We’re buying a TV set tomorrow! And we’re going to watch the weather Forecast every hour!
Mo o?!
I’m going to get the Internet, too! Let me just save Daisy first!!!
Let’s get out of here, rat brothers!
Oh, my! Apocalypse is coming!
Learn and Try Series
Meteorology The first edition Idea by Ljiljana Marinković Written by Nedeljko Todorović • Illustrated by Ivica Stevanović • Graphic design by Dušan Pavlić Reviewed by dr Dijana Plut • Editor of the edition: Milena Trutin • Proofreader: Mirjana Delić Prepared for printing by Ljiljana Pavkov For publisher: Dejan Begović, executive director Published by KREATIVNI CENTAR, 8 Gradištanska street, Beograd contact: +381 11 38 20 483, 38 20 464, 244 06 59 www.kreativnicentar.rs e-mail: info@kreativnicentar.rs n
Printed by Publikum Number of copies 2.000
I can’t believe it’s raining again!
N e d e l j k o To d o r o v i ć
MeTeorOlogy Illustrated by
Ivica Stevanović
Raining frogs or some other animals is a rare natural phenomenon that might occur after a heavy storm.
CONTENTS 5 ... On meteorology 6 ... Reading the Signs of Nature 8 ... Meteorological Measurements and Observations 9 ... Set up the measuring instruments 10... Diary of Measurements and Observations 11 ... Follow the daily changes in temperature 12 ... Learn more about the changes in air pressure 13 ... Follow the changes in air humidity 14 ... Wind 14 ... How to assess wind direction 15 ... How to assess wind speed 16 ... Clouds 17 ... How to recognize different cloud types 18 ... How to follow cloudiness
Don’t worry! It’s just an ordinary lightning - it’s a natural phenomenon… You’ll understand in a couple of millions of years, anyway…
18 ... 19 .. 20... 20... 21 .... 21 .... 22 ... 24 ... 26 ... 26 ... 27 ... 27 ... 28 ... 30 .. 32 ...
Where did the lighting strike? Precipitation How to measure daily rainfall Atmospheric Front Weather Forecast Is it going to rain tomorrow? How to read weather maps and symbols People who contributed to meteorology Advantages of a meterologist’s job Some difficulties How to Become a Meteorologist Where can I work as a meteorologist? If you become a meteorologist, you can find out about... Glossary Index
Just my luck! I can’t believe there’s a storm now?!
Hey! Look out!
ON METEOROLOGY ave you ever been caught outside in the rain while coming
Hhome from school? You had left for school on a lovely sunny morning, but during the last class you noticed that the sky turned cloudy. When school finished, it started raining and you came home soaked to the skin. So you said to yourself: If I had listened to the weather forecast yesterday, this may not have happened. Weather conditions are very important to many people. Builders find it difficult to work in the cold weather. To grow plants farmers need rain; but they need dry weather for the harvest. Sailors and pilots try to avoid storms and mountaineering can be very dangerous in fog and while it thunders. That’s why they carefully follow weather reports and make plans according to them. This book will help you learn about how meteorological measurements are carried out, how different natural phenomena are observed and how the weather is predicted using the obtained results. These will be your first steps in meteorology – the scientific study which focuses on weather processes.
Tornado is common in some countries. It is a strong whirlpool of air which reaches the wind speed of up to 250 miles per hour. In case of tornado, people must be notified about its movement, so that they can protect their property and go to the shelter.
! .. y. ck is aa a D eb m Co
MOOO…
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READING THE SIGNS OF NATURE eople lived in fear of natural disasters for a long time. They believed these were caused by good or bad will of supernatural beings. That is why the first gods of ancient people were gods of sun, thunder, wind, rain... However, they observed the processes in the atmosphere and noticed that the weather changes according to certain patterns, as well as that these changes are preceded by a number of signs, such as the appearance of the sky and clouds or animal behaviour. Although they couldn’t give a scientific explanation to these phenomena, they passed them on to new generations in the form of folklore.
P
Ancient Greeks believed that their supreme god Zeus gathered up clouds on mountain tops and sent rain, lightning and thunder to the Earth.
