1. Prepared by: Ms. Siddhi Hegde Pawar Public School Kandivali

3. Introduction Weather affects everyone’s life. Weather is very commonly used term. Long ago, prediction of weather was done by observing clouds and the behaviour of animals. Prediction of climate started way back in 1700s by climatologist Thomas Jefferson Modern day scientists can predict weather with greater accuracy with the help of satellites.

4. Weather 1) It is day to day or short term state of atmosphere at any time. 2) Weather is hour to hour and day to day condition of the atmosphere. 3) It is the way the earth’s atmosphere behaves. 4) It may be hot, cold, wet, dry, calm, stormy, clear or cloudy

5. Weather is made up of three main components – 1) Temperature 2) Movement of air 3) The amount of water vapour in the air.

6. Climate 1) It is average of weather conditions for a particular region observed over a period of not less than 30 years 2) Climate is long term or typical pattern of weather in a particular area. 3) It varies enormously in different parts of the world. 4) The term climate includes averages of precipitation, temperature, humidity, sunshine, wind, velocity, fog, frost, hail, storms and other phenomena of weather that occur over a long period, in a particular place.

8. Importance of weather forecasts: Weather forecasts are useful for- Farmers Fishermen Aviators Navigators General public Weather forecasts give advance warning about storms, cyclones, rain, wind etc.

9. Weather stations Everyday each weather elements is continuously recorded at weather stations across the country with the help of different weather instruments. Weather forecast The predictions about different elements of weather are collectively called weather forecast. People are informed about weather forecast through newspapers, radio and television.

10. Meteorology The scientific study of the elements of weather is called meteorology. Meteorologist The people who conduct these scientific studies are called meteorologists.

11. Elements of weather Temperature Atmospheric pressure Rainfall Moisture Wind speed Wind direction Clouds Sunshine

12. Temperature The degree of coldness or hotness of the air that surrounds us is called as temperature.

13. Measuring Temperature Thermometer It is used for measuring temperature of free moving air. In thermometer mercury or alcohol is used

14. Two scales of measuring temperature

15. Six’s maximum & minimum Thermometer

16. Thermometers in Stevenson screen It allows the air to move freely but shields the thermo meter from direct sunlight

17. Thermograph An automatic thermometer for continuous recording of the temperature

18. Air Pressure The pressure exerted by the weight of air on the earth’s surface.