Weather, Climate and Biomes
WEATHER & CLIMATE
Weather (troposphere) short
term occurrences at a
particular place and time
www.kowoma.de/en/gps
 Troposphere = 78% N2; 21% O2; 1% Argon, CO2 and trace gases
 99% of the mass of the atmosphere is in the troposphere + stratosphere
 Stratosphere = contains atmospheric ozone (absorbs UV radiation)
Climate (troposphere) a
region’s long term, general
pattern of weather
conditions
ABIOTIC FACTORS OF WEATHER
1.
2.
3.
4.
5.
6.
7.
Temperature
Precipitation (rain, snow, sleet, hail)
Humidity
Pressure
Cloud Cover
UV Radiation
Wind
Warm Fronts – low pressure; less dense; raises over air masses (cloudy skies & drizzle)
Cold Fronts – high pressure; dense; pushes in under warm air (thunderstorms & then clear
skies & nice weather
Topographic Features Influence Weather Patterns
RAIN SHADOW EFFECT!
Prevailing winds pick up
moisture from an ocean.
Windward Side of Mountain – high
precipitation & forested area
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.
Leeward Side of Mountain – low precipitation
& arid to semi-arid conditions (deserts)
LOCATION, LOCATION, LOCATION
Global Air Circulation
and Biomes
Tundra
Deciduous Forest
Savanna
Taiga
Chaparral
Rainforest
Grasslands
Desert
Alpine
Desert-scrub
Biomes
Climatograph
Mountains
• Steep or high lands which cover about ¼ of the
earth’s land surface
• They are not a biome but they have dramatic
impacts on our ecosystems
– They contain the majority of the world’s forests
– Provide a habitat for endemic species that are found no
where else in the world
• Serve as a sanctuary for animal species driven to migrate
from lowland areas to higher altitudes
– Help to regulate earth’s climate due to snow and ice
reflecting solar radiation back into space
– Melting mountain-top snowpack provide surface water
in streams for use by animals
Human Impacts
•
•
•
•
•
•
Agriculture
Timber extraction
Mineral extraction
Increasing tourism
Urban air pollution
Increased ultraviolet radiation from ozone
depletion
• Soil damage from off-road vehicles
Types of Forest
Tropical Rain Forests
Temperate Deciduous Forests
Taigas (Boreal Forests)
• Dominated by trees
• Areas of high productivity and biodiversity
Tropical Rain Forest
• Typically found along
the equator
• Also found 30oN to 30oS
from the equator
• Brazil, Central America,
Indonesia, Central
Africa
• 20oC – 30oC
• >200 cm rainfall
Fig. 7-15a, p. 154
Characteristics
• Year round consistently warm temperatures,
high humidity, and heavy rainfall
• Dominated by broadleaf evergreen plants
• High primary productivity and biodiversity
• Importance:
–
–
–
–
Recycling of CO2
Release of O2
Biodiversity
Medicinal Purposes
Distinct strata (zones) such as canopy, emergent, understory,
shrub, & forest floor, provide habitat space for the abundant
life
Soil is old, thin, acidic; nutrient poor because most nutrients
are in the biomass
Plant Adaptations
• Have thin, smooth bark
• Climbing vine and other plants grow on
rainforest trees, climbing into the canopy
so its leaves get more sunlight
• The leaves are big, thick and waxy, and
have 'drip tips' to let the rain drain off
quickly
• Some tropical rainforest plants are
carnivorous, or meat-eating
• Thousands of flowering plants grow onto
trees so they get sunshine. Their roots are
not in soil, and the plants get their food
from air and water.
Animal
Adaptations
• They are adapted to eating a specific plant or animal that
few others eat.
• Since the rain forest has many trees, animals are able to
climb and forage for food in trees (monkeys and sloths)
• They are able to swim and cope with a lot of rainfall
(caimans, turtles and snakes)
• Some are nocturnal to avoid the high temperatures of the
day and the competition from diurnal animals (bats)
• Some have developed camouflaging mechanisms
Major Human Interferences
•
•
•
•
Agriculture
Timber harvest
Livestock grazing
Some mineral mining
Temperate Deciduous Forests
• Found between 30o and
60o north and south
latitudes
• Eastern United States,
most of Europe
• 0oC – 20oC mild climate
• 75 to 150 cm rainfall
Fig. 7-15b, p. 154
Characteristics
• Moderate temperatures that fluctuate with
seasons, four distinct season
• Five layers to the forest: Tree stratum (oak,
beech, maple); Sapling Zone; Shrub
(rohodendrons, azalea); Herbal; Ground
(moss, lichen)
• Trees go dormant in the winter by dropping
their leaves in the fall
• Soil: high nutrients due to deciduous trees,
lots of humus and leaf litter
Plant Adaptations
• SUMMER: their broad green leaves to
capture sunlight needed to make food
through photosynthesis.