SIGNS OF GOOD WEATHER The sky , clo uds and win d appear. • At midday small piles of clouds • The sky is reddish in the evening. ds appear. • In the evening wispy gold-like clou d blows. • A northern or north-eastern win • Wind decreases in the evening. The earth
The livi ng wo rld • Swallows fly high. • Bees return to the hive late in the evening. • Flowers in the meadow are open until late afternoon. • There are many bats in the evenin g. • Roosters crow a lot from the break of dawn.
• Dew lingers in the morning. • Smoke rises upright. • Morning fog dissapears quickly in the summertime.
Come back, you dirty rascals!
The sun, moon and stars • In the morning the sun is vivid yellow colour. • The sun isclear at sunset. • Stars are visible at night. • There are dark spots on the moon.
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The neighbours bats are flying about... A sign of good weather...
SIGNS OF BAD WEATHER The livi ng wo rld
The earth • Dew disappears suddenly. • The earth and roofs are smoking. • There are whirlpools of dust on a muggy day. • Smoke from the chimney goes toards the ground.
• Mosqitoes bte more than usual. • Earthworms appear. • Swallows fly low around houses and twitter. • Sparrows’ feathers bristle. • Flowers in the meadow are closed in the morning.
Nebo, oblac i, vetar • In the morning the sky is reddish in the east. • High fluffy clouds come from the west. • Big clouds shaped like a cone appear. • Wind increases in the evening. • Western, south-western and southern winds blow.
The sun, moon and stars • The sun is red and oval. m are visible. • Stars twinkle but not many of the the sun • There are red coloured circles around and moon.
You can check to what extent these natural phenomena are likely to be signs of good or bad weather. This will be easier if you make a table like the one below. Write down the signs you have noticed and your guess at possible development of weather conditions. If you regularly note down the signs you have learned about on these pages, as well as some other signs that you have heard about, you will be able to check how much each one of them is reliable when it comes to predictions about the weather. You should make notes in your calendar of signs for at least a couple of weeks every season. Date Signs of good/bad weather
There is a scientific explanation for most of these ancient beliefs. Signs of good weather are connected with high air pressure. When air pressure is high in the summertime, air is transparent, whereas in winter fog may appear. A decrease in air pressure is followed by an increase in air humidity, so the atmosphere isn’t transparent. Watson, where are you?
What is the weather we are expecting What was the weather like
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METEOROLOGICAL MEASUREMENT AND OBSERVATION eteorologists carefully measure parameters and observe
Mvarious atmospheric phenomena. The data they obtain helps For measuring you can use a personal weather station. It is an instrument used at home for measuring current temperature, relative humidity and atmospheric pressure. It also records the minimum and maximum temperature over a given period of time.
What you also need is a notebook, watch, compass and a camera you can use to take photos of clouds or some other atmospheric phenomena. If you have a computer, you can use it to obtain, store and process the data.
HEY! what time is it?
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them to understand those phenomena as well as to predict the weather. Air temperature is measured with a thermometer. In most of the world temperature is expressed in degrees Celsius. According to the Celsius scale, 0 degrees is the freezing point Hmm… of water, while 100 degrees is the Maybe boiling point. I could use clinical In the United States and some athermoother countries they use the meter… Fahrenheit scale (°F) according to which the freezing and boiling point of water are 32°F and 212°F respectively. Temperature (t) in Fahrenheit degrees can be expressed in degrees Celsius using the following formula: t°C = (t°F – 32) ⋅ 5 9
Atmospheric pressure is measured with barometer and the unit is millibar (1 mb). Average air pressure on the surface of the sea is 1,013 mb. An instrument which, beside the atmospheric pressure scale, contains the altitude scale too is called an altimeter. Mountain climbers and other nature enthusiasts find it very useful and so will you. Anemometer is used for With measuring wind speed. A this device measured value is expressed you can pick up four in meters per second and scoops of sometimes in kilometers per ice-cream at hour (1 m/s = 3.6 km/h). once! This instrument is not absolutely necessary because there is a straightforward way of assessing wind speed using the Beaufort scale.
A hygrometer is an instrument used for measuring relative humidity. A hygrometer with a pen that records temperature on a revolving cylinder is called hygrograph. The amount of precipitation is measured with a rain gauge. It is expressed either in millimeters or in liters per square meter. Some advanced models contain paper for recording the duration and intensity of precipitation. Some meteorological phenomena, such as the amount of clouds in the sky, thunder, fog, hoarfrost or dew, are assessed by observing.
