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Terrestrial Biomes
Objective:
CLIMATE: a brief review
 Weather
is a local area’s short-term physical
conditions such as temperature and
precipitation.
 Climate is a region’s average weather
conditions over a long time.

Latitude and elevation help determine climate.
• Latitude: distance from the equator
• Longitude: east to west distance from meridian
• Elevation: distance above sea level
Earth’s Current Climate Zones
Figure 5-2
Distributing Heat
 Global
air
circulation is
affected by the
uneven heating of
the earth’s surface
by solar energy

seasonal changes
in temperature and
precipitation
Figure 5-3
Spring
(sun aims directly
at equator)
Winter
(northern hemisphere 23.5 °
tilts away from sun)
Solar
radiation
Summer
(northern hemisphere
tilts toward sun)
Fall
(sun aims directly at equator)
Fig. 5-3, p. 102
Coriolis Effect
• Definition: the
acceleration of an
object based on
rotation
• Counterclockwise
in the northern
hemisphere
• Clockwise in the
southern
hemisphere
Coriolis Effect
 Global
air
circulation is
affected by the
rotation of the
earth on its axis
Figure 5-4
Convection Currents
 Global
air
circulation is
affected by the
properties of air
water, and land.
Figure 5-5
LOW
PRESSURE
Cool, dry
air
HIGH
PRESSURE
Heat released
radiates to space Condensation
Falls, is compressed,
warms
and
precipitation
Rises, expands, cools
Warm,
dry air
Hot, wet
air
Flows toward low pressure,
picks up moisture and heat
HIGH
Moist surface warmed
PRESSURE
by sun
LOW
PRESSURE
Fig. 5-5, p. 103
Convection Cells
 Heat
and moisture
are distributed over
the earth’s surface
by vertical currents,
which form six giant
convection cells at
different latitudes.
 “Warm air rises, cold
air sinks”
Figure 5-6
Cell 3 North
Cold,
dry air
falls
Moist air rises — rain
Polar cap
Arctic tundra
Evergreen
60°coniferous forest
Temperate deciduous
forest and grassland
30°Tropical Desert
Cell 2 North
Cool, dry
air falls
Cell 1 North
deciduous
forest
0°Equator
Tropical
deciduous
30°forest
Tropical
rain forest
Desert
Temperate
deciduous
60°forest and
grassland
Cell 1 South
Cool, dry
air falls
Cell 2 South
Polar cap
Cold,
dry air
falls
Moist air rises,
cools, and releases
Moisture as rain
Moist air rises — rain
Cell 3 South
Fig. 5-6, p. 103
Ocean Currents
 Ocean
currents influence climate by
distributing heat from place to place and
mixing and distributing nutrients.
Figure 5-7
Topography and Local Climate:
Land Matters
 Interactions
between land and oceans and
disruptions of airflows by mountains and
cities affect local climates.
Figure 5-8
Windward: the side from which the wind is blowing
Prevailing winds
pick up moisture
from an ocean.
On the windward
side of a mountain range,
air rises, cools, and
releases moisture.
On the leeward side of
the mountain range, air
descends, warms, and
Releases little moisture.
Dry
habitats
Moist
habitats
Leeward: the side sheltered or away from the wind
Fig. 5-8, p. 105
BIOMES:
CLIMATE AND LIFE ON LAND
 Different
climates lead to different
communities of organisms, especially
vegetation.

Biomes – large terrestrial regions characterized
by similar climate, soil, plants, and animals.
BIOMES:
CLIMATE AND LIFE ON LAND
 Biome
type is determined by precipitation,
temperature and soil type
Figure 5-10
BIOMES:
CLIMATE AND LIFE ON LAND
 Parallel
changes occur in vegetation type
when we travel from the equator to the poles
or from lowlands to mountaintops.
Figure 5-11
DESERT BIOMES
 Deserts
are areas where evaporation
exceeds precipitation.
 Deserts have little precipitation and little
vegetation.

