eiscat

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EISCAT_3D The Most Sophisticated Radar ever built

Esa Turunen EISCAT Scientific Association, Kiruna, Sweden

EISCAT_3D Preparatory Phase Kick-Off, Stockholm 21.10.2010



Geospace - a vital part of our environment We live in the neighbourhood of a star, SUN • Key questions: – How does Space Weather affect the climate? – How do the atmospheric layers couple to each other?

Energetic particle precipitation creates NOx and HOx

O3 is affected ! NOx is long-lived in the absence of sunlight


Goal: Comprehensive Earth System Modeling should include whole geospace Modeling climate’s complexity. This image, taken from a larger simulation of 20th century climate, depicts several aspects of Earth’s climate system. Sea surface temperatures and sea ice concentrations are shown by the two color scales. The figure also captures sea level pressure and low-level winds, including warmer air moving north on the eastern side of low-pressure regions and colder air moving south on the western side of the lows. Such simulations, produced by the NCARbased Community Climate System Model, can also depict additional features of the climate system, such as precipitation. Companion software, recently released as the Community Earth System Model, will enable scientists to study the climate system in even greater complexity. ©UCAR


Particle precipitation into the atmosphere: • increased energy input – atmospheric dynamics changes

• increased ionisation – conductivity changes – radio wave propagation changes – chemistry changes

• increased dissociation – chemical effects

• increased excitations – beautiful Northern Lights! – chemical effects


Polar vortex • Normally at 60° N • Isolates the air in the polar area from rest of the atmosphere, 16km - mesosphere.

(from A. Seppälä)


SPE 2003: GOMOS NO2 and O3 (46 km) 1.5x1011

1

0.7

0.7

0

O3 46km

1.5 x 1011

SPE

After the SPE

8 x 108

8x108

1

1

8

NO2 46km

Before the SPE

(from A. Sepp채l채 et al.)

EISCAT 3D User Meeting 28th May 2009

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EISCAT Scientific Association

[km]

HOx

January 2005 SPE: O3 -loss at 70-80 km as high as 80%!

NOx

O3

Calculated HOx and NOx (log10ppbv) and O3 change (%) for the JAN 2005 SPE’s (from A. Seppälä, 2005)


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Growing experimental evidence for significant mesosphere-stratosphere interactions

Above: Meridional lower thermospheric winds by 4 SuperDARN radars and Stratospheric temperature at 2mb 2004-2007. Unpublished data, shown with permission of the author Rob Hibbins, BAS.

Left: Zonal average ACE-FTS NOx in the Northern Hemisphere from 1 Jan through 31 Mar of 2004 – 2009 Randall et al., GRL, vol 36, L18811, doi:10.1029/2009GL039706, 2009


Could these couplings change the surface temperatures?

Rozanov et al., 2005

Sepp채l채 et al., 2009

40 years of surface T data show consistent areas with +4 C warmer during magnetically active winter months (right). General Circulation Model study with Energetic Particle Precipitation shows similar consistent structures as experimental data on Earth surface temperatures during high solar activity, in Sepp채l채, A., C. E. Randall, M. A. Clilverd, E. Rozanov, and C. J. Rodger (2009), Geomagnetic activity and polar surface air winter months temperature variability. J. Geophys. Res., 114, A10312, doi:10.1029/2008JA014029


Another side of the coin: Effects of greenhouse gases o global warming in the troposphere o cooling in the middle atmosphere various layers in the ionosphere (e.g. aurora) decided by pressure levels

ionosphere – occurring progressively lower down 90km

upper atmosphere (”mesosphere”): contraction

’fridge effect - cooling

15km

greenhouse effect - warming time Courtesy of Chris Hall, UiT

lower atmosphere: expansion


warming at 10hPa level on January 24 – 25, 2008. (b) Abatement in the zonal mean zonal flow at 60!N. The EISCAT Scientific Association stratospheric warming occurred during (c) low solar flux and (d) quiet geomagnetic conditions.