• As temperatures drop, the tree cuts off
the supply of water to the leaves and
seals off the area between the leaf stem
and the tree trunk.
• With limited sunlight and water, they
change colors
• WINTER: they loose the leaves since
they cannot protect them.
– Losing their leaves helps trees to conserve
water loss through transpiration.
Animal Characteristics
• Organisms are mostly dark in
coloration to blend in with the
environment
• Animals hibernate
• Some migrate to warmer climates
during the winter
• Some store food for the winter
Major Human Interference
•
•
•
•
Logging
Agriculture
Tree farms
Urbanization
Taigas (Boreal Forests)
• Found just south of
the arctic tundra in
northern regions of
North America
(Canada), Asia and
Europe
• -5oC – 15oC
• less than 50 to 150
cm rainfall
Fig. 7-15c, p. 154
Characteristics
•
•
•
•
Taiga is the largest biome on earth
Winters are long, dry, and extremely cold
Plant diversity is low
Acidic soils, lots of litter but slow
composition
Plant Adaptations
• Few species of conifers
– Pine
– Hemlock
– Cedar
– Spruce
• Shed snow easily, and retain their
needles through the winter.
• The needles are adapted, with
thick waxy coatings and small
surface area, to resist cold
conditions and minimize water loss
Animal Adaptations
• large paws (for running over the snow)
• white fur (to blend in)
• may burrow beneath the snow and
forage for their food in tunnels on and in
the forest floor; they are insulated from
the worst cold of winter by the snow.
• Others hibernate during the winter.
• Some bird species deal with the cold by
migrating south during the cold winter
and returning in the spring
Major Human Interference
•
•
•
•
Logging
Mining
Fur trade
Dams
Types of Grasslands
Tropical Grassland (Savannas)
Temperate Grassland (tall and short grass prairies)
Cold Grasslands (artic tundra)
• Exists in areas where there is too much moisture for
desert
biomes and too little moisture for forest biomes
• Regulated by seasonal drought, occasional fires, and the
grazing of herbivores
• Found in the interior of continents
Tropical Grassland (Savannas)
• Largely found in
Eastern Africa
• Also parts of South
America and Australia
• 8oC – 20oC
• 50 – 150 cm rainfall
Fig. 7-12a, p. 151
Characteristics
• Warm temperatures and alternating warm and dry
seasons (will experience several months of little/no rain
fall)
• Large grazing herbivores such as gazelles, zebras,
wildebeests
• Plants have deep roots to utilize groundwater supplies
• Soil: low in minerals, easily leached, may have high
levels of aluminum
Major Human Interferences
• Livestock grazing
• Agriculture
• Poaching
Temperate Grasslands
• Location:
– Prairies: mid-western and
western United States and
Canada
– Pampas: South America
– Steppes: Russia
– Veld: South Africa
• -5oC – 10oC
• 25 – 100 cm rainfall
Fig. 7-12b, p. 151
Characteristics
• Rainfall determines whether it is a tall-grass or a
short-grass prairie (tall-grass prairies receive
almost three times as much rain as short-grass)
• Winters are cold, summers are hot and dry
• As grasses die and decompose annually, large
amounts of organic matter accumulates in the
soil, making this area high productive for crops
• High winds and rapid evaporation promotes fires
in the summer and fall that eliminates other
competing species
Major Human Interferences
• Agriculture
• Livestock grazing if too dry for crops
Cold Grasslands (Artic Tundra)
• Located between 55°
and 70° Northern
Latitude.
• In other words, they
extend mostly in the
top portion of the
Northern Hemisphere.
• -20oC to 10oC
• <10 cm rainfall
Fig. 7-12c, p. 151
Characteristics
• Frigid, treeless plains that are covered with
snow and ice much of the year
• Extreme cold forms permafrost –
underground soil in which captured water
stays frozen for more than two consecutive
years
• Low biodiversity
• Short season of growth and reproduction
• Soils thin; soils very young; nutrient poor –
since there is little organic litter
Major Human Interferences
• Too cold for much human activity
• Oil/natural gas drilling and associated
transport issues
• Global warming which is melting
permafrost in summer
Grassland Plant Adaptations
• During dry periods grasses can become dormant, leaving
only dry stems and seed heads standing above the roots.
