4.8 (Earth's Geography & Climate) - 4.9 (El Nino & La Nina)

Climate

Determined by insolation; affected by latitude and atmospheric conditions.

Insolation

The amount of solar radiation reaching a given area.

Higher Latitudes

Regions that are cooler and receive less precipitation, particularly at 30°.

Equator

Region with intense insolation, higher temperatures, rising air, and high precipitation.

Rain Shadow Effects

Created when moist air rises and cools on the windward side of mountains, causing rain, while dry air descends on the leeward side.

Windward Side

The side of the mountain where moist air rises and drops precipitation.

Leeward Side

The side of the mountain that descends and experiences dry conditions.

Gyres

Large circular ocean patterns influenced by global winds.

Upwelling Zones

Areas where winds blow warm surface water away from land, drawing up cold, nutrient-rich water.

Thermohaline Circulation

Ocean circulation that connects all oceans by mixing salt, nutrients, and temperature.

El Niño Southern Oscillation (ENSO)

Shifts in atmospheric pressure and ocean currents in the Pacific between South America and Australia/Southeast Asia.

Normal Year

Condition when trade winds move water from West to East, leading to cooler upwelling off South America.

El Niño

Weakening of trade winds resulting in rising temperatures and precipitation in the Americas.

La Niña

Strengthening of trade winds resulting in increased upwelling and cooler conditions in South America.

Environmental Problems from El Niño

Suppressed upwelling reduces fishery productivity; cooler, drier conditions lead to droughts in Australia and Southeast Asia.