Long ago, people predicted the weather by observing changes in the behavior of plants and animals. For example, they could tell that hot and dry weather is approaching when pine cones open to scatter their seeds. Frogs sleeping underground during long warm days come out when it rains. Today, meteorologists (people who study the weather) gather information from weather stations at sea, on land, in the air and even in space to predict the weather. They use different instruments for observing different weather elements.

The Earth is surrounded by a blanket of air called atmosphere. The condition of the atmosphere at any given time is called weather. When we ask about the weather, we usually want to know how hot or how wet it is. The sun’s heat stirs the atmosphere and makes the air moves. Moving air carries heat and water. Changes in the temperature and water in the air cause some changes in the weather.

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Air temperature. When the air around you is warm, then you fell warm. When the air around you is cold, then you fell cold. Air temperature is the measure of how hot or cold the air is. Why does air temperature change?

The sun gives off energy in the form of light and heat. During daytime, the side of earth facing the sun receives heat directly from the sun, making the land and water warm, this in turn makes air temperature rise. During nighttime, the side of Earth facing away from the sun loses its source of heat. The air temperature drops.

Air temperature also changes with the seasons. In summer, the days are longer than nights. During this time, the Earth receives more heat, so, the temperature of the air is higher. Air temperature also changes with altitude or elevation of a place. It is cooler on top of a mountain than in the surrounding lowlands. Hence, during summer, many people from the lowlands go up the high lands because it is cool there.

To take air temperature, place a thermometer in the shade and not in the sunlight. Each time you take a reading, keep the thermometer in place for several minutes.

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Did you know that Tree crickets are called the “poor man’s thermometer”. It you count the number of chirps a cricket makes in 15 seconds and add 37, the sum will be almost the same as the temperature (in degrees Fahrenheit) outside. This is because temperature directly affects a cricket’s rate of activity.