WEATHER AND CLIMATEChapter 3

Four factors or elements that affect climate are:o Latitudeo Wind Currentso Proximity to Watero Elevation

Latitude

CLIMATE ZONES Low Latitudes - Tropical Wet and Tropical Wet

and Dry. Middle Latitudes - Mediterranean, Humid

Subtropical, Humid Continental, Marine West Coast.

High Latitudes - Subarctic, Tundra, Icecap Varies - Semiarid, Arid, Highland

WIND CURRENTS

Wind and ocean currents distribute the sun’s heat through convection, the transfer of heat in the atmosphere through upward motion of the air.

AIR PRESSURE AND WINDS

Air is a fluid Warmer air is less dense Air moves from dense to less dense conditions Ex.: Land-sea breezes

Warmer air “holds” more water Low pressure=warm air=precipitation High pressure=cold air=dry air

WEATHER FRONTS

Front: the boundary that separates two air masses of different temperatures.

Precipitation often occurs along these fronts

PROXIMITY TO WATER

Areas near the ocean have a milder winter and a cooler summer.

Ocean currents are like rivers in the ocean. Warm water flows away from the equator and cold water flows toward the equator.

OCEAN CURRENTS

Follow same circular pattern (driven by wind)

Warm currents flow away from equator, pile up on

eastern shores ex. Gulf Stream

Cold currents flow towards equator, cause upwelling

PROXIMITY TO WATER

One important ocean current is:o The North Atlantic Drift - This ocean

current warms Western Europe.

ELEVATION

Elevation influences temperature. As you go up in elevation the temperature becomes colder because the atmosphere is thinner. Areas with very high elevations can have vegetation similar to the arctic.

Ms. Frizzle explains…

On the windward side of a mountain the orographic effect leads to more precipitation

On the leeward side of a mountain, the rain shadow effect leads to less precipitation and warmer temperatures. They are often deserts.