currently undergoing a development phase here at www. avalanche.net.nz, as we look to improve the methods and presentation of our avalanche advisories. Expect some exciting new things for next season as we roll out multi level advisories using text and graphics to best inform our viewers. There is much work to do through the summer months to get this ready, but for this year we would like to thank all the Ski Patrols and Guiding companies who, without their efforts, our Regional forecasts would not be possible.

We appreciate the time taken by these operations to make available their keen observations. This enables our Regional Forecasters to

RUAPEHU REGION // TARANAKI REGION NELSON LAKES REGION // ARTHUR’S PASS REGION // CRAIGEBURN REGION // MT HUTT REGION // ARROWSMITHS REGION // AORAKI REGION // MT COOK REGION // WANAKA REGION // QUEENSTOWN REGION

communicate key information for Backcountry travellers to use when making decisions.

Thanks also to our Forecasting team, who are scattered around the alpine areas of the country. We value their work tremendously, as they produce consistent, high standard avalanche forecasts, to help us all make informed decisions when travelling in the backcountry.

Below are a summary of each regions significant events and trends over the winter season. Enjoy the reading as well as the looming Spring touring season, and we hope to continue to cater to your needs.

We are always interested to hear your thoughts and comments, so please write to us and let us know how we are doing. All feedback is welcome. Please write to info@avalanche.net.nz.

Thanks

INFO@AVALANCHE.NET.NZ.

INFOEX COORDINATOR – GORDON SMITH

10

+TONGARIRO NATIONAL PARK RUAPEHU REGION+ WEATHER High pressure dominated the majority of July with only a few low pressure systems bringing small amounts of snow to the region and relatively cool temperatures. August was relatively unsettled with a continuing pattern of mid Tasman low pressure systems which generally brought warm Northwesterly flow followed by cool Southeasterly. Early August brought heavy rain showers to high elevations in the region with winds from the Northwest.

Mid August, continuing low pressure finally brought snow to low elevations in the region with storms depositing 10cm followed by another 20cm. As the pattern continued, warm Northwesterly flow deposited 60mm of rain to high elevations washing away large amounts of snow at lower elevations.

This pattern of unsettled weather continued through the end of August into September with snow showers to low elevations with high winds followed by heavy rain showers to high elevations generally losing more snow than was accumulated. Mid September brought a relentless low pressure system that enveloped the whole of New Zealand and continued to dominate the region with heavy snowfall to low elevations and gale force Northwesterly winds which persisted into the last week of September. This system left a trail of damage to the ski areas operating in the region with large accumulations of snow partially burying buildings and lift drive stations. Also many ski lifts derailed from severe gale force winds and intense ice build up that amounted to 5 feet on lifts and even caused the failure and collapse of a lift tower.

This pattern may continue into October.

SNOWPACK A generally stable snowpack existed throughout the majority of July with very few storms bringing small amounts of snow accumulating to low elevations leaving a relatively shallow snowpack. Cooler temperatures caused the growth of a near surface weakness in the snowpack on shady aspects late July but early August, heavy

11

12 CRYSTAL BALL

rain showers to high elevations saturated the snowpack nullifying previous weakness.

Mid August, low density snow fell to low elevations and cross loaded onto an array of slopes facing West through the North and East with pockets of sensitive slab up to 50cm deep in places. Heavy rain showers to high elevations quickly followed melting and consolidated the old snowpack leaving a generally stable pack consisting of wet grains and multiple crusts. These same showers washed away snow at lower elevations lifting the avalanche threshold to above 1800m.

Heavy snow showers persisted in the last week of August loading slopes facing the Easterly ½ with 80cm of sensitive soft slab at higher elevations. This quickly cross loaded onto to slopes facing the Southerly ½ and remained sensitive. Early September, heavy rain showers again saturated the snowpack to high elevations nullifying any previous weaknesses and causing the snow line to recede at lower elevations. Mid September saw the start of significant storm cycle that continued into the last week of September.

Gale winds from the Westerly ½ continued to load storm snow onto slopes facing the Easterly ½ above 1600m creating multiple layers of sensitive soft and hard slab which grew to over 3m deep in places. Deep instabilities remained a concern on these slopes on the days following however heavy rain showers to high elevations yet again saturated the snow surface and refroze leaving a very strong supportive widespread crust. Time settled out any remaining deep instabilities leaving a generally stable pack.

Snowpack observations will continue through October into early November.

2000m ranging in size from 1½ to 2½ sliding within the storm snow. 2 Climbers remotely triggered a small size 1 avalanche above 2300m from a distance of metres late August. Natural activity was expected late September however it didn’t eventuate.

AVALANCHE OBSERVATIONS Multiple Avalanches were triggered by Ski Patrollers on an array of aspects averaging from size 1 to 2½. The majority of these Avalanches were above 1800m and triggered with explosives while smaller slides were controlled with ski cutting. Natural activity was observed early to mid August above

BY DENHAM STEWART

DANGER RATING The Danger Rating spent little time on LOW this season with the majority of time spent fluctuating between MODERATE and CONSIDERABLE as storm cycles continued to pass over the region. The rating trended to HIGH for over a week in the last part of September as a significant storm dominated the region for 10 days but trended back to MODERATE by the end of September.

TRAVEL ADVISORY Backcountry Travellers were advised to use caution mainly on steep unsupportive slopes above 2000m on an array of aspects, occasionally lowering to 1800m as avalanche conditions existed throughout the season with storm snow being the main concern.

Late September was the most significant advisory, backcountry travel was not advised as the danger rating trended to HIGH as deep instabilities existed sensitive to the weight of a single skier and inclement weather conditions made safe route finding challenging for even experienced persons.

This advisory remained for over a week.

Currently alpine winter conditions still exist in the Mt Ruapehu/Tongariro region and daily forecasts will continue through October and into early November where from there on, intermittent advisories will be entered as significant hazards arise.

+NELSON LAKES REGION+

+TARANAKI REGION + THE WEATHER Winter struggled to make a start in Taranaki this year. We did receive some good snow falls which you could count on one hand but this was closely followed by very warm weather conditions where the freezing level would go close to the top of the mountain on many occasions. Starting from July our first good bit of winter weather happened around the second week where we received snow from the south east down to 1000m. This was followed by a warm settled period with varying temperatures before the end of the month brought more snow to low levels.

For the start of August the snow on the mountain didn’t fair too well with 110mm of rain recorded at 1400m on one day with more rain during the week. This weather decimated the mountain snowpack. This was followed by cool clear conditions before the next lot of warm rain on the mountain reduced the snowline to around 1900m. Towards the end of August we saw a return to some winter like conditions with snow falling to low levels.

The start of spring saw a mix of snow and rain across the mountain until the much talked about storm that crazed the country, and brought snow to low levels across the Taranaki region. Strong south westerly winds and snow as low as 500m hit the region during this storm, but unfortunately as the storm cycle came to an end we saw a rapid warm up with rain. The freezing level has climbed to around the top of the mountain and most of the snow received during this storm has gone.

THE SNOWPACK With such an up and down winter the snow pack had little time to accumulate into any mass below 1800m. As mentioned in the weather section we did receive several good snow falls with 20-30cm above 1400m at the end of July with moderate south easterly winds. For most of July the snow pack was well consolidated with multiple crusts within the pack. Come August what snow that the mountain had retained was hammered by

heavy rain across most of the mountain below 2100m. As conditions cooled following this rain, the snowpack became very firm.

20cm of snow fell over the last week of August above 1500m. September saw heavy snow fall to low levels with strong to gale force winds. Large pillows of snow formed on leeward aspects to the south west with significant weak layers buried within the wind transported snow. This was quickly eliminated as the rain came down a few days after this storm.

AVALANCHES Several avalanches have been recorded near the ski area on the mountain this year.

On both occasions these happened during the storm cycle with the larger avalanches happening in the September storm. If mountain users witness avalanches or debris please report to the local Mountain Safety Council or the Ski Area.

CONCLUSION The winter of 2010 in Taranaki was one to forget, with only a handful of operational days for the local ski area. Any snow that was received was immediately followed by rain which destroyed any hope of building a good base of snow. So conditions haven’t been great this winter for recreational activities on the mountain but those that did venture out kept safe. Looking forward to the coming weeks of spring; use general care as conditions will vary on the mountain from hard in the morning to soft in the afternoon.

Care will be needed around steep unsupported aspects in the afternoons as heat takes its toll on these slopes. Thanks to all of those that send in information and took the time to read the daily forecasts. Remember to be safe out there as the mountain will always be there tomorrow – make sure you are too, wait till the conditions are right.

BY TODD CATIONS-VELVIN

OVERVIEW This was the second winter that the Nelson Lakes Region had an Avalanche Advisory using Avalanche.net. This season has been disappointing for snow cover in the park with a large part of the early season with very minimal coverage. Rainbow is surrounded by excellent back country touring which is well know by local users but this season has seen little ski touring activity with mostly a small amount of slack country use directly around Rainbow Ski Area. The New Zealand Back Country Ski Guide refers to Rainbow as well as the quality of the terrain around Angelus Lake for back country touring so this year’s inactivity is an anomaly caused by lack of snow cover. DOC has posted the advisory on a daily basis at the St Arnaud park headquarters again this winter and has assisted the forecasting team with an occasional seat in a helicopter for over flight and snow pack observations.

