Understanding the Weather Class 7 Question and Answers with ncert solution and notes.
Q. How can we measure and monitor the weather around us?
Ans – We can measure and monitor the weather around us using a combination of instruments, technology, and observational techniques.
Thermometer = Temperature
Barometer = Air Pressure
Hygrometer = Humidity
Anemometer = Wind
Wind Vane (or Weather Vane) = Wind Direction
Rain Gauge = Precipitation
Q. How do weather predictions help us prepare for events like heavy rain, storms, drought and heat waves?
Ans – Weather predictions are essential tools that help individuals, communities, and governments prepare for and respond to extreme weather events like heavy rain, storms, droughts, and heat waves.
a) Forecasts alert people and authorities to prepare for potential floods. People can avoid unnecessary travel or delay trips.
b) Airlines and transport services cancel or reroute to ensure safety. Sirens, news alerts, and text messages notify people to take shelter during storm.
c) Authorities can plan water rationing, recycling, or storage. Encourages water-saving behaviors in homes and industries.
d) Outdoor work hours may be reduced or rescheduled; schools might close or change activities.
Q. What is weather?
Ans – Weather is a state of the Earth’s atmosphere at a particular time and place.
Q. What are the elements of weather?
Ans –
a. Temperature: How hot or cold the atmosphere is.
b. Precipitation: Any form of water, such as rain, snow, sleet or hail, that falls from the sky.
c. Atmospheric Pressure: The weight of the air above us, felt on the Earth’s surface.
d. Wind: The movement of air, including its speed and direction.
e. Humidity: The amount of water vapour in the air.
Q. What do you think could be some other reasons to measure the weather more precisely?
Ans – Measuring the weather more precisely benefits not just emergency preparedness, but a wide range of other areas that affect our daily lives, economy, safety, and environment.
a) Helps us understand how storms form, why droughts occur, or how ecosystems respond to weather changes.
Pest and Disease Control: Certain weather patterns lead to outbreaks — accurate data helps prevent loss.
b) Road Travel: Snow, fog, and ice forecasts prevent accidents and guide road maintenance crews.
Renewable Energy: Solar and wind power generation depends on sunlight and wind conditions. Precise data helps manage supply and storage.
c) Better Forecasting Models: More precise data helps reduce false alarms and improves trust in weather alerts.
Q. Why do you think it would be important to measure atmospheric pressure? Who are the people most likely to use such measurements?
Ans – Measuring atmospheric pressure is incredibly important because it gives us critical information about the state of the atmosphere and helps predict short-term weather changes.
Sudden drops can warn of severe weather, like cyclones or hurricanes.
Weather models, altimeters, and GPS systems often require barometric pressure for improved accuracy.
- Meteorologists = To forecast weather and analyze atmospheric systems.
- Pilots and Air Traffic Controllers = For altitude readings and flight planning.
- Mountaineers and Hikers = To estimate elevation and prepare for altitude sickness.
- Sailors and Mariners = To detect approaching storms or pressure systems at sea.
- Farmers = To plan agricultural activities based on changing weather.
Q. Jyotsna is deciding what clothes to pack for her school trip to Mumbai in June. She looks at the weather forecast, which predicts 29°C and 84% humidity. What would be your advice to her?
Ans –
Based on the forecast for Mumbai in June — 29°C temperature and 84% humidity — here’s some practical advice for Jyotsna on what clothes to pack and how to stay comfortable:
29°C is warm, and combined with 84% humidity, it will feel hot, sticky, and sweaty.
Mumbai in June is monsoon season, so she should also be prepared for sudden rain and damp conditions.
Do it Yourself.
Notes :-
Weather is a state of the Earth’s atmosphere at a particular time and place.
What is an atmosphere?
It is the layer of gases that surround Our planet, Earth.
The layer closest to the surface of the Earth is called the ‘troposphere’.
All land-based plants and animals (including humans!) live and breathe in ‘troposphere’.
The troposphere extends to a height of 6 to 18 kilometres from the ground; it is less thick at the poles (where the cold air contracts) and thicker in the tropical zone (where the warmer air expands).
Name the elements of weather :
a. Temperature: How hot or cold the atmosphere is.
b. Precipitation: Any form of water, such as rain, snow, sleet or hail, that falls from the sky.
c. Atmospheric Pressure: The weight of the air above us, felt on the Earth’s surface.
d. Wind: The movement of air, including its speed and direction.
e. Humidity: The amount of water vapour in the air.
Sleet:Frozen or partly frozen rain.
Hail:Small, hard balls of ice that fall from the sky like rain.
Water vapour:Water vapour is water in gaseous instead of liquid form.
Forecast: To predict or find out in advance (in our case, the weather).
Meteorology:Meteorology is the systematic study of weather and its evolution. This study is the basis for weather forecasting.
Ambient: Of the immediate surroundings.
Statistics: The technique of gathering and analysing information or data in order to be able to detect patterns, understand events or make predictions.
Humans have closely observed Nature and learnt to read her signals to forecast the weather. Observing birds flying low, ants carrying eggs, squirrels gathering nuts, frogs croaking loudly, or even the opening and closing of pine cones, provided valuable information about coming rain or storms.
Different types of thermometers used for measuring the temperature—the clinical thermometer and the laboratory
thermometer.
Range of temperature or the maximum temperature minus the minimum temperature during a particular period of
time (usually 24 hours).
Mean daily temperature or the maximum temperature plus the minimum temperature of the day divided by two.
The India Meteorological Department was set up in 1875. Its motto is ādityāt jāyate vriṣhti, which means, “From the sun arises rain.”
The amount of rainfall is measured with the help of an instrument called a rain gauge.
The atmospheric pressure is higher near the sea coast and lower as we go higher up into the mountains.
The instrument used to measure atmospheric pressure is called
a barometer.
The unit they display is generally the millibar (abbreviated as mb). The normal atmospheric pressure at the sea coast is around 1013 mb; a pressure below 1000 mb indicates a depression.
Wind is the movement of air from areas of high pressure to
areas of low pressure. Speed and direction are two important
factors when we describe the wind.
A wind vane (or weather vane) has a rotating arm with a pointer at one end and a tail at the other.
The simplest instrument to measure the wind direction and
speed is the anemometer.
Humidity – It refers to the amount of water vapour present in the air. It also depends on factors like temperature, wind, pressure and location.
Humidity of the air is measured as relative humidity.
hygrometer
The measurement of humidity is of great importance in many
industrial processes, such as food processing. Museums also
monitor humidity as they need to maintain a dry environment
to preserve their exhibit.
A weather station brings all these instruments together, making it easy to measure and track the weather. Readings of all the measurements are taken at regular intervals, which helps in mapping and forecasting the weather.
An Automated Weather Station (AWS) is a self-operating
system that uses various sensors to measure and record weather
data, such as temperature, humidity, wind speed and direction,
precipitation, and atmospheric pressure.
Such stations are widely used in fields like agriculture, aviation, navigation, environmental monitoring, and so on, providing accurate and timely weather information without the need for human intervention.
In 2023, the National Disaster Management Authority set up an AWS at a glacial lake of Sikkim at an altitude of more than 4800 metres above sea level.
Predicting the Weather
Meteorologists collect data using these instruments over
long periods of time. They study the data and use scientific methods to try and predict the weather. Such predictions are
very important nowadays, as climate change makes extreme
weather, such as droughts, floods, cyclones, etc., more frequent. Accurate predictions help us to be ready for such events. They
also enable local governments to mobilise resources and prepare
for any disasters.