Climate in the United States

1
Climate in the United States

• P. Lobosco

2
Climate Regions of U.S.

• Mediterranean
• Marine West Coast
• Moist Continental
• Moist Subtropical
• Desert
• Steppe

3
Division of Regions

• The regions are divided based on temperature and
  precipitation.

4
Mediterranean Region

• The coast of California has a Mediterranean
  climate. The name comes from the area around the
  Mediterranean Sea. In the winter cyclones and
  moist maritime polar air masses bring heavy
  precipitation. In the summer there is almost no
  rain. Plant growth consists of shrubs and
  stunted trees. Agriculture is a major occupation.

5
Marine West Coast Region

• The northwestern coast of the United States has a
  marine west coast climate. This is a rainy
  climate because moist air from the Pacific rises
  and releases precipitation onto the Cascade
  Mountains. This produces mild winters and cool
  summers. The type of plant life that is common
  is the forest of needle-leaved trees, cedar,
  spruce, redwood and fir. The economy is based on
  lumber and paper.

6
Moist Continental Region

• The northern part of the United States extending
  from the Midwest to the Atlantic coast of the
  United States. Continental polar air masses
  flowing south produce very cold winters. In the
  summer the area receives warm tropical air
  masses. There are forests of broad-leaved trees
  and needle-leaved trees. Commercial agricultural
  is the main occupation.

7
Moist Subtropical Region

• The southeastern United States has a moist
  subtropical climate. Precipitation is higher and
  summers are hot due to maritime tropical air
  masses flowing inland. In the winter polar air
  masses mix with the maritime tropical and produce
  colder winters. The plant life consists of
  broad-leaved and needle-leaved trees, such as
  oak, chestnut and pine. Citrus fruits are grown
  in this region. Animal life includes herons,
  egrets, alligators, crocodiles and manatees.

8
Desert and Steppe Region

• Located within the western interior of the Untied
  States are two regions that similar climates.
  The desert and steppe regions begin east of the
  western mountain ranges and end in the Great
  Plains. Steppe receives slightly more
  precipitation. Plants, including yucca, and
  sagebrush grow in the desert. The steppe has
  short grass and scattered forests of
  needle-leaved trees. Grazing of livestock occurs
  here.

9
Highlands (Variable) Region

• These regions are located in the mountains. The
  climate varies with latitude and elevation. The
  temperature is low. Precipitation increases with
  elevation. Forestry is the major industry. Fir
  and pine grow here. Mountain areas are used for
  summer grazing for livestock from the Great
  Plains.

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Land Biomes

• Climate determines plant life.
• Plant life determines animal life.
• Scientists classify areas with similar climates,
  plants and animals into divisions called biomes.

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Biomes of the U. S.

• The major land biomes of the United States are
• tundras
• coniferous forests
• deciduous forests
• tropical rain forests
• grasslands
• Deserts.

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Tundras

• Tundras cover about 10 of the Earths surface.
  IN the United States they are only found in
  Alaska. The climate is extremely cold and dry.
  Tundras receive less than 25 centimeters of rain
  and snow. Almost 85 of Alaska if permafrost or
  frozen soil.

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Tundra Plant Life

• Plant life on the tundra consists mainly of
  mosses and grasses. Lichen (algae and fungi
  growing together) cover the rocks and bare
  ground. Tall trees cannot grow.

14
Tundra Animal Life

• Lichens are the main food of caribou.
• Wolves prey on caribou.
• Birds such as ptarmigan and small animals such as
  lemmings inhabit the tundra.
• Arctic terns are seasonal residents.

15
Coniferous Forest

• South of the tundra biomes are the coniferous
  forest biomes. The soil here thaws in the spring
  making the forest floor wet and swampy. A
  coniferous biome is also called a taiga. This
  biome can be found in parts of Alaska as well as
  at the higher elevations of the Rocky Mountains.
  The rainfall is between 50 and 125 centimeters
  and the temperature is cold.

