Unit 15b Biosphere climate and biomes

15.1 Life in the Earth System

KEY CONCEPT The biosphere is one of Earth’s four interconnected systems.

15.1 Life in the Earth System

The biosphere is the portion of Earth that is inhabited by life. What kinds of things would it include?

• The biosphere includes all ecosystems.– one of Earth’s systems

– includes the biota, all the living things in the biosphere

15.1 Life in the Earth System

• There are three other Earth systems.

– Hydrosphere—water, ice, and water vapor (Oceans, Rivers, Lakes, and groundwater)

– Atmosphere—air blanketing Earth’s solid and liquid surface

– Geosphere—geologic features above and below Earth’s surface

– Life has been found in all of these systems and virtually everywhere we have looked

15.2 Climate

KEY CONCEPT Climate is a key abiotic factor that affects the biosphere. How?

15.2 Climate

Climate is the prevailing weather of a region.

• Climate is the long-term pattern of weather conditions. What conditions would be included?– average temperature– precipitation– relative humidity

• Key factors shape an area’s climate.– temperature– sunlight– water– wind

15.2 Climate

• A microclimate is the climate of a small specific place within a larger area.

15.2 Climate

Earth has three main climate zones.

• The three main zones are the polar, tropical, and temperate climates. Which do we live in?– polar climate: the far northern

and southern regions ofEarth

– tropical zone: surrounds the equator

– temperate zone: the wide area in betweenthe polar and tropical zones

15.2 Climate

• The angle of the Sun’s rays determine an area’s climate.

temperatetemperate

polarpolar

tropicaltropical

temperatetemperate

polarpolar

90 N

15.2 Climate

• Earth’s tilt on its axis results in seasonal change.

• Solar heating causes movements in both water and air. Why?– wind– ocean currents

• Earth’s rotation also has effects on the winds and currents. How?

• The uneven heating of the Earth is the ultimate cause of all weather. Why?

15.2 Climate

• Mountains have an effect on climate. How?

western slope eastern slope

– Precipitation occurs on the side of the mountain facing the wind. Why?

– On the downwind side, drier and cooler air produce a rain shadow. Why?

15.3 Biomes

KEY CONCEPT Biomes are land-based, global communities of organisms.

15.3 Biomes

Earth has six major biomes.• A biome is a major community of organisms.

15.3 Biomes

• Tropical rain forest biomes produce lush forests. Why?

– warm temperature– abundant

precipitation all year

Source: World Meteorological Organization

15.3 Biomes

• Grassland biomes are where the primary plant life is grass.

Rapid City, South Dakota

Source: National Oceanic Atmospheric Administration

15.3 Biomes

– Temperate grasslands are dry and warm during the summer; cold in winter with most precipitation falls as snow.

• Grassland biomes are where the primary plant life is grass.

– Tropical grasslands are warm throughout the year, with definite dry and rainy seasons.

15.3 Biomes

• Desert biomes are characterized by a very arid climate. Why?– very low amount of

precipitation– four types: hot, semi-

arid, coastal, and cold

Tucson, Arizona

Source: National Oceanic Atmospheric Administration

15.3 Biomes

• Temperate forest biomes include deciduous forests and rain forests.– Temperate deciduous forests have hot summers and

cold winters.– Deciduous trees are the dominant plant species.

Source: National Oceanic Atmospheric Administration

Burlington, Vermont

15.3 Biomes

– Deciduous trees are the dominant plant species.– The temperate rain forests have a long wet season and

relatively dry summer.

• Temperate forest biomes include deciduous forests and rain forests.– Temperate deciduous forests have hot summers and

cold winters.

– Ferns and moss cover the forest floor. 

15.3 Biomes

• The taiga biome is located in cooler northern climates.– boreal forest– long winters and short

summers– small amount of

precipitationSource: Environment Canada

Banff, Canada

15.3 Biomes

• The tundra biome is found in the far northern latitudes with long winters.– winter lasts 10 months– limited precipitation– permafrost

Barrow, Alaska

Source: National Oceanic Atmospheric Administration

15.3 Biomes

• Minor biomes, such as chaparral, occur globally on a smaller scale.

15.3 Biomes

Polar ice caps and mountains are not considered biomes.• Polar ice caps have no soil, therefore no plant community. • The climate and organisms found on mountains change as

the elevation changes.

15.3 Biomes

1. Which type of growth occurs when a population has unlimited resources and no predators?

• A. logistic growth • B. exponential growth • C. S-shaped growth • D. population crash

15.3 Biomes

Which type of growth occurs when a population has unlimited resources and no predators?

• A. logistic growth • B. exponential growth • C. S-shaped growth • D. population crash• Correct Answer = B

Which of the following can cause a population crash? • A. a rise in the carrying capacity for a population • B. a rise in the emigration rate • C. a drop in the immigration rate • D. a drop in the carrying capacity for a population

15.3 Biomes

Which type of growth occurs when a population has unlimited resources and no predators?

• A. logistic growth • B. exponential growth • C. S-shaped growth • D. population crash• Correct Answer = B

Which of the following can cause a population crash? • A. a rise in the carrying capacity for a population • B. a rise in the emigration rate • C. a drop in the immigration rate • D. a drop in the carrying capacity for a population• Correct Answer = D

15.3 Biomes

Review

• The biosphere is the part of Earth that contains all living things and includes all the ecosystems.

• Climate is the prevailing weather over an area• The uneven heating of the Earth due to its shape, tilt and

rotation determines weather.• The Earth has six major biomes:

– Tropical Rainforest– Grasslands– Desert– Temperate forest– Taiga– Tundra