Climate and Terrestrial Biodiversity Chapter 7

Dust Blown from West Africa to the Amazonian Rain Forests

7-1 What Factors Influence Climate? Concept 7-1 An area's climate is determined mostly by solar radiation, the earth’s rotation, global patterns of air and water movement, gases in the atmosphere, and the earth’s surface features.

The Earth Has Many Different Climates (1) Weather Climate Air circulation in lower atmosphere due to Uneven heating of the earth’s surface by the sun Rotation of the earth on its axis Properties of air, water, and land

The Earth Has Many Different Climates (2) Currents Prevailing winds Earth’s rotation Redistribution of heat from the sun Link between air circulation, ocean currents, and biomes

Natural Capital: Generalized Map of the Earth’s Current Climate Zones

Global Air Circulation

Energy Transfer by Convection in the Atmosphere

Global Air Circulation, Ocean Currents, and Biomes

Warm, less salty, shallow current Figure 7.5 Connected deep and shallow ocean currents. A connected loop of shallow and deep ocean currents transports warm and cool water to various parts of the earth. This loop, which rises in some areas and falls in others, results when ocean water in the North Atlantic near Iceland is dense enough (because of its salt content and cold temperature) to sink to the ocean bottom, flow southward, and then move eastward to well up in the warmer Pacific. A shallower return current aided by winds then brings warmer, less salty—and thus less dense—water to the Atlantic. This water can cool and sink to begin this extremely slow cycle again. Question: How do you think this loop affects the climates of the coastal areas around it? Cold, salty, deep current Fig. 7-5, p. 143

Greenhouse Gases Warm the Lower Atmosphere CO2 CH4 N2O Greenhouse effect Human-enhanced global warming

Flow of Energy to and from the Earth

The Earth’s Surface Features Affect Local Climates Heat absorption by land and water Effect of Mountains Rain shadow effect Cities Microclimates

Rain Shadow Effect

7-2 How Does Climate Affect the Nature and Locations of Biomes? Concept 7-2 Differences in average annual precipitation and temperature lead to the formation of tropical, temperate, and cold deserts, grasslands, and forests, and largely determine their locations.

Climate Affects Where Organisms Can Live Major biomes Latitude and elevation Annual precipitation Temperature

The Earth’s Major Biomes

Generalized Effects of Elevation and Latitude on Climate and Biomes

Figure 7.11 Climate graphs showing typical variations in annual temperature (red) and precipitation (blue) in tropical, temperate, and cold deserts. Top photo: a popular (but destructive) SUV rodeo in United Arab Emirates (tropical desert). Center photo: saguaro cactus in the U.S. state of Arizona (temperate desert). Bottom photo: a Bactrian camel in Mongolia’s Gobi Desert (cold desert). Question: What month of the year has the highest temperature and the lowest rainfall for each of the three types of deserts? Stepped Art Fig. 7-11, p. 149

Figure 7.12 Climate graphs showing typical variations in annual temperature (red) and precipitation (blue) in tropical, temperate, and cold (arctic tundra) grassland. Top photo: wildebeests grazing on a savanna in Maasai Mara National Park in Kenya, Africa (tropical grassland). Center photo: wildflowers in bloom on a prairie near East Glacier Park in the U.S. state of Montana (temperate grassland). Bottom photo: arctic tundra (cold grassland) in autumn in front of the Alaska Range, Alaska (USA). Question: What month of the year has the highest temperature and the lowest rainfall for each of the three types of grassland? Stepped Art Fig. 7-12, p. 151

Monoculture Crop Replacing Biologically Diverse Temperate Grassland

Chaparral Vegetation in California, U.S.

Santa Monica Mountains, CA

Figure 7.15 Climate graphs showing typical variations in annual temperature (red) and precipitation (blue) in tropical, temperate, and cold (northern coniferous and boreal) forests. Top photo: the closed canopy of a tropical rain forest in the western Congo Basin of Gabon, Africa. Middle photo: a temperate deciduous forest in the U.S. state of Rhode Island during the fall. (Photo 4 in the Detailed Contents shows this same area of forest during winter.) Bottom photo: a northern coniferous forest in the Malheur National Forest and Strawberry Mountain Wilderness in the U.S. state of Oregon. Question: What month of the year has the highest temperature and the lowest rainfall for each of the three types of forest? Stepped Art Fig. 7-15, p. 154

Black-crowned antpitta 45 Harpy eagle Emergent layer 40 35 Toco toucan Canopy 30 25 Height (meters) 20 Under story Wooly opossum 15 Figure 7.17 Stratification of specialized plant and animal niches in a tropical rain forest. Filling such specialized niches enables species to avoid or minimize competition for resources and results in the coexistence of a great variety of species. 10 Brazilian tapir Shrub layer 5 Black-crowned antpitta Ground layer Fig. 7-17, p. 156

Temperate Rain Forest in Washington State, U.S.

Mountains Play Important Ecological Roles Majority of the world’s forests Habitats for endemic species Help regulate the earth’s climate Can affect sea levels Major storehouses of water Role in hydrologic cycle

Mount Rainier National Park in Washington State, U.S.

More Mountains!

7-3 How Have We Affected the Word’s Terrestrial Ecosystems? Concept 7-3 In many areas, human activities are impairing ecological and economic services provided by the earth’s deserts, grasslands, forests, and mountains.

NATURAL CAPITAL DEGRADATION Major Human Impacts on Terrestrial Ecosystems Deserts Grasslands Forests Mountains Large desert cities Conversion to cropland Clearing for agriculture, livestock grazing, timber, and urban development Agriculture Figure 7.20 Major human impacts on the world’s deserts, grasslands, forests, and mountains. Question: Which two of the impacts on each of these biomes do you think are the most harmful? Timber extraction Soil destruction by off-road vehicles Release of CO2 to atmosphere from burning grassland Mineral extraction Hydroelectric dams and reservoirs Soil salinization from irrigation Conversion of diverse forests to tree plantations Increasing tourism Overgrazing by livestock Urban air pollution Depletion of groundwater Increased ultraviolet radiation from ozone depletion Damage from off-road vehicles Oil production and off-road vehicles in arctic tundra Land disturbance and pollution from mineral extraction Pollution of forest streams Soil damage from off-road vehicles Fig. 7-20, p. 158