Download Climate Patterns and Biomes

Climate of Rangelands
J. Peterson
Jim Peaco (www.nps.gov)
J. Schmidt (www.nps.gov)
Climate plays primary role
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Climate:
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Biome:
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Long-term patterns of temperature & precip
Weather = short-term variation in temp., precip.
wind, humidity, etc.
Largest terrestrial ecosystem that is easily
recognizable.
Prairies, shrublands, woodlands, forests, etc.
Ecosystems:
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Community of organisms & abiotic environment
How does climate affect global
vegetation patterns?
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Affects plant biomass (amount of vegetation)
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Affects types of plants that will grow:
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Drives photosynthesis
Determines growing periods (frost-free period)
Trees need more water than shrubs, forbs &
grasses.
Some plants like it hot & some like it cold.
Depends on plant physiology.
Influences soils texture & structure.
Climate Affects Vegetation
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Rangelands
evolved where
precip was
insufficient for
forests, but
too much for
barren deserts.
Robert Whittaker’s classification of biomes, based on annual precipitation, temperature
Variation in Annual Precipitation Across U.S.
Variation in Precip
L.A. Sharp Experimental Area –Malta Idaho
Effective precip
= when precipitation
is usable
Min Precip = (1989) 6.6 inches Max Precip = (1982) 23.6 inches Average = 14.9 inches
Geographic Climate Regions
Great
Basin
Figure by K. Launchbaugh
Grassland &
Savannas
Deserts &
Semideserts
Mediterranean
Deserts &
Semideserts
Topographic Effects
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Mountains can create Orographic Barriers
with Rain Shadows on the leeward side
From http://web.mst.edu/~rogersda/umrcourses/ge301/
Hadley Cell Effect
Atmospheric circulation
patterns between
circulation between the
equator and 30
latitude.
http://people.eku.edu/davisb/Africa/Hadleycell.jpg
Hadley Cell Effect
Creates bands of moist
or dry zones around the
globe.
http://serc.carleton.edu/images/eslabs/weather/hadley_cells_semi_permanent.jpg
Equator
30
http://www.whymap.org/
Continental Land Effects
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Lands around large bodies of water tend to
have climates with:
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Mild temperatures
Abundant precipitation (moist or mesic)
Centers of continents are often:
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Extreme temperature variation (summer to
winter)
Dry
Continental Patterns
http://earthobservatory.nasa.gov/Features/BlueMarble/Images/land_shallow_topo_2048.jpg
Watch Global Circulation video at: www.youtube.com/watch?v=qh011eAYjAA
Rangelands of the World
Summary of Climate
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Patterns of precip. & temp drive patterns of
vegetation.
Geographic effect
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Altitude and latitude are important
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Orographic barriers & rain shadows
Hadley cells
Continental effects