Environment
How Do Ecosystems Stay in Balance?
Ecosystems change continuously as organisms use energy, cycle nutrients, compete, cooperate, migrate, and respond to disturbance.
Environment
Learn about climate, weather, water, ecosystems, and sustainability.
Environment
How Does the Water Cycle Work?
Solar energy and gravity move water among oceans, air, land, ice, organisms, and groundwater through evaporation, condensation, precipitation, infiltration, runoff, and transpiration.
Environment
What Causes Climate Change?
Today's rapid warming is primarily caused by human greenhouse-gas emissions from fossil fuels, land-use change, industry, and agriculture.
Environment
How Do Hurricanes Form?
Tropical cyclones draw energy from warm ocean water, moist air, condensation, rotation, and organized thunderstorms under low wind shear.