WEATHER

El Nino & La Nina Weaken from east WINDS Strengthen from east Flows toward east WARM WATER Move farther west Mild and wet U.S. WEATHER Dry and warm in South Wet and cold in North Dry and cool AUSTRALIA WEATHER Mild and wet El Nino La Nina

Hurricanes HURRICANESPROPERTIES WIND SPEED 74 mph – 286 mph SIZE Up to 500 miles wide DURATION 2-4 weeks How does the ocean play a role in the formation? - A column of hot air from the Sahara that is three miles high spreads and picks up moisture from warm water (summer) and continues this process westward forming a tropical storm and then a hurricane.

Rainfall Patterns Rains all year long – from -5° to 8°Summer rain, winter dry – from 8° to 20° and -5° to -15°Dry all year – from 20° to 32° and -15° to -30°Winter rain, summer dry – from 32° to 45° and -30° to -40°Precipitation all year, more in summer – from 45° to 70° and - 40° to -65° Little precipitation all year – from 70° to 90° and -65° to -90°

Co Air Masses - Air masses are large bodies of air that are horizontally uniform in characteristics, like temperature and moisture content Continental = dry Maritime = moist Polar = cold Tropical = warm/hot Arctic = extremely cold mP cP mP mT cT mT

Fronts and Pressure Systems Front – boundary separating air masses, zone of transition Low pressure system – storm system, can travel thousands of miles and are responsible for the majority of precipitation High pressure system – Semi-permanent system that occupies the central portion of the Atlantic and Pacific – Large systems that represent large domes of cold air that follow lows Cold Front – cold air replaces warm air at the surface, most violent weather Warm Front – warm air replaces cold air at surface, usually northeast of a cold front Stationary front – doesn’t move, behaves like a warm front Occluded front – when cold front “catches” a warm front, mature storm systems

Fronts and Pressure Systems Occluded Front Cold Front Stationary Front Warm Front

Global Forces - Winds Coriolis EffectTrade Winds 90° 60° 30° 0° 30° The Earth’s Rotation causes surface currents to move in curved paths rather than a straight line. Affected by their latitude and the Coriolis Effect. In the tropics and poles, the winds blow from east to west. In the temperate climates, they blow from west to east. Polar Easterlies Tradewinds Polar Easterlies Tradewinds Westerlies

Global Forces - Water GyresDeep Ocean Currents Any large system of rotating ocean currents, particularly those involved with large wind movements -Deep cold currents move water toward equator -Cold water warms and rises to replace warm water leaving -Warm water travels on surface toward poles -Warm water replaces cold water