Weather & Climate Mr. Nero CGC1D1

Weather vs. Climate Weather Generally defined as the condition of the atmosphere over a short period of time Usually 1 day Climate Condition of the atmosphere considered over a long period of time

Factors Affecting Weather & Climate 6 major factors that affect weather and climate. They can be on two different scales: Global Local

The 6 Factors Latitude Ocean currents Winds and air masses Elevation (altitude) Relief (presence of physical features) Nearness to large bodies of water

Latitude As latitude increases (north and south of the equator) the temperature decreases Has to do with solar radiation and the angle of incidence angle the suns rays hit the surface of the earth

Air cools at approximately 1degC/100m Elevation (Altitude) The higher the elevation, the cooler the temperature Air expands as it rises from the earth’s surface. The air expands because the pressure on the outside of the air mass is less than that of the rising air mass. As the air expands there is more space for molecules to move around in so their energy is transferred, resulting in cooling of the air mass. Air cools at approximately 1degC/100m

Ocean Currents If ocean currents are warm, they will keep both winter and summer conditions on the land warmer than expected (i.e. the Gulf Stream). Cold currents such as the Labrador Current have the opposite effect.

Winds and Air Masses Winds can move cool air to moderate a hot area, or moist air to bring rain to a dry area. Basic principle – they move dense, heavy air from high pressure areas towards areas of low pressure where the air is less dense, lighter and rising. Air masses take on the characteristics of the surface they are sitting over (i.e. an air mass over and ocean in the tropics will be warm and moist)

Relief Physical features have a considerable influence on weather and climate Mountains can act as a barrier where the windward side would get a lot of rain and the leeward side would receive little rain Flat plains enable cold air, dry air from the north to reach far into North America

Bodies of Water Oceans and Great Lakes Act in the opposite was of air masses Water heats and cools much slower than land Lakes tend to be cool when the land is warm and vise versa Moderating effect