Climate & Vegetation Chapter 3
Earth-Sun Relationships Axis – imaginary line that run through the center of the Earth Earth’s axis is tilted 23 ½ ° Earth’s tilt affects the climate since all places do not receive the same amount of direct sunlight.
Earth-Sun Relationships Revolution – orbit around the Sun Earth’s revolution takes 365 ¼ days. Revolution causes the changing seasons.
Earth-Sun Relationships Rotation – spinning on its axis The Earth’s rotation takes 24 hours. Rotation causes day and night.
Earth-Sun Relationships Equinox – either of the 2 times each year (spring and fall) when day and night are of nearly equal length everywhere on Earth Solstice – either of the 2 times a year (summer and winter) when the sun appears directly overhead at noon to observers at the Tropics of Cancer and Capricorn
Weather vs. Climate Weather - condition of the atmosphere at a particular location and time. Climate – the term for weather conditions at a particular location over a long period of time
Weather Extremes Hurricanes Tornadoes Blizzards Droughts Floods
Factors that Affect Climate Latitude – the amount of direct sunlight affects climate Places closer to the Equator receive more direct sunlight than areas closer to the poles which receive slanted rays.
Factors that Affect Climate Landforms – mountains can block precipitation which can affect climate. This is called the orographic effect (rain shadow). Ex. - Sierra Nevada range and the Mojave Desert Windward side – wet Leeward side - dry
Factors that Affect Climate Wind currents Prevailing winds are winds that blow in a fairly constant pattern. The direction of the winds can determine what type of weather patterns an area will see.
Factors that Affect Climate Ocean currents – cold and warm “rivers” of water known as currents, flow in the ocean Cold currents cool the lands they pass while warm currents have a warming effect. Ex. North Atlantic Drift flows near western Europe and gives the area a mild climate despite its northerly latitude
North Atlantic Drift
Factors that Affect Climate Proximity to large bodies of water Water is slower to heat and cool than land. Water temperatures are more constant and uniform than land temperatures. Temperatures of land areas located near oceans do not change as much as interior land areas.
Factors that Affect Climate Proximity to large bodies of water Example: City Newport, OR Rapid City, SD Location 44°N, 124°W 44°N, 103°W Average Jan. 44° F Jan. 22° F Temperatures July 57° F July 72° F
Factors that Affect Climate Elevation – for every 1,000 feet gained, the temperature drops about 3.5° F. Mt. Kilimanjaro in Africa is located near the Equator, but is covered with snow and ice
Types of Precipitation Convectional –hot, humid air rises and cools losing its ability to hold water (ex. Tropical rainforest) Orographic – warm moist air is forced up when passing over high landforms Frontal – 2 fronts of different temperatures meet
Convectional Precipitation
Frontal Precipitation
Orographic Precipitation
Four Types of Vegetation Forest Grassland Desert Tundra What kind of trees are these?
Forest Tropical rainforest Deciduous forest – broadleaf, such as maple and oak Coniferous forest – cone bearing, evergreens Chaparral Chaparral - California
Forest
Grassland Tropical grasslands (savannas) Temperate grasslands (prairies, steppes, pampas)
Grasslands
Desert A desert can occur where there is a lack of precipitation, less than 10 inches a year. Deserts can be cold, they do not have to be hot and sandy. Vegetation – plants that can conserve water & withstand heat such as cacti & sagebrush
Desert
Tundra Alpine tundra Arctic tundra Vegetation – includes mosses & lichens