Weather and Climate

Factors...
- Atmospheric Circulation
- Ocean Currents

HOW??

- The sun's rays provide both light and heat to Earth, and regions that receive greater exposure warm to a greater extent. This is particularly true of the tropics, which experience less seasonal variation in incident sunlight. Moisture-laden tropical air warms, becomes less dense, and rises. But as air reaches the upper levels of the atmosphere, it cools. Water molecules condense to form clouds and eventually fall as rain. Warm air rising from Earth's surface pushes the air mass away from the equator, and releases its moisture as precipitation as it travels pole-ward.
- Trade winds blow warm surface waters in tropical oceans and seas from east to west. Warm water pools along the west coast of continents, which sets up a temperature gradient across the ocean surface. Under normal conditions, the western Pacific is about 8°C warmer than the eastern Pacific, and this gradient contributes to the formation of clouds and precipitation in Australia, Indonesia, and parts of Africa. Disruption of this temperature gradient creates the event known as El Niño.