The primary source of information is still the Rainbow Ski Patrols ongoing observations in the St Arnaud range on the eastern boarder of the national park. Secondary to that the NIWA meteorological site on the Mahanga range in the western side of the park sent twice daily automated emails to the forecasting team and access to the web based data was secured this winter which allows the team to view real time data with comprehensive weather information. This season Rainbow Ski Area has installed a Davis system with most of the valuable recordings required which was available real time from a web site. We still struggle to get avalanche observations from the western and southern part of the park due to its remoteness and lack of personnel in the area during winter.

WEATHER AND SNOWPACK. After approximately 60cm of snow in early June the weather conditions remained clear and calm for several weeks. The shallow snow pack and cold air temperature created a very weak snow pack similar to further south. The snow pack had very pronounced facets below

12

a brittle ice crust. This layer would have been very problematic with significant load and remained very prominent for some time.

Late June and July have seen long periods of settled weather interspersed by periods of disturbed westerly often associated with high freezing levels. Very little snow fell during this period. There was not significant snow fall until mid September by which time this layer had been strengthen by a number of rain events and warm air temperature. Mid and late September has seen a significant increase in snow cover with the strongest westerly airflow seen for some time. With approximately 120cm of new snow falling in the park associated with very strong winds from the westerly quarter, the avalanche danger was at considerable and high for some time. Density variation was the most common weakness during this time and one significant slab avalanche cycle occurred within the new snow during the storm.

The disturbed westerly has continued but a significant increase in temperatures and rain to high levels have produce a significant loose snow avalanche cycle on the 100926.

This was due to storm snow on eastern aspects becoming saturated. Warm moist conditions prevail at the time of writing this and loose snow activity is anticipated to be occurring as the month draws to a close.

Back country users will need to be aware that significant snow exists on eastern aspects and this may well continue to develop given the disturbed weather being experience during this spring so far. Caution will be required as spring continues due to snow volumes on these aspects. There has been no significant weakness noted recently within the snow but warm temperatures and rain will decrease snow strength and care will be required during those times.

AVALANCHE OCCURRENCES Only two significant avalanche cycles occurred this winter to date. The first was wind slab on approximately the 100920 on eastern aspects due to significant storm snow volumes, intense wind loading and precipitation intensity.

The second was a loose snow avalanche cycle on the 100926 due to a rain event to high elevation on northern and eastern aspects.

Prior to this the occasional loose snow avalanche and small wind slabs isolated to ridge crest occurred but not of any great significance.

13 14 CRYSTAL BALL

CONCLUDING REMARKS No avalanche involvements have been reported to the forecasting team from within the park at the time of this reports writing.

This is due in no small part to the lack of snow and hence backcountry use in the majority of the park. It has been reported that a class 3 slab avalanche was initiated remotely outside Mount Lyford’s ski area boundary in the early season but this remains unconfirmed. We still have work to do in the northern region of the South Island in terms of educating people about the avalanche phenomena and the use of Backcountry Avalanche Danger Advisory.

The success of this program continues to be possible due to the efforts of Rainbow Ski Areas professional Patrol department and the Rainbow Management Group as a whole. Access to the information from the Ski Areas Davis weather system has assisted the forecasting team greatly. Thanks again to NIWA for access to the Mahanga weather site information and the DOC for helicopter access to the park.

BY MATT WILKINSON

+ARTHUR’S PASS REGION+ OVERVIEW The Arthur’s Pass region was off to a slow start snow wise this season. July and August saw northwesterly flows from small disorganized storm cells which brought above average temperatures, wet weather and high winds from the north. In September things started to change to more normal weather patterns as large Antarctic systems began to come into our area bringing colder temperatures and more snow. At press time we are under the influence of large,well organized Antarctic low pressure systems which are bringing high winds from the northwest as the systems wrap around the island and much snow.

WEATHER Winter came a bit late this year and for July and most of August any snowstorms that we got were knocked right back down by rain storms that followed. July 21st storms brought about 30 cms of snow and on July 27th there was

another 35cms. It rained 125 mm on August 1st and 2nd followed by 10 cms of snow on August 7th. There was 175mm of rain over August 13th and 14th and 20 cms of snow on August 18th which caused some widespread avalanche activity. The end of August saw about 30 more centimeters of snow. The first few days of September brought about 40 cms of new snow giving skiers some hope that things might improve but, those hopes were washed away when a 200mm rainstorm on September 5th and 6th brought snowpack levels back down to the 35 cm level at 1400m. On September 3rd we had an earthquake. Then on September 17 it started snowing in earnest. The small disorganized storm cells that had been coming in from the northwest finally gave way to a much larger and more normal pattern of Antarctic air pushing up from the south. The result was that by September 21st we had more than a meter of new snow and it is still snowing at the time of this report. Although we did not have much snowfall near the beginning of the season we had quite a bit of wind resulting in the snow, particularly at high levels, being moved around ,collecting in gulleys and filling in between the rocks. The big rainstorms and cooler temperatures that we received washed away weak layers and helped to stabilize the snowpack before the big dumps arrived.

avalanches have been observed on the east face of Mt. Rolleston when we can see it. We are well into our second meter of snow since September 17th and it continues to snow.

Avalanche Danger on the Minga and other eastern aspects is HIGH.

SNOWPACK Early season snowpack below 1600m was below threshold through the first week in August. The snowpack above 1600 metres showed some distinct weaknesses in the early part of the winter. There were some very thin friable ice crusts at or near the surface that did not appear to have much strength.

Underneath this thin crust there was 20 to 30 cms of weakly bonded, unconsolidated snow that provided little support. To date, the most significant effect has been the extensive rain that we have received. Whereas there were some weaknesses in the snowpack before the rains and there were some avalanches caused by the rain, after the rain had stopped and the snow pack drained and temperatures cooled, the pack became super stable.

Subsequent snows along with high winds became well bonded and stable. It remains to be seen how much more new snow can fall before things start to slide again. There has been over a meter of new snow in the last week and nearly continuous gale force winds from the northwest. Therefore aspects lee to the northwest must be loading but so far no

CONCLUSION It was a stormy winter in Arthur’s Pass both with rain and a late charge of snow. There was a tremendous amount of wind and rain that eventually made for stable snow conditions.

Climbers got to climb some great ice and stable chutes,and now skiers are getting some great snow. No one was caught in a slide and it was, over all, a safe season. Many thanks to those who contributed observations and provided data across the region.

AVALANCHES During July there were some very thin ice crusts overlaying 20 to 30cms of unconsolidated snow above 1600 metres.

When 20 cms of new wet snow fell on top of these layers remarkably they did not collapse.

Instead avalanches occurred on top of the thin ice crusts (1cm) and did not step down to the nonsupporting layer. These slides started as very small fractures, maybe 10 cms deep, very high up on the slopes and by the time they reached the bottom of the run outs they had grown to size 3 and 4. Another phenomenon that occurred was when heavy rain washed over bare rocks and compounded the amount of water received by the snowpack below, led to deep slab avalanches.

There was the usual new wet snow point sloughs caused by solar radiation but the most unusual thing that occurred this winter was the earthquake on September 4th which caused cornices to fall on southeast aspects.

No resulting avalanches were recorded from this event.

BY STAN TENER

+CRAIGEBURN REGION+ OVERVIEW There’s a saying in New Zealand “Snow in June- still too soon”. Early falls of snow in May and June gave way to an extended period of high and dry in July. Local ski fields were able to open as planned and decent backcountry skiing could be found in the regions upper basins but snow coverings were thin and surface quality was average.

The odd shot of winter weather kept things going through to the usual seasons’ end but skiers were forced to make the most of a thin and weak snowpack for much of the season.

WEATHER Early periods of winter weather in May and June gave way to a dominating series of anticyclones with cool and mainly settled conditions persisting for much of July. A pattern shift in late July and August allowed for a series of cut-off lows (low pressure systems unassociated with the jet stream) to track NW to SE across the South Island. NW storm portions delivered more wind and rain than snow but lingering wrap around energy from the E and SE delivered significant falls of snow to low elevations on several occasions. A couple “more intense” westerly depressions late August and early September delivered severe winds and heavier falls of rain and snow to the range (85mm of rain to the top on 13 and 14 August, 40cm or so of snow over the last week of August and 65mm rainfall with 30-40cm of snow during the first 2 weeks of September). A significant pattern change mid to late September, (again a result of a shift in the tracking of the Southern Hemisphere’s ridges of high pressure) allowed a series of deep troughs to deliver an extended period of cold, severe W ¼ winds, and by far, the heaviest snowfalls of the season.

SNOWPACK A rain crust remnant from May’s deposits was eventually buried by snowfall on 22 June.

