Chapter 2: Understanding the Weather
Hot or cold, sticky or dry, calm or stormy: weather shapes what we wear, eat and do. In this chapter we learn the elements of weather, read nature's old clues, measure temperature, rainfall, pressure, wind and humidity with real instruments, and see how weather stations and forecasts help keep people safe.
In this chapter you will
- define weather and name its elements
- match weather instruments to what they measure
- calculate temperature range and mean
- explain how forecasts and warnings help
Topics
- Weather and Its Elements NCERT 2.1
Weather is the state of the atmosphere at a given time and place; it happens in the troposphere.
- Measuring Temperature and Rainfall NCERT 2.2
Thermometers measure temperature (°C/°F); range = max − min, mean = (max + min) ÷ 2.
- Pressure, Wind and Humidity NCERT 2.3
Pressure falls with height; a barometer reads it in mb, and below 1000 mb is a depression.
- Weather Stations and Forecasts NCERT 2.4
Weather stations, including automated ones, record all elements regularly.
Key words
- Weather
- state of the atmosphere at a given time and place
- Troposphere
- lowest layer of the atmosphere, where weather happens
- Precipitation
- rain, snow, sleet or hail falling from the sky
- Atmospheric pressure
- the weight of the air above us
- Humidity
- water vapour in the air
- Barometer
- instrument for air pressure
- Anemometer
- instrument for wind speed
- Meteorology
- the scientific study of weather
Summary
- Weather is the state of the atmosphere at a time and place; it happens in the troposphere.
- Thermometers, rain gauges, barometers, anemometers and hygrometers measure its elements.
- Range = max − min; mean = (max + min) ÷ 2; wind moves from high to low pressure.
- Weather stations and IMD forecasts help people prepare for extreme weather.