Download Climate Factors

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Climate – a region’s weather
conditions average over thousands of
years
Includes temperature and moisture
averages
1. Average temperature over the year
2. Temperature range throughout the yeardifference between the hottest and
coldest months of the year
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The average yearly precipitation is less
than the potential evapotranspiration.
Affected by the temperature – high
temperature but low rainfall = arid
Examples - Deserts
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Average rainfall is greater
than the potential
evapotranspiration
A lot of rain is not
needed…as long as there is
more rain than
evapotranspiration
Examples - rainforest
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Latitude – affects the temperature

Near poles – (high latitude) the angle of the sun
changes a lot during the year, creating a wide
temperature range, but cooler temperatures overall

Near equator – (low latitude) the angle of the sun is
high most of the year, creating steady but warm
temperatures all year long.
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Latitude - affects moisture

Low pressure areas near equator
and mid latitudes creates warm
rising air, clouds and
precipitation

High pressure areas near poles
and 30o create dry sinking air
and deserts.
See ESRT diagram wind and
moisture belts
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Large Bodies of Water -Marine climate –
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Wind blows moist air from over the
ocean of large lakes. Being near water
will also make temperatures fluctuate
less during year than an inland area of
similar latitude (cooler summers and
warmer winters) like Long Island
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Large Bodies of Water –Continental climate –
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Wind blows dry air over vast stretches
of land. Being inland (far from water)
will also make temperatures fluctuate
more during year than an marine
location of similar latitude (hotter
summers and colder winters) like St.
Louis.
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Prevailing winds blow air masses across
the US from southwest to Northeast
(west to east)
 West coast – receives warmer wet air
(marine)
 East coast – mostly receives dryer air
(continental) except for Long Island
(marine)
 Lake effect snow – near great lakes in
upstate NY because of wet air being
clown from the great lakes
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Ocean Currents
 Warmer water from the equator carried to higher
latitudes
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Cooler water from near poles carried toward equator

See ESRT Surface Ocean Currents
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Elevation
 Higher elevation have cooler
temperatures and more moisture
because of increased cooling of the air
and more condensation
 Examples – Catskill and Adirondacks
in NY
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Mountains
Mountains can block cold or warm air passing
 Windward side – “water” or “wet” side forces air up
and to condense, creating precipitation
 “Leeward side – “land” or “dry” side because once
the air passes over the mountain it descends, warms
and precipitation stops.

 Examples –Champlain Lowlands are on the leeward
side of Adirondack Mountains. Also, Las Vegas desert
is on the leeward side of the Sierra Nevadas.
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Cloud Cover –
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Clouds near the
equator block some
insolation, making it
slightly cooler than
the 30o latitude dry,
cloudless areas.
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Pollution adds
particles to air that
increases
condensation,
creating haze or
clouds which
decrease the
transparency of the
air (i.e cools it off)
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Vegetation – Plants
and trees increase
transpiration,
making areas
humid and cooler
from shade.
When
deforestation
occurs, the area
gets much hotter
and dryer
Jan. 2011 Regents