Found in tropical, temperate and polar regions.
 Desert
plants have adaptations that help
them stay cool and get enough water.
DESERT BIOMES
 Variations
in
annual
temperature (red)
and precipitation
(blue) in tropical,
temperate and
cold deserts.
Figure 5-12
Box 3: Tropical Desert
Freezing point
Month
Mean monthly precipitation (mm)
Mean monthly temperature (C)
Tropical Desert
Directions: Fill in your Biomes Graphic Organizer as we go!
Fig. 5-12a, p. 109
Box 3: Temperate Desert
Freezing point
Month
Mean monthly precipitation (mm)
Mean monthly temperature (C)
Temperate Desert
Fig. 5-12b, p. 109
Box 3: Polar Desert
Freezing point
Month
Mean monthly precipitation (mm)
Mean monthly temperature (°C)
Polar Desert
Fig. 5-12c, p. 109
DESERT BIOMES
 The
flora and
fauna in desert
ecosystems
adapt to their
environment
through their
behavior and
physiology.
Figure 5-13
GRASSLANDS AND CHAPARRAL
BIOMES
 Variations
in
annual
temperature
(red) and
precipitation
(blue).
Figure 5-14
Box 14: Tropical Savanna
Freezing point
Month
Mean monthly precipitation (mm)
Mean monthly temperature (C)
Tropical grassland (savanna)
Fig. 5-14a, p. 112
Box 10: Temperate Grassland
Freezing point
Month
Mean monthly precipitation (mm)
Mean monthly temperature (C)
Temperate grassland
Fig. 5-14b, p. 112
Box 16: Arctic Tundra
Freezing point
Month
Mean monthly precipitation (mm)
Mean monthly temperature (C)
Polar grassland (arctic tundra)
Fig. 5-14c, p. 112
GRASSLANDS AND CHAPARRAL
BIOMES
 Grasslands
(prairies) occur in areas too moist
for desert and too dry for forests.
 Savannas are tropical grasslands with
scattered tree and herds of hoofed animals.
Temperate Grasslands
 The
cold winters and
hot dry summers
have deep and fertile
soil that make them
ideal for growing
crops and grazing
cattle.
Figure 5-15
Temperate Grasslands
 Temperate
tallgrass prairie
ecosystem in North
America.
Figure 5-16
Arctic Tundra
 Artic
Tundra (polar
grasslands) are
covered with ice and
snow except during
a brief summer.
Figure 5-17
Chaparral
 Chaparral
has a
moderate
climate but its
dense thickets of
spiny shrubs are
subject to
periodic fires.
Figure 5-18
FOREST BIOMES
 Variations
in annual
temperature (red)
and precipitation
(blue) in tropical,
temperate, and
polar forests.
Figure 5-19
Box 13: Tropical Rain Forest
Freezing point
Month
Mean monthly precipitation (mm)
Mean monthly temperature (C)
Tropical rain forest
Fig. 5-19a, p. 116
Box 9: Temperate Deciduous Forest
Freezing point
Month
Mean monthly precipitation (mm)
Mean monthly temperature (C)
Temperate deciduous forest
Fig. 5-19b, p. 116
Box 1: Boreal
Freezing point
Month
Mean monthly precipitation (mm)
Mean monthly temperature (C)
Polar evergreen coniferous forest
(boreal forest, taiga)
Fig. 5-19c, p. 116
FOREST BIOMES
 Forests
have enough precipitation to support
stands of trees and are found in tropical,
temperate, and polar regions.
Tropical Rain Forest
 Tropical
rain forests
have heavy rainfall
and a rich diversity
of species.


Found near the
equator.
Have year-round
uniformity warm
temperatures and
high humidity.
Figure 5-20
Tropical Rain Forest
 Filling
such niches enables species to avoid
or minimize competition and coexist
Figure 5-21
Emergent
layer
Harpy
eagle
Toco
toucan
Canopy
Understory
Woolly
opossum
Shrub
layer
Brazilian
tapir
Black-crowned
antipitta
Ground
layer
Fig. 5-21, p. 118
Temperate Deciduous Forest
 Most
of the trees
survive winter by
dropping their
leaves, which
decay and
produce a nutrientrich soil.
Figure 5-22
Evergreen Coniferous Forests
 Consist
mostly of
cone-bearing
evergreen trees that
keep their needles
year-round to help
the trees survive
long and cold
winters.
Figure 5-23
Temperate Rain Forests
 Coastal
areas support huge cone-bearing
evergreen trees such as redwoods and
Douglas fir in a cool moist environment.
Figure 5-24
MOUNTAIN BIOMES
 High-elevation
islands of
biodiversity
 Often have snowcovered peaks that
reflect solar
radiation and
gradually release
water to lowerelevation streams
and ecosystems.
Figure 5-25
HUMAN IMPACTS ON
TERRESTRIAL BIOMES
 Human
activities have damaged or disturbed
more than half of the world’s terrestrial
ecosystems.
 Humans have had a number of specific
harmful effects on the world’s deserts,
grasslands, forests, and mountains.
Human Impacts: Deserts
 Large
desert cities
 Soil destruction by off-road vehicles
 Soil salinization (saltiness) from irrigation
 Depletion of groundwater
 Land disturbance and pollution from mineral
extraction
Human Impacts: Grasslands
 Conversion
to cropland
 Release of CO2 to the atmosphere from
burning
 Overgrazing by livestock
 Oil production and off-road vehicles in arctic
tundra
Human Effects: Forests
 Clearing
for agriculture, livestock, timber, and
urban development
 Conversion of diverse forests to tree
plantations
 Damage from off-road vehicles
 Pollution of forest streams
Human Impacts: Mountains
 Agriculture
 Timber
extraction
 Mineral extraction
 Hydroelectric dams and reservoirs
 Urban air pollution
 Increased UV rays from ozone depletion
 Soil damage from off-road vehicles