!18km altitude resolution) modes. [8] Figure 3 (left) shows baseline (i.e., January 2007) ion temperatures at 130 km and 230 km (F-region peak), with error bars representing standard deviation for 1-hour bins. Figure 3 (right) shows the observed difference between January 2008 data and baseline data for 130km and 230km altitudes (dark symbols) as well as the difference expected from the empirical model (light symbols). As the reference case of Jan 20 – 23, 2007 had slightly different

ion temperature data in this study as it provides direct evidence of energy coupling between different layers of the upper atmosphere. In addition, ion temperature is a good measure of neutral temperature for lower heights, and close GONCHARENKO AND ZHANG: IONOSPHERE-STRATOSPHERE COUPLING L21103 toL21103 exospheric temperature at !250 km. Variations in other parameters and latitudinal and longitudinal relationship between ionospheric changes and location of the SSW will eastward wind. This SSW occurred during very low and slowly changing solar activity (F10.7 = 71– 74) and low be investigated in separate papers. geomagnetic activity (Kp < 3+, Ap3 = 0 –22, average Ap3 = 7), thus reducing influence of these major drivers of iono2. January 2008 Sudden Stratospheric Warming spheric variability. [6] Figure 1 summarizes stratospheric and geophysical conditions during the campaign period, January 17, 2008 – 3. Results and Discussion February 1, 2008. After staying at historically low levels in [7] Measurements of ionospheric parameters (Ne, Te, Ti, December 2007 and first part of January 2008, stratospheric temperatures began increasing on January 21 – 22 and wind) were obtained by the Millstone Hill ISR from January reached a peak on January 24, 2008, indicating sudden 17, 2008 to February 1, 2008. We limit this study to daytime stratospheric warming. Figure 1a shows NCEP stratospheric data only to avoid influences from the midlatitude trough, temperatures at 10hPa (!30km) for 90!N (triangles) and which was observed on several nights. To minimize temperzonally averaged temperatures for 55 – 75!N (circles) in atures variations due to solar ionizing flux, geomagnetic January 2008 (solid lines) in comparison with !30-year activity, and season [Zhang and Holt, 2007], we use as a median temperatures (dashed lines). At 90!N, the warming baseline case data from January 20– 23, 2007, with F10.7 = and Kp < 3+ (Ap3 = 3– 8, average Ap3 = 5). Figure 2 exceeded 70K and the peak temperature of 267K broke all- 79 Figure Difference of ion temperature between presents 2.difference fieldfield of daytime ion temperature at time record. The temperature anomaly shows a clear down- mean January 2008 data and mean January 2007 data. A altitudes of 100– 300 km between mean January 2008 data ward progression, with peak warming at 30hPa (!23 km) 20 – 50K decrease in temperature is observed above (i.e., Jan 17– Feb 1 period) and mean January 2007 data occurring 2 – 3 days later (not shown). The stratospheric !140 km in the morning hours (7 – 11LT) and afternoon (i.e., Jan 20 – 23 period). A 20 – 50K decrease in mean circulation, characterized in Figure 1b by a zonal mean January hours (152008 – 19LT). A narrowisarea of warming observed temperature observed aboveis !140 km,in zonal wind at 60!N and 10hPa, shows decrease in the with the lower thermosphere at !120 – 140 km.recorded in the maximum temperature differences

Thermosphere is affected by stratosphere! • stratospheric warming is recently seen to be connected with large temperature variations in thermosphere by the Millstone Hill radar.

morning hours (7 – 11LT) and afternoon hours (15 – 19LT). Figure 1. Stratospheric winter of January 2008 (solid 2 of The 4 lower thermospheric warming in the altitude range of from: Goncharenko al., inGRL, VOL. 35,The lines) in comparison with 30-year mean January conditions !120 – 140 km exceeds 30et – 50K the afternoon. (dashed lines). (a) NCEP zonally averaged stratospheric observed L21103, doi:10.1029/2008GL035684, variation in ion temperature is consistent for all temperatures at 10hPa (!30 km) in different latitude bands. three antenna pointing directions and for of both alternating 2008, “Ionospheric signatures sudden A SSW event occurred in late January 2008, with peak code (i.e., !5km altitude resolution) and single pulse (i.e., stratospheric warming: Ion temperature warming at 10hPa level on January 24– 25, 2008. (b) !18km altitude resolution) modes. at Abatement in the zonal mean zonal flow at 60!N. The Figure 3 latitude” (left) shows baseline (i.e., January 2007) ion [8] middle stratospheric warming occurred during (c) low solar flux temperatures at 130 km and 230 km (F-region peak), with and (d) quiet geomagnetic conditions. error bars representing standard deviation for 1-hour bins. Figure 3 (right) shows the observed difference between January 2008 data and baseline data for 130km and ion temperature data in this study as it provides direct 230km altitudes (dark symbols) as well as the difference evidence of energy coupling between different layers of expected from the empirical model (light symbols). As the


