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Weather, Climate and Biomes
WEATHER & CLIMATE
www.kowoma.de/en/gps
Weather (troposphere) short term occurrences at a particular place and timeClimate (troposphere) a region’s long term, general pattern of weather conditions
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)
ABIOTIC FACTORS OF WEATHER
1. Temperature2. Precipitation (rain, snow, sleet,
hail)3. Humidity4. Pressure5. Cloud Cover6. UV Radiation7. WindWarm 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 PatternsRAIN SHADOW EFFECT!
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.
Windward Side of Mountain – high precipitation & forested area
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 Climatograp
h
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
Soil is old, thin, acidic; nutrient poor because most nutrients are in the biomass
Distinct strata (zones) such as canopy, emergent, understory, shrub, & forest floor, provide habitat space for the abundant life
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 desertbiomes 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 DesertTropical 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 semi-
summer 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