After a significant period of cold weather, the crust/ low-density snow combination developed into a weak faceted layer, which would be the dominant snowpack character in July and August. This faceted layer was especially tricky to track, being fairly wide spread across the high shady aspects, but as determined by the nature of the storm on 22

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June (where S ¼ winds scoured most snow near ridgeline) it was usually only found low in start zones and at the mid slope level)a recipe for disaster if stability was based solely on observations taken from high in the start zone. The 22 June faceted layer was eventually washed clean by rain on 13 and 14 August. The new (18 August) crust / lowdensity snow combo weakened quickly on upper elevation slopes of the S ¼- becoming the second significant persistent layer of the season. On 24 August, a layer of 4-8mm surface hoar became buried by falls of snow and graupel (mainly found on upper elevation slopes of the E ¼). This too would become a significant persistent layer in coming weeks.

A “rain to the top” event on 6- 9 September, and the eventual refreeze of the snows surface on 14 September would isolate any remaining weak, loose, or saturated snow existing at depth. From then, the snow would remain a more typical, well-bonded springtime pack, with instability being related more to storm snow inconsistencies and the freeze/ thaw cycle of the snow’s upper layers.

AVALANCHE OCCURANCES Junes’ faceted layer was responsible for a few natural occurrences (to size 2) from mid elevation S ¼ zones on 1 August. In the weeks that followed, backcountry skiers and boarders stayed mainly out of harms way but the snow pack’s dangerous nature was displayed by a few close calls and multiple reports of large slope settlements (whoomphing) associated with the 22 June layer. Numerous large (to size 3) natural occurrences were observed out of mid and upper elevation S ¼ zones after the 13 August rain event with some large debris observed to valley floor. The 18 August faceted layer

15 16 CRYSTAL BALL

and the 24 August surface hoar layer were first seen to react to the storm loadings of 2 September. Occurrences to size 3 were observed to have run to valley floor (from upper elevation E facing zones). During the fine weather that followed the 2- 3 September storm, it was believed that while natural avalanching was not as likely- there remained a real danger for large triggered avalanches.

The seismic jolt in the early morning hours of 4 September verified the tender nature of the snowpack. In the Craigieburn and Torlesse Ranges, numerous occurrences to size 3, mainly from E and SE zones ran to over a metre in depth and hundreds of metres wide on the buried persistent layers of August. Very large occurrences were also observed in the neighbouring Grey Rangeslabs to over 1000m wide involving entire basins. A significant cycle of triggered wet slabs occurred during the 6 September rain event and subsequent days of above zero temperatures. Controlled occurrences to size 2.5 were reported mostly out of mid elevation E ¼ zones, with significant occurrences reported from the W ¼ as well.

TRAVEL ADVISORY In spring, weather factors seem to have an amplified effect on stability. Snow and blowing snow can be fierce and temperature spikes can quickly loosen previously strong interfaces. During unsettled weather, storm snow and wind slab is usually the main concern- watch for storm weaknesses to be especially sensitive to the lee of ridgeline and features of the dominant wind direction.

If weather becomes intense, you’ll need to think about avoiding avalanche terrain all together. When the sun comes out, turn your focus to radiation related instability. Look

for signs of slopes preparing for a shedding of their winter coat (snowballing, lubricated feel underfoot) – that’s your que to retreat to lower angle terrain.

CONCLUDING REMARKS In New Zealand, its not often we’re exposed to such a lengthy period of old snow instability as was experienced this season. Snow coverings were for much of the season thin and inconsistent. On several occasions, harsh weather had its way with the snow cover- leaving a heavily wind and temperature sculpted surface. There was however plenty of opportunity for a quality backcountry experience. Low angle, shady terrain offered good powder stashes and August’s cold southerly storms deposited above average and generally well bonded coverings of snow on the ranges western faces. A season like this offers a good environment for learning about snow and an opportunity to practice using terrain to your advantage. Learning the subtleties of terrain, and its effect on stability will put the odds in your favor and allow you to travel across a wider variety slopes with greater safety. A quick thank you is in order to the mountain community of the Craigieburns. Much obliged to the many teams and individuals who contributed snow, weather, and avalanche information, vital to the cause. Information from ski area snow safety teams, ski guides, avalanche and mountain educators and of course recreational parties was irreplaceable.

Go Safely.

BY DAMIAN JACKSON

+MT HUTT/ARROWSMITHS REGION+ Overall the 2010 season was dominated by easterly winds for the early part of the season and strong NW winds for the latter.

The easterly produced a lot of cloud, snow and rain for the Mt Hutt part of the region with less snow near the divide. The temps were typically a lot warmer than usual with the freezing level around the 1700m mark causing a lot of storms to rain at Mt Hutt before the freezing level dropped during the storm. Mt Hutt was dominated by southerly weather systems for the first 4 months of the season. Significant snowfalls came late in the months of May, June, and July all from the southwest to the southeast. The low easterly cloud persisted above the Canterbury plains so on a number of days you could head up out of the cloud to Mt Hutt or The Arrowsmiths for a blue sky, calm day of great skiing or riding. The largest snowfall for Mt Hutt came on Aug 7-8th where in a 30 hr period Mt Hutt received over 1m of new snow from a classic SE storm. The rime crusts of most significance were buried on July 20th, July 31st, and Aug 13th with avalanche activity occurring on all crust layers in the Arrowsmith region. The cloud also helped produce a lot of surface hoar, with a number of observations made with concern about the new snowfall on top. There were regular observations of 2cm surface hoar but most layers were broken down by the rain at the start of the following storm. The most significant surface hoar layer was buried on Aug 17th and this played a part in the Sept 4th earthquake event avalanche cycle. Late Sept and early Oct saw the start of the spring westerly cycle that seemed to last forever. Strong winds and heavy precipitation brought an estimated 5+ metres of snow over 2 weeks to areas close to the divide at higher elevations. Winds were gale to severe gale force throughout the whole period with the odd welcome day with less wind. The snowpack was challenging this season. As mentioned above Mt Hutt often received rain as part of the storm cycle and would finish with rime leaving hard surfaces.

It also aided facet growth and caused a number of avalanche events both around Mt Hutt and in The Arrowsmiths to occur days after the storm.

An overall shallow snowpack in The Arrowsmiths caused facet growth that remained a player late into the season due to

the lack of heavy precipitation from NW storms. It wasn’t until the mid Sept warming trend and following the freeze that we felt the deeper instabilities were finally non reactive. It was a season of lots of digging for facet layers and hunting for the surface hoar that was observed before the snowfalls but often not found afterwards, the result of storms starting warm and destroying the surface hoar layers of concern.

ARROWSMITH In The Arrowsmith region the usual storm avalanche cycles occurred with some paths joining on facets/rime crust to size 3.5 in events never witnessed before.

The most relevant skier triggered event occurred on Sept 11th with an avalanche occurring on a north facing run - a hard 2cm crust failed into moist facets. No one was injured but this was a timely reminder to stay patient until the whole snowpack had frozen and not rely on bridging layers. Mt Hutt had an explosives triggered size 2.5 avalanche which buried the road on July 24th.

This was another example of the significance of the rime crusts as the avalanche stepped

down onto the lower buried crusts. The South Face was triggered post control on Aug 10th, which was an unusual event as it occurred in a place never witnessed before on lower angle terrain compared to where the avalanche control work had been undertaken.

This prompted 2 Land SAR avalanche search dogs to be deployed due to conflicting information from witnesses , the debris was cleared quickly and a car park count confirmed no one was missing. The size 7.2 earthquake on Sept 4th caused a widespread avalanche cycle throughout the whole region.

Most observations were on SE aspects and suspected on the Aug 17th surface hoar layer. Another part of the cycle occurred below 1700m on north aspects. This made for an interesting time looking around at how significant the earthquake was. Very little of the season seemed to be low danger, and care was required when travelling into the backcountry. Backcountry users seemed to be up on last year, with no incidents possibly indicating educated care in timing and use of terrain by these users. This is positive to see and may it continue into next season.

BY JAMIE ROBERTSON

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+AORAKI / MT COOK REGION+ The beginning of the 2010 season followed a similar pattern to last year, early snowfall, shallow snowpack followed by fine cold weather promoting faceting and surface hoar development. The fine spell broke on the 20th July and the subsequent few days of poor stability saw the first of many avalanches running on the 19th July facets. Each subsequent storm resulted in avalanching both within storm snow and on the 19 July layer. Notable avalanche cycles to size 3 occurred on the 26th July - 1 & 2nd August and the 13th August during periods of intense precipitation. Many avalanches were observed to run to valley floor during these cycles but the extent of debris was not as great as last year. Stability rated good for the first time in over a month on 23rd August by which time it was felt that, even though the July 19th layer could still be found well preserved beneath a strong crust on undisturbed low angle slopes, it had been destroyed on all possible avalanche terrain.

Storms at the end of August and early September were generally weaker than mid winter events, freezing levels occasionally crept up with some rain events above 2000m.

A couple of reasonable avalanche cycles happened on the 26th - 28th August and 6th September with slides up to 2.5 generally failing to overrun the extent of previous debris. Interestingly the 26th August slides had many size 2 avalanches initiating around the 1900m mark, the same altitude where the previous snowfall/ old surface had tapered down to “dust on a crust” By the 28th with a bit more snow and wind the size and altitude went up a bit and pretty much the whole S face of Hochstetter Dome fell off.

