Chapter 4: Weather and Climate Notes

Weather: condition of the atmosphere at a particular place and time (short term) Climate: average conditions of temperature, precipitation, winds and clouds in an area (long term)

What Causes Climate? Temperature (cold or warm climate) Precipitation (dry or humid climate)

Factors Affecting Temperature Latitude Altitude Distance From Large Bodies of Water Ocean Currents

Convection In the atmosphere, the air is heated by land & water (which absorbed solar energy and changed this to heat). The warm air rises, cools in the upper troposphere and sinks back to Earth to be warmed again. This makes a current.

Latitude Latitude: The distance from the equator measured in degrees There are three convection areas: Tropical Zones: warm climates Temperate Zones: ranging temperatures Polar Zones: cold climates

Convection Currents Convection happens on a global scale in the atmosphere and causes global winds (6.4.9). These winds then move weather systems and surface ocean currents in particular directions.

Global Wind Patterns

Land and Sea Breezes On a smaller scale, convection currents near bodies of water can cause local winds known as land and sea breezes.

Altitude Altitude: elevation above sea level High land areas have cooler climates Higher altitudes = cooler temperatures Lower altitudes = warmer temperatures

Distance From Large Bodies of Water Marine Climates: warmer winters and cooler summers Continental Climates: colder winters and warmer summers

Ocean Currents Oceans and lakes can affect temperatures/climate Ocean Currents- streams of water within the ocean that move in regular patterns 3 examples: Gulf Stream, North Atlantic Drift, California Current

Ocean Surface Currents The surface currents of Earth’s oceans that circulate warm and cold ocean waters in convection patterns also influence the weather and climates of the landmasses nearby.

Gulf Stream Current This warms SC & even Great Britain. This is like sitting near a hot tub when it’s snowing. You can get warm by just being near the warm water.

California Current This cools the west coast. This is like sitting near the lake when it’s hot. You can get cool by just being near the cool water.

Factors Affecting Precipitation Prevailing Winds Mountain Ranges

Prevailing Winds movement of air masses caused by directional winds in a region The amount of water vapor in an air mass influences how much rain or snow will fall The amount of water vapor in the prevailing wind depends on where the wind comes from

Mountain Ranges Air forced up the mountain cools, condenses, and creates clouds Falls as precipitation on windward side Leeward side of mountain has drier conditions

Microclimates Microclimates: small region with specific climate conditions Examples: parks, cities, areas near lakes or ponds, gardens, etc.