Sometimes, the surface of the Pacific Ocean warms up, causing changes in the weather in some areas. This phenomenon is called El Niño. El Niño causes the amount of rainfall in some parts of the United States and South America to increase. It also causes droughts to occur in Southeast Asia and Australia. Droughts occur when an area receives less rain than it normally does over a certain period. Explain how Earth’s spheres may be affected by the droughts brought on by El Niño.

Sample Response: When there is less rainfall, land, which is part of the geosphere, becomes dry. When there is not enough water, plants will not get the nutrients they need from the soil and animals will not get enough water, and they will die. Both plants and animals are part of the biosphere. Less precipitation would also mean less water in lakes and groundwater, parts of the hydrosphere, and less evaporation. The atmosphere may also be affected due to less water vapor.