16th September saw a return to winter conditions with the onset of a very large lowpressure system bringing strong Westerly winds and snowfall to low levels. Precipitation was not especially intense during this period with the maximum 24 hour rainfall only

17 18 CRYSTAL BALL

43mm but the prolonged cold and windy nature of the storm has led to a huge amount of snow transport and some good size 3 avalanches observed to have run to valley floor in the Hooker. It is presumed that other widespread avalanching occurred but bad weather meant limited obs and those crown walls that could be seen were soon covered by drifting snow. An instructive demonstration of the effects of cross loading was seen in the timing of two of the Hooker valley events. On the 20th September after 4 days of W to NW winds and around 1m of snow on the divide the Hayter Stm. Avalanche path ran right down to the Hooker Lake. The neighbouring Stocking Stm path, which threatens the approach to Sefton bivvy, hung in till the next day when a wind shift to the SW delivered titanic amounts of snow from the up wind fetch area of the Huddleston gl overloaded the slope and brought down another solid size 3 slide. It’s not the first time this has been seen and is worth bearing in mind for those chasing the tail end of a storm in there to climb Footstool.

Ridge gl. He remained on the surface. On the 9th August two snowboarders were hit from above by a size 2 slab triggered remotely by a photographer traversing unexpectedly above them. They were swept 200m down steep but open terrain and remained on the surface. This was the only human triggered event on the July 19th layer, which at the time and place of the slide was capped by a strong 10cm crust with 40cms loose dry powder on top. The 50m wide slab was the last remaining pocket in an area that had otherwise been well stirred by previous avalanching. On the 14th September a ski tourer accidentally triggered a size 1 slab on the cornice wall (east aspect) following a small dump with some westerly windloading. Finally, a big thank you to Niwa and Meridian for giving access to their remote weather stations. The data has provided useful insight into the effects of storms on different ranges in the Mt Cook area and has been especially valuable during the long periods this winter when bad weather has prevented direct observations in the backcountry.

At the time of writing we are 10 days into the howling westerly epoch that began on the 16th. Over 3m of snow has fallen at the head of the Tasman so far and it looks like the sunscreen will stay in the tube for a while yet. Despite this the future looks good for spring touring in the region, great snow cover to low elevations, well bridged crevasses, and a snowpack that should settle down reasonably well to the usual spring freeze thaw pattern if ever these westerlies run out of steam.

BY TREV STREAT

AVALANCHE INVOLVEMENTS THIS WINTER: On the 3rd August a guide took a ride of about 100m on a raft of slab when a stiff pocket of ridgeline windslab pulled out while traversing to lower angled terrain on the

+WANAKA REGION+ OVERVIEW All things considered, the 2010 winter was pretty uneventful in the Wanaka region.

Limited amounts of snow arrived at least, during the early and middle pasts of the season and significant storm activity was reasonably unusual. Periods of High danger were infrequent and brief. Most important was the fact that there were no reports of backcountry incidents involving full burial or serious injury – a very pleasing outcome.

WEATHER The 2010 season in the Wanaka region was characterised by long periods with little or no precipitation and generally light winds.

This pattern persisted through until the end of August, when it could be said that winter finally arrived.

MAY The weather in May produced few surprises.

Temperatures were mild, reaching between 6 and 8 degrees during the day on a regular basis and seldom falling below minus 1 at night. Winds were light from the North or West early in the month while a South East flow again, with light winds, developed in the final week of May. This South East flow produced a small quantity of snow (10cm over three days right at the end of the month – 1250m). A layer of inversion cloud hovering between 800 and 1000m was present on most days.

JUNE A Southerly flow prevailed during the first week of June with light South or South West winds and no precipitation to speak of. On the 8th of June 30cm of snow was recorded at 1250m but winds remained light and predominately from the Southerly quarter, The 19th of June was marked by the arrival of a warm, moisture laden North West system that produced a significant quantity

of rainfall (50-60mm plus, in the East of the region) to at least 2000m. A substantial rain crust formed as a result of this event and, it was to become a problem for some time.

The last week of June saw a return to cold, clear conditions and light winds mainly from the South East. This, in turn, lead to the widespread formation of surface hoar, mid pack faceting and the growth of depth hoar at ground in many places.

JULY In early July, we witnessed a long spell of settled weather with virtually no precipitation and light winds principally from the Southerly quarter. These conditions, when combined with the shallow snow pack produced rampant faceting and further depth hoar development in many areas. This situation persisted until July 20th when a weak NW storm delivered a small amount of new snow (10-20cm at 1250m). Small snowfalls continued during the last week of July as the result of weather systems from the Southerly quarter. Winds remained light.

AUGUST The first week of August produced very small amounts of precipitation and light winds from the Northerly quarter. On August 8th, a South East flow delivered 15-20cm of snow (1250m), which was accompanied by light winds. Mid August saw a return to largely settled weather with very limited amounts of precipitation and light variable winds.

The snow pack remained in essentially early season condition during this period, that is to say, shallow and weak in most places.

Large settlements and mainly small remote releases were commonplace. However, widespread, large-scale natural activity was rare due mainly to the fact that new snow loading was insufficient in volume and weight to trigger on the buried weaknesses. Towards the end of August a disturbed Westerly flow

began to assert itself with increased amounts of precipitation and more frequent bouts of strong wind.

SEPTEMBER In early September, it became apparent that winter had finally arrived with a pronounced increase in both precipitation and wind. On the 17th, 30cm of snow fell at 1750m as the result of a North West storm. This pattern continued over the next couple of weeks with frequent snowfalls and gale to severe gale winds from the Westerly quarter. This unsettled Westerly pattern looks likely to continue into October.

AVALANCHE OCCURRENCES AND INVOLVEMENTS Fortunately, backcountry avalanches involving humans were quite rare this season.

There were several reports of human triggered remote releases which must be classified as near misses but according to the records, no backcountry users were fully buried or seriously injured. The rain crust which formed June 19th and subsequently facetted, constituted the principle weakness in the pack during the first half of the season. In mid to late August, the cold, clear conditions produced widespread areas of surface hoar which then became buried. Numerous size 1 and 2 slides, accidental and remote, were recorded in the latter part of August and these were believed to have failed on buried surface hoar. No direct involvements (burials or partial burials) were reported during this period. Large settlements were reported throughout the winter but this is not surprising given the shallow, weak nature of the pack during much of the season.

SPRING TOURING As spring takes hold, it is easy to become somewhat complacent about the potential for avalanche danger. Spring is renowned

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as a great time to go touring but also for unpredictable, turbulent weather. Winter type storms producing slab avalanche conditions are possible at any time. If in doubt, let the snow settle out for a day or so and then select appropriate terrain. With the increasing temperatures and high solar radiation, be wary of crossing sun-affected slopes, which could release unexpectedly as very large (climax) wet slides. Take careful note of warning signs that indicate that slopes are warming and potentially becoming less stable. These can include very soft deep snow; glide cracks and rapidly increasing temperatures. Stay away from terrain traps such as steep, narrow gullies, confined drainages and run out zones, should you feel that things are deteriorating.

Thankyou to the information providers Without the support of local heli-ski companies, guiding operations, ski patrols and keen backcountry skiers and riders and their willingness to exchange information and observations, it would be extremely difficult to compile timely and useful reports.

Thanks are due to all these people for their invaluable information during the winter.

BY SIMON HOWELLS

+QUEENSTOWN REGION+ OVERVIEW It is typical to draw analogies between seasons and it is bizarre how similar to the ‘09 season this season has been, albeit without the fatalities (although there was one we shall discuss later). It was the events of mid season that saw this season take a different path and avoid the major avalanche cycle that the ‘09 season was remembered for. Lets disseminate the season around this region.

WEATHER Early season snowfalls were consistent allowing for early openings of local ski-fields but much like last year, this was followed by an extended period of settled, calm weather, lasting nearly six weeks without any significant snow. When the snow did start arriving it did so in small quantities (10 to 20 CM’s max) again without much wind, this was the main difference between the two seasons. There was a similar period where an Easterly airflow dominated the picture, lots of low cloud and riming of the snowpack. At the start of August there was a significant rain event (also similar to last season), the difference here was with the rain came a rise in temperature. The warm rain followed by a return to colder temperatures and more snow had the snowpack looking strong.

From September a typical spring followed producing great corn snow conditions. To continue the strange paralleling we have had the late return to superb winter snow, making October conditions some of the best of the season.

SNOWPACK The early season dry spell with very cold temperatures weakened the pack, fears of another major avalanche cycle became very real. Then came the familiar pattern of Easterlies with its associated low cloud, cold temps and rimed snow. When the snow began arriving it was in small amounts (less

19 20 CRYSTAL BALL

than 10 CM’s. In fact this region has not received a single snowfall above 20 cms in over 3 years, what has happened to the knee deep falls of the 1990’s, global warming ?) and without much wind. This point is important, the snow was light and unaffected by wind, which we all know is responsible for making slab conditions. Without a slab there was virtually no tension in the snow, this was the single most contributing factor to a decreased avalanche cycle this season. Slowly the snowpack depth grew, eliminating the strong temperature gradient that plagued the early season snowpack.

