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• 4th Grade Home
• Cloud Watching
• Forecasting the Weather
• Pushing Down
• Severe Weather
• Precipitation
• Create a Weather Graph!
• Windward Ho
• Meteorologist Tools
• Here Comes the Sun!
• Weather Prediction
• Charting the Weather
• Science Language

Weather Observations - Here Comes the Sun!

The title above is just one of many songs that have been written about the sun. The sun is responsible for the abundance of life that is found on Earth. Without the energy provided by the sun, this planet would be a dark, cold lifeless place. The sun is also responsible for the weather on Earth. One kind of energy we get from the sun is heat. The sun does not directly heat the air, rather the air is heated by the land or water beneath it. Because land and water heat and cool at different rates, the air also heats unevenly. This uneven heating of the air causes wind as well as changes in the weather.

You're the scientist!
What do you think will heat up faster - soil or water? Record your hypothesis and then perform the following activity to find out if you were correct:

Materials:

• Two identical paper or plastic cups
• Water
• Soil
• Two thermometers
• Lamp

Procedure:

1. Fill one cup half full of water and one cup half full of soil.
2. Let the cups sit in a room for a couple of hours. Make sure the sun isn't shining on them. You want them both to have time to become room temperature.
3. Place a thermometer in each cup. Be sure the bulb of the thermometers is deep into the water and the soil.
4. Record the initial temperature of each thermometer.
5. Place both cups in the direct sun, or under a bright lamp. Make sure both cups get equal amounts of light.
6. After 15 minutes, record the temperatures of each thermometer.
7. Place both cups in the refrigerator for 15 minutes.
8. Record the temperatures of each thermometer.
9. Explain your findings. Which material heats up faster? Which material cools down faster?
10. Graph your results.

WARMING UP!
While performing this activity you probably noticed that the soil warmed up faster than the water. You probably also noticed that the soil cooled down faster than water. The same is true on Earth. Land heats up faster than water. The air over warm or hot land heats up more rapidly than air over the oceans in the summer. The air above the land rises and the cooler air over the ocean moves in from the ocean to take the place of the rising air over the land. That is why it is usually cooler near the ocean in the summer.

COOLING DOWN!
The opposite is true in the winter. The area very near the ocean in the winter will not be as cold as the area further in land. The ocean will not cool down as fast as the land does. San Franciso, California is usually cooler in the summer and warmer in the winter than Delta, an Utah because Delta is not near the ocean. The air temperature over Delta is affected by the land of the Great Basin. The air temperature over San Franciso is affected by the water over the Pacific Ocean. There are other things that affect temperature, but this is one big thing that makes a difference.