CLIMATE

What is Climate?  Climate is the average conditions of temperature and precipitation in a particular area.  Caused by many factors including:  Greenhouse Effect  Latitude  Winds and ocean currents  Land Masses  Elevation

Greenhouse Effect  The greenhouse effect occurs when heat is retained by a layer of greenhouse gases in the atmosphere.  Greenhouse gases include:  Carbon dioxide  Methane  Water vapor  Without these gases, Earth would be 30 ⁰ C cooler than it currently is.

Effects of Latitude  Because Earth is a sphere that is tilted on its axis, solar radiation strikes different parts of the Earth’s surface at an angle that varies throughout the year.  Different latitudes on the earth receive different amounts of light.

Climate Zones  There are three main climate zones:  Polar zones Cold areas where the sun’s rays strike Earth at a very low angle Between 67 ⁰ and 90 ⁰ North and South  Temperate zones More affected by the changing angle of the sun Ranges from hot to cold depending on the season Between Polar Zones and Tropical Zones  Tropical zones Receive direct or nearly direct sunlight year-round Between 24 ⁰ N and 24 ⁰ S.

Winds  Unequal heating of the Earth’s surface creates winds.  At the equator, the air is heated and rises.  At the poles, the air is cool and sinks.  This movement of air causes heat to move through different regions.

Ocean Currents  Like winds, ocean currents are caused by unequal heating of the Earth’s surface  Warm water at the equator rises to the surface, while cool water at the pools sinks to the ocean floor.  Surface water is moved around by winds.  Ocean currents transport heat energy within the biosphere and affect the temperature of the air above them.

Land Masses  Air travels with the winds in specific patterns  These patterns can be disturbed by land masses.  Mountain ranges cause moist air to rise  As it rises, it cools and moisture condenses causing precipitation  When the air reaches the far side of the mountain, it has already lost most of its moisture  This results in what’s called a “rain shadow” which is an area with dry climate on the far side of the mountain.

Elevation  As you increase in elevation, the atmosphere becomes thinner.  As air expands, it cools  Less atmosphere to hold in heat  Less atmosphere to protect against the suns rays

BIOMES

Climate vs. Microclimate  Climate is the average conditions of temperature and precipitation in a particular area.  Microclimate: the climate within a small area that differs significantly from the area around it.

Major Biomes  Temperate grassland  Tropical savanna  Desert  Temperate forest  Tropical rainforest  Taiga (boreal forest)  Tundra

Major Biomes

Temperate grassland  Rich mix of grasses  Fertile soil  Warm/hot summers  Cold Winters  Large herbivores

Tropical savanna  Covered with grasses  Scattering of trees  Compact soil  Seasonal rainfall  Frequent Fires

Desert  Dry (25cm or less)  Sandy soils  Cacti and bushes  Small mammals &reptiles

Temperate forest  Cold winters  Warm summers  Year round precipitation  Fertile soils

Tropical rainforest  Hot and wet  Nutrient poor soils  Dense wildlife

Taiga (boreal forest)  Long, cold winters  Short, mild summers  Moderate precipitation  High humidity  Primarily coniferous forests

Tundra  Strong winds  Low precipitation  Short and soggy summers  Long, cold, dark winters  Permafrost