The early August rain event, complete with warm temps, added a significant amount of free water to the pack. After a week of above average temperatures, winter returned. The pack locked up solid, people could hit some of the steep terrain that had tempted them all season with confidence. Mid winter produced some superb backcountry snow conditions without the fear of large destructive avalanches that we experienced the previous season. The late August early September spring skiing was superb, again consistent with a well consolidated snowpack. This season (as with ‘09) we have experienced a late burst of winter, this late winter snow has been well publicised this year because of its duration and intensity. The initial storm was classified as the largest on the planet at one stage and as many Southland farmers will no doubt recall as one of the deadliest, thousands of young lambs dying throughout the storm. For this region it brought severe gales (some gusts over 160 kph) from the North West, West and South West, snow to around 300m, over 1.5 m of snow in total for over 8 days, some storm cycle.

AVALANCHES There were 9 people caught in avalanches in this region resulting in 4 part/full burials, there are a couple of interesting notes on these burials. Firstly 3 of the burials were backcountry users that had no form of avalanches rescue (no shovels, probes or transceivers!) and all were snowboarders.

The 4th burial (also snowboarder) was the

first known case of an avalanche air bag being deployed in an actual avalanche in NZ, although completely buried the airbag was noticed by a sweep from a helicopter, and a successful and relieved companion rescue was completed. A quick mention about the only fatality reported in this region.

While touring in the Remarkable’s range, a set of antlers (12 pointer) appeared out of avalanche debris, on closer inspection a large red stag was uncovered. It was obvious the animal had perished in a recent avalanche, an interesting event. Has anyone come across something like this before?

CONCLUDING REMARKS Before I conclude, I would like to send out a big thanks to the snow safety crew at the Remarkables, these guys take their work very seriously, the level of reporting, snowpack

and avalanche obs to the info X was, and continues to be, at the highest level of any provider in the country. It has made my job a lot easier, thanks team. I suppose the highlight of the season would have to be the fact we had no fatalities, unfortunately the low would be, this was mainly due to luck. For people to be still heading into the backcountry totally unaware that they are in avalanche terrain, to not carry one piece of rescue equipment, in this day and age is almost unbelievable. Albeit but a twist of fate there could have easily been several fatalities this season. Our work continues, to educate the uninformed, to get the message out there. If you are in a situation were you see people heading backcountry ill prepared then speak up, if you are one of the lucky people to escape this season then educate yourself. The MSC avalanche awareness

campaign is highly visible, the new plans in place will make it even more accessible.

Watch this space as plans are in motion to take avalanche awareness to an all new level next season, see you then.

BY CHRIS COCHRANE

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+AVALANCHE SEARCH DOGS+

While Avalanche Search Dogs have been used in New Zealand for around 20 years, only recently has the national group become part of Land SAR as one of their specialist groups. This structure has allowed Search Dogs, both avalanche and wilderness in New Zealand to become a strong, credible and cohesive group.

WHY USE DOGS?

DEPLOYING AN AVALANCHE SEARCH DOG:

Sense of Smell – dogs have 220 million scent receptors

Search dog mobilisation should be directed through the New Zealand

(we have 5 million)

Police, either local or by the 111 system - if however the dogs and

Speed – they are FAST.

handlers are deployed by other means, then the NZ Police should be

Survival statistics tell us that 90% of avalanche victims are alive at the

notified as soon as possible thereafter.

fifteen minute mark. After 35 minutes the survival rate is at 30% and quickly drops after that. A well trained avalanche dog is equivalent to

It is essential to speed the arrival of search dogs at the accident site

approximately 20-foot searchers and can search the same area in an

and air transport must be a priority for the dogs and handlers. If at

eighth of the time. One dog can search one hectare in approximately

all possible a dog and handler team should be included in the first

30 minutes - it takes 20 foot searchers 4 hours to search the same

response party as this is the best chance of survival for a victim who

area with probes (covering about 2.5% of the total area that the dog

is not wearing a transceiver.When dogs are to be used at an incident

could cover).

site it should be attempted to locate landing and equipment sites downwind from the areas to be searched, this will prevent unwanted

There are currently 14 operational teams in New Zealand. All teams

odours drifting across the search areas. Some dogs are trained to

are assessed annually by Land SAR Civilian Assessors and the NZ

search in pairs and amongst personnel already on the debris site, but

Police Dog Section. This support gives us credibility with the police

you should be aware that a dog handler may require that personnel

as well as an unbiased and professional viewpoint. All dogs must be

leave the debris field or that equipment sites need to be shifted to

deemed to be at an operational level to be accepted on the national

allow the dog the best chance of a swift find.

assessment course and it generally takes a minimum of 2 years to train a dog to that level. Our standards are high – dogs are required

DOGS MUST BE SUMMONED EARLY, DOGS SHOULD BE CALLED

to find 2 human and one article find in a 100m x 100m site in under

WHILE THERE IS STILL A CHANCE OF FINDING THE VICTIM OR

20 mins. In addition, there are minimum skill criteria required for our

VICTIMS ALIVE - NOT AFTER ALL ELSE HAS FAILED!

handlers although of our 14 teams, 9 handlers are highly skilled in

When search dogs are deployed, ensure that further operational

snow safety and hold senior positions as patrollers and guides.

dogs and their handlers are put in a state of readiness in case further resources are required. Don’t forget, dogs can work equally well in the

A list of current operational dogs can be found on our official website

dark.

www.searchdogs.co.nz and is updated after every assessment.

It is important that you know the operational dogs in your area so take

BY KARYN HEALD ROBERTSON

the time to check out the site. Land SAR Avalanche Search Dogs are

NATIONAL AVALANCHE COORDINATOR

the only officially recognised resource.

LAND SAR SEARCH DOGS

22

19 24 CRYSTAL BALL

20

+EARTHQUAKES AND AVALANCHES+

I’LL HAVE MINE SHAKEN NOT LOADED: EARTHQUAKE INDUCED AVALANCHING IN CANTERBURY, NEW ZEALAND A magnitude 7.1 earthquake occurred at 4:35 am (New Zealand Time) on 4 September 2010. With an epicentre just 40 km west of Christchurch city (43.55°S, 172.18°E) and a focal depth of only 10km (Figure 1), the earthquake was widely felt through the entire South Island and the lower half of the North Island of New Zealand. Within the Canterbury region shaking intensities of 6 to 7 were widely felt, with a maximum shaking intensity 9 on the New Zealand Modified Mercalli Intensity Scale (Figure 2). This earthquake is the most damaging earthquake in New Zealand since the 1931 Hawke’s Bay earthquake, but there was fortunately no loss of life despite the == While much of the urban areas in Canterbury suffered damage to buildings, liquefaction, broken water and sewerage mains and disruption to power supplies, it is the impact on the alpine areas and the snowpack in particular that the remainder of this article will consider. It has long been known that avalanches can be induced by large seismic triggers with the May 1970 M7.8 in Peru and the March 1964 M9.2 in Alaska just a couple of the more notable events (See Podolskiy et al., 2010 for a good review). With Canterbury in the middle of the Southern Hemisphere winter it was therefore not surprising to hear that this M7.1 had caused avalanche activity.

Earthquake location map shows the earthquake’s location (star) and the surrounding region (Source: GeoNet, 2010)

EARTHQUAKE DATA The earthquake was widely felt through the entire South Island and the lower half of the North Island of New Zealand with maximum felt intensities of MM9. The observed shaking intensity was documented using the Modified Mercalli (MM) scale. This is a scale used in New Zealand and has a twelve step ranking (opposed to 10), with 1 representing the weakest of shaking through to 12 representing almost

21 25 26 CRYSTAL BALL

complete destruction.

Figure 3: Earthquake damage in central Christchurch (Source: C. Cross, 2010).

The motion of the ground was also recorded by a series of instruments that document the movement in terms of ground displacement, velocity and acceleration. These instruments are located throughout Canterbury (Figure 1), but we will look at the sites nearest the main alpine regions namely; Arthur’s Pass, Castle Hill Village (inland from Springfield), Oxford and finally Christchurch.

The Peak Ground Acceleration (PGA) which was measured at each of the recoding stations, is measured in units of percent-g (%g), where g is the acceleration due to the force of gravity (i.e. 9.8 m/ s2). Values of 8%g to almost 30%g were recorded at Arthurs Pass to Christchurch (Table 1). In studies of building damage a PGA value of 20%g is often used to define the lower damage limit, but recent work also shows substantial damage can occur to buildings at lower PGA values of 10-20%g (e.g. Lee et al., 2003).The pattern of PGA can be quite complicated at smaller scales, showing variability over a few kilometres. This can be mostly explained by the differing soil types and topography near the stations that can significantly change the characteristics of the seismic waves. This small scale variability will influence how PGA is experienced in the mountains.

Figure 2: Isoseismal map shows contours, derived from a model, of equal MM shaking intensity for the earthquake (Source: GeoNet, 2010).