... Photo courtesy of the NAIC - Arecibo Observatory, a facility of the NSF ... Photo by David Parker / Science Photo Library

Arecibo, Puerto Rico

440 MHz 1-2 MW 305 m antenna diameter


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INCOHERENT SCATTER -the most sophisticated radio method to remotely sense the atmosphere and near-Earth space • Parameters measured simultaneously: – – – –

electron density electron temperature ion temperature line-of-sight plasma velocity

Data is available via Madrigal data base -Madrigal is a coordinated VO-type access to global ISR data

The overarching goal in ISR development: More efficient geospace management


height

Electrons scatter the radio wave....

time High-power radio pulse

sensitive receiver


UHF 933MHz

16


UHF-receivers


VHF 224MHz

18


ESR 500MHz Svalbard


EISCAT Scientific Association

Courtesy of Y Ogawa and A Saito, Google Earth

Our view is currently at best 2-dimensional We will turn it to be 3-dimensional Courtesy of Y Ogawa and A Saito, Google Earth

European Incoherent Scatter Scientific Association


EISCAT Scientific Association

EISCAT_3D

• EISCAT_3D is a 3-dimensionally imaging radar • Continuous measurements of the space environment - atmosphere coupling at the statistical southern edges of the polar vortex and the auroral oval.

By: Allain et al., 2008


EISCAT Scientific Association

3D Electron density retrieval from TEC (Total Electron Content) measurements by GPS

The images above are based on mathematical inversion from phase measurements of GPS satellite signals. Results dramatically improve when measured profiles are added to the calculation - or if a true 3D image is measured! By: Allain et al., 2008


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Artist EISCAT_3D Planimpression for future: of EISCAT_3D SCALE: several 10’s of thousands of antennas


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Similarity to modern radio astronomy

•SKA project

•artist image below

•LOFAR (Low Frequency Array)

•in fact one LOFAR international site was ordered to Finland, to be installed as a test and technology prototyping receiver site for EISCAT_3D in Northern Finland.


EISCAT Scientific Association



Radiation belts show high variability of high-energy electrons

• complex behavior during magnetic storms • loss process in the radiation belts: precipitation into the atmosphere


EISCAT Scientific Association

Effects on navigation and space-based radars

Does GALILEO work at high latitudes?


EISCAT Scientific Association

Ionospheric impact on navigation


EISCAT Scientific Association

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Meteor studies, recent example

The Ph.D. thesis “High-resolution meteor exploration with tristatic radar methods” by Kero (2008) describes a method to determine the position of a compact meteor target with the EISCAT UHF system. This figure displays 194 meteoroid trajectories projected onto a plane perpendicular to the Tromsø radar beam. The maximum SNR of each meteor head echo streak is normalized to one. The white circle marks the -3 dB beamwidth (0.6°).


EISCAT Scientific Association

Meteor studies The Ph.D. thesis �Radio meteors above the Arctic Circle - radiants, orbits and estimated magnitudes� by Szasz (2008) describes meteoroid orbit calculations from EISCAT UHF measurements. This figure displays the sun (yellow), the Earth (blue) and 39 prograde (green) and retrograde (red) meteoroid orbits.

With EISCAT 3D we could map the whole dust cloud of the solar system!


EISCAT Scientific Association

The role of smoke particles

Nanometre-sized meteoric smoke particles (MSP) formed from the recondensation of ablated meteoroids in the atmosphere at altitudes >70 kilometres, are transported into the winter polar vortices by the mesospheric meridional circulation and are preferentially deposited in the polar ice caps. Further smoke particles resulting from recondensation of the meteoric vapor, are believed to be an important ingredient in a number of mesospheric processes.