When rain falls, new shoots come up from the roots again.
• Some grasses are annuals, and survive the winters as seeds
• Other species are perennials, and sprout again each year
from a well-developed network of roots.
• Another adaptive characteristic of grasses is that they grow
up from where the stems join the roots.
– This allows animals to eat grass without slowing its growth, and
people to mow lawns without killing the grass
Grassland Animal Adaptations
• Migration is one of the most prominent adaptations.
– Several animal species which inhabit the Savannah migrate
thousands of miles in search of food and water during a particular
time of the year.
• have broad and flat-topped teeth which makes it easy for
them to feed on grass.
• The small animals seek shelter by burrowing in the ground.
– the front feet of these animals are armed with sharp claws
• Adapted to withstand the extreme climatic conditions,
characterized by hot summers and cold winters
• Specially developed digestive system for herbivores
• The ability of these animals to camouflage
Types of Desert
Tropical Deserts
Temperate Deserts
Cold Deserts
• Occurs in continent interiors where little precipitation is often
distributed unevenly throughout the year; < 30 cm
• Experience intense heat and evaporation during the day and
cooler nights due to rapid heat loss from the little vegetation
available to help radiate the heat more slowly
• Temperature depends on location, deserts usually at 30oN or 30oS
of equator or interior of continents due to rain shadow effect; -5
to 30o C
• Soil
Tropical Deserts
• Cover much of northern
Africa (the Sahara)
• Parts of the Middle East
(Saudi Arabia)
Fig. 7-11a, p. 149
Characteristics
• Surface areas have little vegetation and are
dominated by rocks and sand that are
often blown about by frequent windstorms
• Extremely high daytime temperatures
Temperate Deserts
• Found in southwestern
United States (Mojave
and Sonoran deserts)
Fig. 7-11b, p. 149
Characteristics
• Receive more precipitation than tropical
deserts
• Characterized by patchy drought-resistant
plants
• Have high daytime and low nighttime
temperatures
Cold Deserts
• Areas of the United
States known as the
Great Basin (Idaho,
Utah)
• Gobi desert in northern
China and southern
Mongolia
Fig. 7-11c, p. 149
Characteristics
• Vegetation is very sparse
• Winters are extremely cold
Desert Plant Adaptations
• Reduction of leaves, often into spines. Reduces surface
area for water loss.
• Development of the stem as a photosynthetic structure
• Water storage in the stem
• Development of defense structures. (spines and chemical
defenses).
• Coating the plant with a thick waxy cuticle to prevent
water loss.
• A dense coating of hairs, decreases evaporation.
• Extensive underground root systems. These roots can
grow straight down to groundwater, or spread out to take
advantage of short, intermittent rains.
Desert Animal Adaptations
• A nocturnal lifestyle, which keeps them out of
the heat of day
• Living in burrows, which are cooler and more
humid.
• Slender bodies with long limbs - better for
shedding heat.
• Adaptations for reducing water loss specialized snouts, waxy body coatings, efficient
kidneys, etc.
• Some get all their water from the food they eat.
• Eyes protected from the sun. Long eyelashes or
deep-set eyes
Major Human Interference
•
•
•
•
•
Off-road vehicles
Overgrazing
Urbanization
Oil drilling
Mining
The Chaparral (Temperate Shrubland)
• Considered to be a minor biome
• Found along coastal areas
• Between 30 and 40 degrees
north of the equator
– Southern California
– Mediterranean Sea
• between 30 and 40 degrees
south of the equator
– Central Chile
– South Africa
– Australia
•0oC – 38oC
•40 – 60 cm rainfall
Fig. 7-14, p. 152
Characteristics
•
•
•
•
Characterized by scrub vegetation
3 seasons: fall, spring and drought
Mild Winters; HOT Summers
Soil: shallow, rocky, nutrient poor
Chaparral Plant Adaptations
• Chaparral plants employ four different
strategies in response to drought.
– Avoiders (avoid drought with long roots and
hard/thick leaves)
– Persisters (tolerate drought by physiological
adaptations and movements)
– Retreaters (annuals or underground storage
organs)
– Chameleons (evade drought by being semisummer deciduous)
Chaparral Animal Adaptations
• Animals do not require much water.
• Nocturnal and are usually small.
• Have adapted to this sparse and rough terrain by
becoming agile climbers, foraging over larger areas
and varying their diet to include the often scrubby
brush lands.
Major Human Interference
• Urbanization
• Fires lead to flooding