The Peak Ground Velocity (PGV) was also measured at each of the recoding stations, measured in units of centimetres per second (cm/s).

22 26

Values of about 4cm/s to over 30cm/s were recorded at Arthurs Pass

THE EARTHQUAKE WAS WIDELY FELT THROUGH THE ENTIRE SOUTH ISLAND AND THE LOWER HALF OF THE NORTH ISLAND OF NEW ZEALAND WITH MAXIMUM FELT INTENSITIES OF MM9.

to Christchurch (Table 1). In studies of building damage there is a strong relation with increasing PGV, with considerable damage when the PGV exceeds 30cm/s (Lee et al., 2003). Both PGA and PGV give a good correlation with reported shaking for earthquakes larger than magnitude 5 and above (GeoNet., 2010).

TABLE 1: EARTHQUAKE RECORDERS (SEE FIGURE 1 FOR LOCATIONS) (SOURCE: GEONET, 2010).

SHAKING INSTRUMENTS LOCATION

MM PGA

PGV

METHVEN

4-7

-

-

ARTHURS PASS

4

7.98%

4.08 CM/S

CASTLE H=ILL VILLAGE

5

11.44%

10.52 CM/S

LAKE COLERIDGE

5-6

-

-

OXFORD

4-7

15.47%

9.88 CM/S

CHRISTCHURCH

4-8

29.70%

14.82 CM/S*

27.76%

32.13 CM/S#

*Christchurch Aero Club #Papanui High School (both locations within Christchurch)

SNOW STABILITY PRIOR TO THE EARTHQUAKE:

region a cycle of natural avalanche activity was anticipated The forecasters had noted a surface hoar layer that might have been buried

In New Zealand the Mountain Safety Council (MSC) are responsible for

intact on certain aspects, but the main concern was the new snow

daily public avalanche advisories for the key alpine regions (see: www.

and the wind loading, and only the deeper buried layers on particular

avalanche.net.nz). The two main regions impacted by this earthquake

aspects. Explosive control and ski cutting in the Craigieburn Range on

were the Craigieburn Range and Mt Hutt / Arrowsmiths Region. The

the 3rd had generally resulted in very limited activity on eastern half

forecasts for these are produced by assimilating data from a number

slopes. Reported snow stability tests included a CTM14 RP down 5cm

of contributors and sources. The Back Country Avalanche Advisory

within low density storm snow. The buried facets and surface hour

(BAA) on the 3rd of September for the Craigieburn Range and for Mt

(where present) had not been reported to show any sign of activity but

Hutt/Arrowsmiths region were reporting a considerable danger rating,

was still of some concern.

according to the 5 step avalanche danger scale.

Despite this new snow and strong wind loading, snowpack stability In the Craigieburn Range the forecaster noted that the snow is strong

assessments in these regions at elevations from 1500 to 2000m had

at depth on the northern half but remains weak on slopes facing SW-

generally improved from fair-to-poor on the 2nd, to good-to-fair on

E with a host of persistent type weaknesses (surface hoar, facets)

the 3rd. This was mainly because the bonding of the new storm snow

having been buried by the past weeks accumulations (50cm or so with

was considered to be relatively strong and the slabs had been mostly

thicker wind deposits). They noted that the slopes with the persistent

unresponsive in testing. The weaknesses deeper in the snowpack,

weak layer (SW-E) “…remain tender in areas and lack only a trigger.”

such as the lower faceted layer, the crust, and the buried surface

(MSC, 2010).

hoar were still a concern on a few aspects. While this layer had been unresponsive so far, the forecasters knew that the surface hoar layer

27

In general, in the days preceding the 4th of September, both of these

(where buried) and faceted layer were both 5 out of 5 scores on the

regions were experiencing new snow and strong westerly winds.

lemon count for snow structure factors (McCammon and Schweizer,

Reports of slab development on easterly facing slopes above 1600m of

2002). A snowprofile taken on the 30th of August (four days before

around 50 -100cm were not uncommon. In the Mt Hutt / Arrowsmiths

the earthquake) shows the facets, crust and surface hoar, but the new

28 CRYSTAL BALL

(and subsequent) wind loading is noted as the primary concern (Figure

had grown out of a hard crust and was considered to be quite resilient.

4). Further additional new snow load was added to this snow pack in

The southern and southeastern aspects were the locations where the

the subsequent four days.

surface hoar was not destroyed by wind or solar radiation and was believed to be buried intact. In the Palmer Range it was estimated that around 95% of the avalanches observed were on the south and southeastern aspects (Boekholt pers comm., 2010).

Figure 4: Snowprofile in A Basin at Mt Cheeseman Skifield, Craigieburn Range (Source: D. Jackson, 2010).

Figure 5: Avalanches on a south east aspect in the Palmer Range (Source: L. Adams, Methven HeliSki, 2010).

By the end of the 3rd of September most locations were reporting the arrival of another westerly system, with new snowfall and strong

In the Craigieburn Range multiple slab avalanches from size D2

winds from the North West to West. In the Mt Hutt region soft

to D3 released on slopes above 1800m. These were all reported on

slab development with at least 40cm HST on sheltered slopes was

southern and southeastern aspects and were thought to have either

reported by late afternoon of the 3rd. Data from a remote climate

slid on the buried surface hoar layer (100824) or in the facets and

station in the Mt Hutt / Arrowsmiths region indicated that snow and

rain crust layer of 18th August (100818). They were generally over

wind continued throughout the night and that a substantial amount

1m deep and 200 to 500m wide (Figure 6). Numerous similar “Ne”

of new snow and loading would have occurred on the slopes lee to the

(Natural trigger, Earthquake) occurrences were also observed across

western half. The lee slopes (South to East) were now primed and only

the wider Craigieburn, Torlesse, Grey and Black Ranges (Jackson pers

lacked a trigger.

comm., 2010). In terms of overall scale, the maximum distance from the epicentre to a confirmed avalanche caused by the earthquake was

AVALANCHES REPORTED:

approximately 100 km, but unreported avalanche events might have occurred further away.

In the Mount Hutt / Arrowsmiths region multiple slab avalanches from size D1 to D3 released on slopes above 1500m. These avalanches were mainly reported on slopes of the eastern half, but were reported to have occurred on all almost all aspects. The avalanches in the Mt Hutt region had particularly wide and jagged fractures, with one observing noting that they had propagated “differently” to that which was expected for these start zones.

Methven Heliski reported that they “observed a significant natural cycle in the Palmer Range that was caused by the earthquake. Most slides were in the 2000-1800m [elevation] range, mostly size 2, and all on S/SE aspects. [The] Weak layers were the facet and surface hoar combination buried by 40cm HST on 3008 [30th August] and drifted to 140cm crown thickness in some areas. [We] Observed no natural activity on solar aspects. [We] Skied adjacent to slide paths and found good stability thanks to earthquake” (Figure 5).

The surface hoar was thought to be the main sliding layer and this

Figure 6: Looking south west along the Craigieburn Range to Mt Cheeseman, with an example of one of the earthquake induced slab avalanche (size D3, SE Aspect, 1910m) shown in the middle ground (Source: D. Jackson, 2010)

28

In addition to the reported avalanche events, large cracks to the full

the cracks were initially observed on slopes with an angle of greater

depth of the snowpack were observed in the Mt Hutt range. These

than 30 degrees, they are now appearing on much flatter terrain

cracks had the general appearance of glide cracks and extended over

(Figure 7). The Mt Hutt Ski patrol has suggested that they may have

30 meters on south-west and southerly faces. These cracks were

been caused when the shingle bed surface was pulled away from the

generally in the 1800-2000m elevation range but were also observed

snowpack during the earthquake and the unsupported snowpack is

at lower altitudes. Similar cracks were noted at Mt Dobson ski area,

now slumping and cracking. We think that it is likely that these full

approximately 100km away. Unfortunately, new snow covered these

depth cracks are not isolated to just this area. However, neighbouring

cracks shortly after the earthquake and monitoring of them was not

ski areas (such as those in the Craigieburn Range) have now closed for

possible. Now with the spring melt these cracks have re-emerged and

the season and no other reports of large cracks like these have been

the Mt Hutt ski patrol are watching them with great interest. While

received.

Figure 7: Looking south from the top of Mt Hutt Skifield, with an example of one of the earthquake induced full depth cracks shown in the foreground (A) and up close (B). (Source: R. Mguire, 2010)

DISCUSSION & CONCLUSIONS The earthquake triggered widespread avalanche activity throughout both regions, with reported events ranging in size from D1 to D3. The avalanches were predominantly on south and southeastern aspects, but did occur elsewhere as well. Based on very limited observations, the consensus seems to suggest that the avalanches primarily occurred in the layer of buried surface hoar. The south and southeasterly aspects likely had the most developed facets and surface hoar due to their generally more shady exposure. They were also lee slopes during the prior storms and definitely experienced substantial new snow loading. Interestingly, western and northern slopes only saw isolated events and we think that this is likely due to the general absence of the surface hoar layer on these aspects. Additional to the avalanche activity, full depth cracks have also been observed in the Mt Hutt Range and these are likely to be present elsewhere. These cracks may end up behaving like glide cracks as we progress into Spring, but given that no one has experienced them in these locations before (unlike a glide crack with a “normal� location), they do remain a concern.