!"#"$!%&"'(!%)*)+,-($%.!,/"+&"!0($1%."/!2/)3! 4,,/%."1%)*5!6)*!)712/)3!(0(*1+ 89+($0(!8:;!<(:;!<:!%)*+ =("$.-!2)$!+%'*"17$(+!)2!2%(/#""/%'*(#!,)1(*1%"/!#$),+


!"#$%!&'#$(!)(*"+&


EISCAT Scientific Association

Recent highlights Space debris detected using the EISCAT UHF system on May 14-15th 2009, a few months after the Iridium-Cosmos satellite collision. The Iridium cloud orbital plane passes are visible at about 00:00 and 13:00 UT; and the Cosmos cloud pass at about 00:00 and 06:00 UT. The figure also compares the measurement with a statistical debris model called PROOF. Differences show that the model could be improved by using the EISCAT measurements. (from J. Vierinen et al., 2009)


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EISCAT Reaching for the Moon EISCAT Reaching for The Moon Credits: Juha Vierinen and Markku Lehtinen, Sodankyla Geophysical Observatory, Finland


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Radar reflectivity map of Moon, made by using EISCAT Reach down to 600 m resolution!


Development of US radars

AMISR Advanced Modular Incoherent Scatter Radar

384 Panels, 12,288 AEUs 3 DAQ Systems 3 Scaffold Support Structures


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Poker Flat Incoherent Scatter data by J. Semeter et al.

Example on volumetric data: PFISR

Semeter et al., JASTP., 2008


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Imaging radar: Jicamarca 50 MHz


EISCAT Scientific Association

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Unique science opportunity in order to answer important fundamental questions: - Energy input from solar wind -> magnetosphere ->ionosphere - Solar variability effects in the atmosphere in the Arctic - Coupling of atmospheric regions - Turbulence in the neutral atmosphere and space plasmas - Dust and aerosols, meteoric input - Ion outflow at high latitudes Note: The wind field can be measured continuously in the whole atmosphere, in a large geographical area, with high resolution, as a 3D image!

EISCAT_3D + EISCAT Svalbard Radar +existing infrastructure (Andoya, Esrange,SIOS, Heating, Radar, Lidar, Riometer, Magnetometer, GPS, Tomography receivers, etc.)

European Window to Geospace in Northern Scandinavian Arctic


Credits: NASA ESA EISCAT Scientific Association SGO Andøya Rocket Range Finnish Amateur Astronomy Society URSA Jyrki Manninen Thomas Ulich Tero Raita Carl-Fredrik Enell Antti Kero Kari Kaila Tony van Eyken Pekka Verronen Annika Seppälä


EISCAT Scientific Association

Atmospheric Energy Budget 

Coupling processes − − − − − −

 

Particle input Chemical coupling Dynamical coupling Ion-neutral coupling Electrodynamics Potential drops, acceleration

Short-term variability Long-term change −

Anthropogenic effects

APPENDIX, EISCAT_3D Science areas


EISCAT Scientific Association

Space Plasmas (1) 

Dusty plasmas − −

Turbulence − −

PMSE Aerosols Neutral turbulence Plasma turbulence

Small-scale processes − − − −

Auroral fine structure NEIALs Thin layers Small-scale dynamics

APPENDIX, EISCAT_3D Science areas


EISCAT Scientific Association

Space Plasmas (2) 

Large-scale processes − − − − −

Auroral forms Magnetospheric dynamics (Convection, storms, substorms) Reconnection Ion outflow

APPENDIX, EISCAT_3D Science areas


EISCAT Scientific Association

Space Environment (1)   

Space Weather Space debris Meteors − −

Planetary Radars −

Orbits Meteoric input Near-Earth Objects

Solar Wind measurements (and coronal radar)

APPENDIX, EISCAT_3D Science areas


EISCAT Scientific Association

Space Environment (2) 

Service applications Navigation − Satellite tracking − Polar Flights −

APPENDIX, EISCAT_3D Science areas


EISCAT Scientific Association

New Techniques (1) 

New experimental philosophies − − − − −

Troposphere/Stratosphere Continuous measurements up to MLT New Coding Strategies Higher Time Resolution Orbital Angular Momentum

Active experiments − − − −

Ionospheric Modulation PMSE modulation Electrojet Modulation Ionospheric Alfven Resonator

APPENDIX, EISCAT_3D Science areas


EISCAT Scientific Association

New Techniques (2) 

Interferometry and imaging − − −

Data processing −

ISR interferometry Tristatic interferometry (meteors) HF interferometry (stimulated emissions) Removal of meteors and space debris

Assimilation and modelling

APPENDIX, EISCAT_3D Science areas


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