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Coniferous Forest Plant Life

• The trees that live in this biome are
  needle-leaved trees or conifers. Conifers
  produce their seeds in cones. They include firs,
  spruces and pines. Redwoods grow in Washington,
  Oregon and northern California. Southern
  California supports a coniferous biome known as a
  chaparral which consists of shrub like plants.

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Coniferous Forest Animal Life

• Large animals in the coniferous forests include
  wolves, deer, black bears, grizzly bears and
  moose. Smaller animals such as beaver, hares,
  and red squirrels also live here. Crows and
  great-horned owls build nests among the conifers.
  Grouse roost in the branches.

18
Deciduous Forests

• South of the coniferous forest biomes are the
  deciduous forest. Deciduous forests begin at the
  northeastern border between the United States and
  Canada. The summers are warm and the winters
  cold. Rainfall is between 75-150 centimeters a
  year.

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Deciduous Forest Plant Life

• Deciduous trees shed their leaves in the autumn.
  Oak, birch, maple, hickory and beech are the most
  common varieties found in the United States. In
  the spring wildflowers and ferns cover the forest
  floor.

20
Deciduous Forest Animal Life

• Many different animals make their home in
  deciduous forests. Thrushes, woodpeckers,
  cardinals and blue jays are birds that live in
  these forests. Snails, worms, snakes and
  salamanders live on the forest floor. Small
  mammals, such as squirrels and raccoons live in
  the branches of the trees.

21
Tropical Rain Forest

• In the United States, tropical rain forests are
  only found in Hawaii. Rainforests receive at
  lest 200 centimeters of rainfall a year.
  Temperatures are warm year round.

22
Tropical Rain Forest Plant Life

• Rain forests have more varieties of plant life
  than any other biome. Trees may grow to a height
  of 35 meters or more. High above the forest
  floor, the tops of trees met to form a canopy.
  The canopy is so thick that sunlight may not
  reach the forest floor for 10 minutes. Most
  plant grow in the canopy. Orchids and ferns grow
  on the branches of trees. Woody vines hang from
  trees.

23
Tropical Animal Life

• Animal life in the rain forest is rich and
  varied. Some rain forest animals spend their
  entire life in the trees and never touch the
  forest floor. Parrots, toucans and hundreds of
  other birds live in the trees. Insects, tree
  frogs and snakes crawl on the trunks and branches
  of trees. Bats hunt at night.

24
Grasslands

• The grassland biomes receive between 25 and 75
  centimeters of precipitation a year. The
  grasslands of the Midwestern plains have hot
  summers and cold winters.

25
Grasslands Plant Life

• Grasses make up the main group of plants in this
  biome. There are few trees due to low rainfall.
  Fires, which occur often, prevent widespread tree
  growth. Today, most of the original grasslands
  have been replaced with pastures and farms.
  Wheat, corn and other grains are farmed on the
  Midwestern plains.

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Grasslands Animal Life

• Gophers, prairie dogs, and other small animals
  live on the grasslands. Black birds, prairie
  chickens and meadow larks are some of the birds
  that feed on the grasshoppers, locusts and other
  insects. Bison and elk, large plant eaters,
  were once common. They were hunted by wolves and
  cougars. Since farms have replaced most of the
  grasslands, large animal live only in protected
  areas.

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Deserts
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Deserts

• Deserts receive less than 25 centimeters of rain
  a year. Desert biomes in the United States are
  located in the Southwest. Although deserts can
  be hot or cold, the deserts of the southwestern
  Untied States are hot.

29
Desert Plant Life

• Plants that exist in the desert have adapted to a
  lack of rainfall. The fleshy stem of cacti help
  then to store water. Some can store up to a ton
  of water. Most flowering plants in the desert
  produce seeds and die within a few weeks due to
  lack of rainfall.

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Desert Animal Life

• Like the plants, animals must be able to survive
  with very little rainfall. Plant eating animals
  such as jack rabbits and kangaroo rats obtain
  most of their water from the plants they eat.
  Meat-eating animals, such as cougars, obtain most
  of their water by eating the plant eaters. Most
  desert animals hide from the hot sun during the
  day and come out to eat only at night, when
  temperatures are cooler.