The modeled and reported forces exerted by the earthquake (as

29

30 CRYSTAL BALL

measured by the MM scale) were less over the alpine regions than

Cross, C., 2010. Christchurch earthquake’s destruction. NZ Herald

those felt in Christchurch. Despite this, the peak ground acceleration

Online.

(PGA) instruments still recorded values of between 8 and 15% gravity

http://www.nzherald.co.nz/nz/news/image.cfm?c_id=1&gal_

(at Arthur’s Pass and Oxford respectively), meaning that a horizontal

objectid=10671049&gallery_id=113677#7073400

force of about 0.08 to 0.15 times the normal load due to gravity was

September, 2010].

[Accessed

4

exerted on the snowpack. This shaking was clearly enough to cause substantial avalanche activity on aspects where the right mix of layers

GeoNet., 2010. The New Zealand GeoNet project. http://www.geonet.

and loading was present. Given the nature of the weakness and the

org.nz/ [Accessed 17 September, 2010].

additional wind loading, these aspects may have avalanched anyway with further loading, but it seems very likely that the shaking from

Jackson, D., 2010. Snow Safety Officer Mt Cheeseman & Mountain

the earthquake triggered these avalanche events. This may be one of

Safety

the first recorded events where we can identify the role of grain type

(Craigieburn Range). Personal communications, 23 September, 2010.

Council

Regional

Backcountry

Avalanche

Forecaster

on earthquake induced avalanche activity, but further work will be needed to provide any further insight on this matter.

McCammon, I., and Schweizer, J., 2002. A field method for identifying structural weaknesses in the snowpack, paper presented at

We were very fortunate that the earthquake occurred at 0430 in the

Proceedings ISSW 2002. International Snow Science Workshop,

morning and not at 1100 on a busy Saturday, as some of these slopes

Penticton BC, Canada, 29 September-4 October 2002.

may not have seen active control and could have caught us unaware.

Mguire, R., 2010. Mt Hutt Ski Patrol. Personal communications, 12 ACKNOWLEDGMENTS:

October, 2010

We acknowledge the New Zealand GeoNet project and its sponsors

Mountain Safety Council (MSC), 2010. Avalanche.net (www.avalanche.

EQC, GNS Science and LINZ, for providing data and images used in

net.nz).

this study. We also acknowledge the ongoing snow, weather and

Podolskiy, E.A. Nishimura, K., Abe, O., Chernous, P.A., 2010.

avalanche observations from all of the contributors to the New

Earthquake-induced snow avalanches: I. Historical case studies.

Zealand Mountain Safety Council Avalanche.net, but in particular;

Journal of Glaciology, Volume 56, Number 197, 431-446 (http://www.

the lead forecasters for the two regions (Kevin Boekholt and Damian

igsoc.org/journal/56/197/j09j125.pdf)

Jackson), Mt Hutt skifield, Methven Heliski, Porters skifield, Mt Cheeseman skifield, Broken River skifield and Craigieburn Valley

William H. K. Lee, William Hung Kan Lee, International Association

skifield.

of Seismology and Physics of the Earth’s Interior, Committee on Education, Hiroo Kanamori, Paul Jennings, International Association

BY JORDY HENDRIKX, ANDREW HOBMAN, KARL BIRKELAND

for Earthquake Engineering, 2003. International handbook of earthquake and engineering seismology, Part 2, Academic Press, 1945pp.

References Boekholt K., 2010. Mountain Safety Council Regional Avalanche Forecaster (Mt Hutt / Arrowsmiths), IFMGA Guide, Director of Methven Heliski & Alpine Guides. Personal communications, 22 September, 2010.

•

Helps prevent full burial in the event of an avalanche

•

Has been shown to decrease mortality rate to 3-4%*

•

Head On Top technology (H.O.T) helps keep your head up and your body upright in the avalanche

•

H.O.T. also increases trauma protection for the head, neck and chest

•

15 litre, 30 litre and 45 litre versions

Available in New Zealand direct from SNOWPULSE NZ For more information - www.snowpulse.ch - snowpulsenz@gmail.com - 021 909 315

* Ref: Brugger/Faulk, Analysis of avalanche safety equipment for backcountry skiers.

30

For many people the jury is still out on the helmet issue. US studies that have suggested that helmets decrease head injury in skiing and boarding by 60% plus. But statistics from North America include incidents that involve trees. These need to be adjusted for any application to the NZ situation.

The pathologist observed that a the use of a helmet would not have influenced the cause of death in any of the cases from last year and in at least one of the most recent fatal accidents, off the back of Mt Hutt, a helmet was worn. North American stats also show an increase in neck injuries in kids wearing helmets.

Finally there is the “perceived safety” mentality (10 foot tall and bulletproof) when people slip on a helmet.

All this aside, helmets certainly reduce the potential impact pressures to the head. The Mountain Safety Council’s stance is “a strong recommendation for the use of helmets by the public” but we do not necessarily support legislation.

31

32 CRYSTAL BALL

IN THE FOLLOWING ARTICLE, MICHAEL LAMONT, NZ SKIFIELD INJURY RESEARCHER AND HON MEMBER OF THE INTERNATIONAL SOCIETY FOR SKIING SAFETY GIVES HIS PERSONAL PERSPECTIVE ON THE ISSUE.

+THE HELMET DEBATE+ Should ski-field users (skiers and snowboarders) wear a protective

University students by some simple psychometric testing – getting

helmet? The clear answer is YES – absolutely! Why and what’s the

the students to do some simple writing and some simple arithmetic

evidence?

deduction while oxygen was slowly withdrawn from the air – as if gaining altitude. Those with very minor (and otherwise not noticed)

Firstly the ‘why’ question. To best understand that it is necessary to

performed significantly worse than those who had not had any

understand some mechanics and some New Zealand injury statistics.

‘concussion’. In contact sports (rugby, league, boxing, wrestling and

The brain is a soft and malleable structure which sits inside the

gridiron) the rule of thumb is that if a player has had a bang to the

skull and is surrounded by tissues that ‘hold’ it in shape. The skull

head that has caused any loss of cerebral/motor function then they

itself is strong although its strength is not uniform - in some places

must not play again for a month. Two episodes in a season and no

it is thicker than other places. And of course the brain is the ‘nerve

playing for a year; three episodes then no playing for life. It is very

centre’ of our existence. Damage the nerve centre and we lose some

clear in boxing to see the repeated damage to the brain – referred to as

function - from small losses to very large losses. There are two forces

being “punch drunk”. In the USA some research is being undertaken

that cause brain trauma – the movement of the brain within the

using accelerometers in the helmet of gridiron players to determine

skull and direct injuries to the skull (penetrating fractures or general

the upper limit of potentially damaging forces so that players can be

fractures which tear the inner lining tissues). The movement of

pulled from the field when they reach a critical accumulative level.

the brain within the skull is caused by deceleration forces – falling backwards and hitting your head on concrete/ice. The brain is

It is beyond belief that skifield users will be exempt brain trauma

damaged in 2 places – at point of contact and at the opposite side as

when falling or stopping suddenly against an obstacle such as a rock.

the brain pulls away from the supporting tissues as it moves towards

Will a helmet prevent such trauma? Without a shadow of doubt. A

the point of contact in a deceleration mode.

helmet will reduce penetrating injuries to the skull and will reduce

Snow sports are about gaining potential energy (riding up a lift) and

the deceleration forces associated with sudden stops. The helmet will

expending that energy on the way down. The object is of course,

not reduce all deceleration forces particularly if there is high speed fall

to control that energy expenditure – if it is uncontrolled an injury

but it will reduce some. All ski racers must wear a helmet; all motor

is likely. Head trauma is either the first or second most common

car and motor bike racers wear a helmet and there is a lot of evidence

injury on the NZ skifield. Many of the injuries are lacerations

that they do well in high speed crashes. A helmet will not stop deaths

however concussion (with or without loss of consciousness) is major

due to other trauma – spine fractures or liver or other organ ruptures.

contributor to brain injuries. The cost of a death in NZ is about $2.2m as calculated by the NZ Road Transport Authority. The 3 deaths at

SHOULD YOU WEAR A HELMET? OF COURSE – IF YOU VALUE

Mt Hutt have cost the NZ economy $6.6m – apart from the social

YOUR HEAD!

loss. In the USA 1.5m people suffer from a mild traumatic brain injury without any loss of consciousness and an equal number suffer

I have picked up a number of people who would be alive today if they

trauma with loss of consciousness. Some world leading research was

had been wearing a helmet (penetrating injuries; ‘egg shell’

undertaken in NZ by the late Dr D Gronwell at Auckland Hospital.

fracture; severing of part of the cerebellum during deceleration).

