Chapter 7 Review
Climate and Biodiversity
By: Zachary Cox
Ch. 7 Contents
7-1: What Factors Influence Climate
7-2: How does Climate Affect the Nature and Location of Biomes
7-3: How Have We Affected the World’s Terrestrial Ecosystem
3 Big Ideas
7-1: What Factors Influence Climate
The Earth has many climates
Greenhouse Gases warm the lower Atmosphere
Earth’s Surface Features Affect Local Climates
7-1: The Earth has many Climates
•
Weather – A set of physical conditions of the lower atmosphere such as
temperature, precipitation, humidity, wind speed, cloud cover, and other
factors in a given area over a period of hours or days
•
Climate – Which is an area’s general pattern of atmospheric conditions over
periods of at least three decades and up to thousands of years
•
3 Major Factors that determine how air circulates
– Uneven heating of the earth’s surface by the sun
– Rotation of the Earth on its Axis
– Properties of water, air, and land
• Ocean Currents – Prevailing winds blowing over the oceans produce mass
movements of surface water
7-1: Greenhouse Gases Warm the
Lower Atmosphere
• Greenhouse Gases - allow mostly visible light and some
infrared radiation and ultraviolet (UV) radiation from the sun
to pass through the atmosphere.
• Examples of Greenhouse Gases are:
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Water Vapor
Carbon Dioxide
Methane
Nitrous Oxide
• Natural Greenhouse Effect - natural warming effect of the
troposphere
7-1: Earth’s Surface Features Affect
Local Climates
• Heat is absorbed and released more slowly by water than by
land
• Rain Shadow Effect - Semiarid or arid conditions on the
leeward side of a high mountain
• Cities create distinct microclimates. Building materials absorb
heat and buildings block wind flow.
• This causes cities to have higher temperatures, and lower
wind speeds than the surrounding countryside
7-2: How does climate affect the
nature and location of biomes
Climate Helps to determine where organisms can live
There are 3 Major types of Deserts
There are 3 major types of Grasslands
There are 3 major types of Forests
Mountains play important Ecological Roles
7-2: Climate Helps to determine where
organisms can live
• Biomes - Large terrestrial regions, each characterized by
certain types of climate and dominant plant life
• Ex. Are:
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Desert
Polar Ice
Artic Tundra
Temperate Rainforest
• Differences in climate can lead to the formation of tropical,
temperate, and polar deserts, grasslands, and forests
7-2: There are 3 Major types of
Deserts
• Deserts:
– Annual precipitation is low and often scattered unevenly throughout the
year
– Hot during the day and cold during the night
– Low vegetation
• Tropical deserts (i.e. Sahara) are hot and dry most of the year
• In Temperate deserts (i.e. Sonoran), daytime temperatures are high
in summer and low in winter and there is more precipitation than in
tropical deserts
• In cold deserts (i.e. Gobi), vegetation is sparse, winters are
cold, summers are warm or hot, and precipitation is low
7-2: There are 3 major types of
Grasslands
• Grasslands occur mostly in the interiors of continents in areas that are too
moist for deserts to form and too dry for forests to grow
• Permafrost - Underground soil in which captured water stays frozen for
more than 2 consecutive years
• Cold grasslands, or arctic tundra (Russian for “marshy plain”), lie south of
the arctic polar ice cap. Winters are long with short days, and scant
precipitation falls mostly as snow
• In a temperate grassland, winters can be bitterly cold, summers are hot
and dry, and annual precipitation is fairly sparse and falls unevenly
throughout the year
• Tropical grasslands usually has warm temperatures year-round and
alternating dry and wet seasons
7-2: There are 3 major types of Forests
• Forests are lands dominated by trees
• Tropical rain forests are found near the equator, where hot, moistureladen air rises and dumps its moisture
• Temperate deciduous forests grow in areas with moderate average
temperatures that change significantly with the seasons. Temperate
Forests have long, warm summers, cold but not too severe winters, and
abundant precipitation, often spread fairly evenly throughout the year
• Evergreen Coniferous Forests are found just south of the arctic tundra in
northern regions across North America, Asia, and Europe and above
certain altitudes in the Sierra Nevada and Rocky Mountain ranges of the
United States
• Temperate rain forests are found in scattered coastal temperate areas
with ample rainfall or moisture from dense ocean fogs
7-2: Mountains play important
Ecological Roles
• Mountains are places where dramatic changes in altitude,
slope, climate, soil, and vegetation take place over a very
short distance
• Mountains contain the majority of the world’s forests, which
are habitats for much of the planet’s terrestrial biodiversity
• Mountains also store water. In the winter, it stores the snow
and ice. In the summer, the water is released into the streams
7-3: How Have We Affected the
World’s Terrestrial Ecosystems
Humans Have Disturbed Most of the Earths Land
7-3: Humans Have Disturbed Most of
the Earths Land
• About 62% of the world’s major terrestrial
ecosystems are being degraded or used
unsustainably
• If we increase the stresses on some of these
biomes, then we would have a massive loss of
biodiversity.
• It would also reduce the vegetation needed to
remove some of the excess carbon dioxide that
we add to the atmosphere
• This would release more CO2 into the
atmosphere
3 Big Ideas
• Differences in climate, based mostly on long-term
differences in average temperature and
precipitation, largely determine the types and
locations of the earth’s deserts, grasslands, and
forests
• The earth’s terrestrial systems provide important
ecological and economic services.
• Human activities are degrading and disrupting
many of the ecological and economic services
provided by the earth’s terrestrial ecosystems