Sweetheart, can you water the flowers, too?
set up the measuring instruments All over the world meteorological measurement is carried out in weather stations. Instruments are placed in an instrument shed, which is situated 2 meters above the ground. There are blinds on the walls and air wafts through them. The door faces north. There should be no tall buildings and trees nearby and the ground must be covered with grass because warm pavement and stone could affect measurements. The rain gauge should be placed on the post next to the shed. Its opening should be 1 m above the ground. If you have a big backyard, you Wow! can set up a real shed. However, a New appartment! darling we are measuring spot can be a balcony or moving! a window as well. But you should always bear in mind that instruments, especially thermometer, mustn’t be directly exposed to sunlight; they should be in mild shadow instead, so the measurement results will be more realistic.
Amateur meteorologists usually perform measurement three times a day; more precisely, at 7 a.m., 2 p.m. and 9 p.m. in winter and at 8 a.m., 3 p.m. and 10 p.m. in summer according to daylight saving time. The data obtained in weather stations have become easily accessible thanks to the Internet. You can visit the following websites: www.hidmet.gov.rs www.wmo.int www.wetterzentrale.de en.allmetsat.com If you are getting ready for a trip, you can go to www.weatheronline.co.uk and find out what the weather will be like there.
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A DIARY OF MEASUREMENTS AND OBSERVATION
According to some old diaries of measurements and observations, in 1893 on January 10 the temperature in Belgrade was – 26.2°C, while in the town of Sremska Mitrovica there was 308,9 mm of rainfall only in June 1954.
efore you start measuring, try and make a diary of measurements and
B observations. It is a table consisting of columns in which you should
write down values that you measure, as well as the symbols of all phenomena that you observe. Don’t forget to note down the date and the name of your measuring spot in the heading. It is recommended that you note its altitude, too. During the first week you should measure temperature and relative humidity only. You can do that three times a day. Later you can increase the number of parameters, as well as the number of times you measure them. For every phenomenon you observe, note down the time it occurred, how long it lasted and how intense it was. This will provide you with your own record on the hottest and coldest day, the amount of precipitation or some other phenomenon you are interested in. Moreover, the data will help you with your weather forecast.
Ha ha ha… Some ancient manuscripts of Earthlings’!
Measuring spot: ............................................................................................... Time of day
Morning
Hours
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Temperature (°C) Humidity (%) Atmospheric pressure (mb) Speed (m/s)
Wind Direction Type
Clouds Amount Type
Precipitation Amount
Other phenomena
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Date: ...............................................
Type Amount
7
8
9
Afternon 10
11
12
13
14
15
Evening 16
17
18
19
20
21
22
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how to assess a daily temperature range Temperature changes during the day. To find out more about these changes, try and carry out the following research. You should measure temperature every hour starting from the early morning until you turn in. Write the values you have measured in your diary, as well as the weather description – whether it was sunny, cloudy, windy… This information is sufficient to assess a daily temperature range. It is a numerical difference between the minimum and maximum values of temperature measured in one day. After noting down temperature values for a couple of days you will notice that it usually increases from the morning hours to the afternoon and then it decreases at night. What time is the temperature usually lowest and what time is it highest? The graph shows the daily temperature range in Belgrade on July 8, 2009. On this day there was a wave of cold air about noon and after 4 p.m. it started raining heavily. Try and see how it affected the temperature.
Oooh… It’s sweltering…
July 8, 2009, Belgrade
°C 28
The highest temperature ever measured was 58°C in El Azizia, Lybia on September 13, 1922. The lowest temperature of -89°C was measured in the weather station Vostok, the Antarctic on July 21, 1983. The highest temperature recorded in Serbia: 44,9°C, the town of Smederevska Palanka (215 m), July 24, 2007. The lowest temperature in Serbia: -38°C, the town of Sjenica (1,038 m), January 26, 1954.
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There are differences in temperatures between locations at different altitudes. Temperature usually is half a degree lower if altitude is 100 meters higher. This fact is extremely important for predicting the weather.
In winter months it is common for fog to stay longer in low regions, while at the same time the weather is clear at higher altitudes. In cases like this, the temperature is often higher on the mountain than in low regions.
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