Weather Patterns and Climate Bates

Convection Currents Convection currents occur because warm air near Earth’s surface rises and cools as it goes up.

Convection Regions Tropical Region-equator to 30°N latitude Northern regions are: Tropical Region-equator to 30°N latitude Temperate Region-30° to 60°N Polar Region-60° to north pole (90°)

Land and Sea Breezes Sea breezes and land breezes are local winds caused by convection currents near a body of water.

Land and Sea Breeze land and sea breeze animation Unequal heating of air over land and water results in breezes near shorelines. While the land is warm during the day, air above it rises, and a cool breeze blows in from the sea. As the land cools off at night, air pressure over it increases, and a cool land breeze blows out to the sea.

Surface Currents The surface currents of the earth’s oceans circulate warm and cold ocean waters in convection patterns These currents affect the weather and climates of landmasses. The warm Gulf Stream influences the east coast of the US. The cold California current influences the west coast of the US.

Global Winds and Jet Stream

Global Winds Coriolis effect-Due to the spinning of the earth, global winds curve. Found in each convection area In each global wind belt, the direction of the winds and air movement affects weather conditions

Global Wind Belts Trade winds-blow warm, tropical air from east to west in tropical regions. Westerlies-blow from west to east in temperate regions and are effected by seasons. Tropical weather systems begin moving with trade winds and can then move with the westerlies. Polar winds-blow cold air northeast to west in the polar regions.

Jet Stream A fast moving ribbon of air that moves west to east. It dips and bends and changes positions. Air masses and weather systems are moved by this fast moving air. The polar jet stream brings cold polar conditions from the north. The subtropical jet stream brings warm tropical conditions from the south.