She was able to accurately detect brain damage in a large group of

For more information on helmets visit www.skihelmets.org

32

+OUTCOMES MODEL+ WHERE ARE WE GOING AND HOW WOULD WE KNOW IF WE ARE GETTING THERE? WHERE ARE WE GOING? Traditionally organisations have been able to describe their outputs, for example, the number of manuals produced, avalanche course held etc. However, increasingly the challenge for any organisation is to be

WE WILL LITERALLY BE ABLE TO PROJECT EACH OF THE ORGANISATIONS VISUAL OUTCOMES MODELS ONTO THE WALL AND SEE WHAT WE ARE DOING AND IDEALLY IDENTIFY WHAT WE COULD BE WORKING ON TOGETHER AND HOW WE CAN WORK SMARTER.

clear about what outcomes they are setting out to achieve and what processes and measures they can put in place to know if they are achieving their stated outcomes.

HOW WOULD WE KNOW IF WE GET THERE?

In 2010 MSC has been working hard to develop its outcomes model

Having mapped our outcomes, MSC have then identified some

which visually and clearly portrays what it is we are working towards

evaluation questions and indicators which would enable us to better

and then maps evaluation questions and indicators onto this model.

understand how well we are achieving our outcomes. This is an

The entire model has a necessary degree of complexity, however the

ongoing process but includes external expert review, stakeholder

diagram below provides an overview of the high level outcomes that

surveys and internal data gathering processes.

MSC is working towards. To read this model, start with the ultimate

also been prioritised by the MSC executive which then drives our

outcome “people participating more safely in land based outdoor

business plan. Thus, any new projects need to clearly identify what

activity” and then the steps to the left indicate the outcomes that

outcomes it is contributing towards. The visual software also enables

need to occur to achieve this.

us to track and link projects to outcomes. Thus, any new avalanche

The outcomes have

projects need to be clearly shown to assist the organisation to achieve its outcomes.

WHAT DOES THIS MEAN FOR THE AVALANCHE COMMUNITY? MSC and the Avalanche programme will have identified and prioritised outcomes and all avalanche projects will be clearly targeted to achieving these outcomes. In working with MSC the avalanche community can be confident that we are focused and working hard to both achieve our outcomes but also be able to know that we have achieved them i.e.

MSC knows where it is going and will know when we get there! There is a great level of detail around the MSC model and outcomes models in general.

Much more detailed information, and a case study of

Page 1

In addition to MSC going through this process we have also shared the

MSC process can be found at Duignan, P. (2010). How a not-for-profit

skills, process and tools with a number of other outdoor and Council

community organization can transition to being outcomes-focused

organisations. What this means is that in the future many of us and

and results-based - A case study. Outcomes Theory Knowledge

potentially all of us will all be using the same language and the same

Base Article No. 278. (http://knol.google.com/k/paul-duignan-phd/

tools to articulate our outcomes. The organisations currently involved

how-a-not-for-profit-community/2m7zd68aaz774/156 I am happy

in this process include, NZ Alpine Club, Outdoors New Zealand, NZ

to answer any questions or receive any comments regarding MSC

Recreation Assoc, Education Outdoors NZ and Hillary Awards. SPARC

outcomes model and look forward to engaging with you to achieve

have also been very interested in our outcomes model process and

the outcomes now and in the future.

have attended our multi organisation working group meetings. The Department of Conservation have also recently gone through the

ANNIE DIGNAN

same process and developed an extensive visual outcomes model.

Programme Manager Research and Evaluation

What this means for the future is that:

New Zealand Mountain Safety Council.

33 34 CRYSTAL BALL

CONTROL WORK AT DAWN TUOA SKI FEILD

34

apply in ok Natio n

al Park? in is serio

us errain an d a mod era e majorit y of the p te amount ark is co mands re mple spect fro m all who x ider care fully the cl ass of oing into , and che ck the rior to un dertaking any trip.

avalanch e terrain, uld only go up or e danger is low. d to be evel rises while

cook n ational

park

Park

mount

nt Cook

National

The Back Avalanch country e Adviso ry is provid ed by the Mountain Safety Council, and is available at www.ava lanche.n et.nz

Road, Ao raki/Mou

rough co mplex to avoid being his route wh ones to p en rod ntre to se uce e if

BA Backcou A – ntr Avalanc y he Advisory

aoraki/

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Ball Hut

ss the ro ad each winter not stop in any of the k with the visitor ce ntre on prior to walking o r

Avalanc

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nche on

people a t the outle t end d. You sh ould not go ake unle ss you h ave the

ATES and the BAA should be and man used toge aging pe rsonal ris ther for ev k in the ba aluating There are hazards ckcountry inherent ris . ks routes de in backco scribed he untry trave re avalanch l, and mos will at tim es. The D es be un t of the epartmen safe due provide ac to potent t of Conse curate in ial snow rv at fo io rm n has do typical of ation desc ne each gene its best to ribing the ral region However terrain ch , based on , it is up to aracteris tics its current you to us risk-man e this info knowledg agement rmation to e. decision backcoun s and lear make yo try travel, ur own n the nece to access and to ex ssary skill additiona ercise ca s for safe l trip-plan ution whi informatio ning mat le travelli n is no su erials, ng in back bstitute fo country ar r experie eas. This nce and good judg ement.

be avalan ch

Published by Departm ent of Co nservatio Canterbu n ry Conser vancy Private Ba g 4715 Christchu rch, New Zealand 2010

oto: Avala

can occu ra n the park t any time of the . Climbers mmer at higher ele can be vations. nches ca n occur o n some road. To reduce ris k, the

Be avala nche aw are!

If you are going into sure you places a : valanche s could o • have ccur, ma checked ke th e ATES cla go and th ss for wh e BAA fo ere you w r the ava • have ant to lanche ra the skills ting for the AT • take E S cl a an avala ss you a n re che transc going into probe. K eiver, a sn now how ow shove to use th l and a ese tools Risk sta ! tement

www.doc

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.govt.nz

AN EXAMPLE OF HOW DOC WILL BE USING/PUBLICIZING ATES

35 36 CRYSTAL BALL

+THE www.avalanche.net RE-DEVELOPMENT+ The Mountain Safety Council’s web site – www.avalanche.net.nz has long been the hub for the communication of avalanche hazard information. After ten years of great service, it is finally time for a makeover. The first premise of risk communication is – know

TAKING A WHOLE COMMUNITY APPROACH TO RISK COMMUNICATION HAS BEEN THE BASIS OF THE NEW WEBSITE DESIGN.

your audience. We have been doing a lot of work on understanding whom we are communicating with and how to engage these groups.

programme going. The programme needs the support of the

Intensive research into out of bounds and backcountry users has

commercial sector through sponsorship and the new website gives

highlighted that multiple levels of approaches are required to

the Mountain Safety Council an opportunity to promote high value

successfully connect with and hold this wide audience. These include

and corporate exposure to perspective sponsors. The programme also

social engagement through Youtube, Twitter, Facebook and regular

needs the financial support of the public who are using the safety

community functions, talks and events. The delivery of education is

information and again the new website allows for direct donations

still a strong focus at all levels as is the preparation of an Avalanche Danger Advisory. The Advisory needs to be delivered in a tiered

and the promotion of fundraising functions and events.

It will greatly increase the ability to relate to all the people that seek

approach with broad regional information first followed by specific

safety information and grow awareness of the avalanche issues that

issues (what, where, when, likelihood and consequence). Finally,

may be encountered while working and playing in New Zealand’s

in-depth information should be available (weather, snowpack and

great outdoors.

avalanche observations).

The Mountain Safety Council hopes to be able to trial the new website

The use of “push techniques” is also very important in the

by late summer and have it ready to go by the winter of 2011. Many of

dissemination of information. This includes pre-recording the

the current users completed the online survey that was attached to

advisory for radio, e-mail, txt updates and links with related websites.

the existing site and we welcome and thank you for your feedback.

Connected to this is the ease of access to the information. Although

Most of the comments about improvements to the website were

our cell phone coverage in New Zealand may not be keeping up with

included in the planning process and we believe the new product will

technology, the website must be accessible for modern phones to

be of a high value to all user groups. Preliminary mock-ups of the

receive forecasts and send current observations and information.

new –www.avalanche.net website. These are concept development

The reality of the current, and future, financial climate is that

images to plan the functionality and usability of the site. We are still

significant external funding is required to keep the Avalanche

working on form and overall look.

+CRYSTAL BALL SUBSCRIPTIONS+ WE NEED YOUR SUPPORT SUBSCRIBE TO THE CRYSTAL BALL FOR 2011!

41 38 CRYSTAL BALL

Snow study kits, Crystal Cards, Digital Thermometers and more.....

Pocket Snow Density Gauges

25, 70* 100cm Folding Snow Saws

+KNOW BEFORE YOU GO+

NEW ZEALAND MOUNTAIN SAFETY COUNCIL

CRYSTAL 2010 BALL AVALANCHE MAGAZINE VOLUME 20

BCA Tracker avalanche transceiver training parks are open and available to all backcountry enthusiasts at five New Zealand resorts. Ask the ski patrol for details at Remarkables, Cardrona, Treble Cone, Porters or Craigieburn.

NZ Distributor – BCA@Sportive.co.nz Ph 03 3489 725 Visit www.mountainsafety.org.nz

40 CRYSTAL BALL