Transcript 50B2-Weather

CHAPTER 50 AN INTRODUCTION
TO ECOLOGY AND THE BIOSPERE
Section B2: Factors Affecting the Distribution of
Organisms
5. Temperature and water are the major climatic factors determining the
distribution of organisms
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5.Temperature and water are the major
climatic factors determining distribution of
organisms
• Climate is the prevailing weather conditions in an
area.
• Temperature, water, light, and wind are major components
of climate.
• Climate and biomes.
• Climate determines the makeup of biomes, the major
types of ecosystems.
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• Annual means for
temperature and
rainfall are
reasonably well
correlated with
the biomes we
find in different
regions.
Fig. 50.10
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• Global climate patterns.
• These are largely determined by sunlight and the
planet’s movement in space.
• The sun’s warming effect on the atmosphere, land,
and water establishes the temperature variations,
cycles of air movement, and evaporation of water
that are responsible for latitudinal variations in
climate.
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Fig. 50.11
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• The angle of the earth’s axis is responsible for seasonal
variations on the earth.
Fig. 50.12
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• The tropics that lie between 23.5° north latitude and
23.5° south latitude experience the greatest input and
least seasonal variation in solar radiation of any
region on earth.
• Intense solar radiation near the equator initiates a
global circulation of air, creating precipitation and
winds.
• This creates prevailing air currents.
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Fig. 50.13
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• Local and seasonal effects on climate.
• Bodies of water and topographic features such as
mountain ranges can affect local climates.
• Ocean currents can influence climate in coastal areas.
• Mountains affect rainfall greatly.
Fig. 50.14
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• Ponds and lakes are sensitive to seasonal temperature
change.
• Turnover brings oxygenated water from the surface of
lakes to the bottom and nutrient-rich water to the top.
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Fig. 50.15
• Microclimate.
• Climate can vary on a small scale also.
• Scientists can refer to microclimate on a forest floor
or under a rock.
• Long-term climate change.
• Climate changes can have long-term effects on the
biosphere.
• Global warming may affect distribution of
organisms.
• The ice ages affected distribution in the past.
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• The range of the American Beech can be predicted
under 2 climate-change scenarios.
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Fig. 50.16