Climate and Terrestrial Biodiversity Chapter 7

What factors influence Climate? How are WEATHER & CLIMATE different?

The Earth Has Many Different Climates Weather – local area’s short-term temperature, precipitation, humidity, wind speed, cloud cover, etc. Measured over hours or days

The Earth Has Many Different Climates Climate – area’s general pattern of atmospheric or weather conditions Measured over long periods of time

The Earth Has Many Different Climates Climate - varies over different parts of the earth Uneven heating of the earth’s surface by the sun Rotation of the earth on its axis Properties of air, water, and land

Solar intensity Amount of sunlight hitting the earth’s surface Varies with latitude

Seasons

Earth’s Atmosphere Tropics – air is warm Equator – 30o N/S

Polar regions – air is cold Earth’s Atmosphere Polar regions – air is cold 60o - 90o N/S

Convection Currents Up-and-down movement of air due to temperature differences

Convection Currents Rule: Hot air rises and cold air sinks. Equator Hot air rises and heads toward the poles

Convection Currents Rule: Hot air rises and cold air sinks. Poles Cold air rushes in to fill the space at the equator

Figure 6.5

Wind Horizontal movement of air

Convection Currents + Earth’s Rotation Equator

Coriolis Effect Earth rotates and causes circulating air to be deflected Causes things thrown in straight line to move to the right or left (depends on hemisphere) If the Earth did not rotate and remained stationary, the atmosphere would circulate between the poles (high pressure areas) and the equator (a low pressure area) in a simple back-and-forth pattern. But because the Earth rotates, circulating air is deflected. Instead of circulating in a straight pattern, the air deflects toward the right in the Northern Hemisphere and toward the left in the Southern Hemisphere, resulting in curved paths. This deflection is called the Coriolis effect. It is named after the French mathematician Gaspard Gustave de Coriolis (1792-1843), who studied the transfer of energy in rotating systems like waterwheels. (Ross, 1995). Continue to 2 3 4  (top) 

Imagine a merry-go-round…

Coriolis Effect Summary Causes moving objects on Earth to follow curved paths Northern Hemisphere – follows a path to the right of its intended target Southern Hemisphere – follows a path to the left of its intended target Acts on all moving objects

Prevailing Winds Major wind patterns on the Earth Direction caused by: Convection currents Earth’s rotation from west to east Air pressure

Global Air Circulation

Wind Belts Trade Winds Historically: Used by ships traveling between Europe and the Americas 5o-30o North and South of the Equator

Wind Belts Doldrums Between 5 degrees North and 5 degrees South latitude Winds are calm

Wind Belts Westerly Winds Remaining air (air that does not descend at 30 degrees North or South latitude) continues toward the poles

Wind Belts Polar Easterlies Cool air sinks and moves towards the equator Air is deflected by Earth’s rotation

Winds Drive Surface Ocean Currents! Global winds drag on the water’s surface Cause water to move and build up in the direction that the wind is blowing

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

Climate and Biomes

Biotic and Abiotic Factors Biological (living) influences on an organism within an ecosystem Predators Prey Abiotic Factors Physical (non-living) factors that shape ecosystems Temperature Precipitation Humidity

What is a biome? Terrestrial community that covers a large area and is characterized by certain soil and climate conditions Particular assemblages of plants and animals.

Biomes Variations in plants and animals help different species survive under different conditions in different biomes. Tolerance - ability to survive and reproduce under conditions that differ from their optimal conditions

The Major Biomes 60°N 30°N 0° Equator 30°S 60°S Temperate grassland Tropical rain forest Temperate grassland This map shows the locations of the world’s major biomes. Other parts of Earth’s surface are classified as mountains or ice caps. Each biome has a characteristic climate and community of organisms. Temperate forest Northwestern coniferous forest Tropical dry forest Desert Temperate woodland and shrubland Boreal forest (Taiga) Tropical savanna Tundra Mountains and ice caps

Biomes Large terrestrial regions characterized by similar climate, soil, plants, and animals Location irrelevant

Biomes Not uniform; consist of a mosaic of patches with different biological communities

Generalized Effects of Elevation and Latitude on Climate and Biomes

Natural Capital: Average Precipitation and Average Temperature as Limiting Factors

Your Turn! Biome Jigsaw Biome Bags

Global Air Circulation, Ocean Currents, and Biomes

Energy Transfer by Convection in the Atmosphere Heat is absorbed and released more slowly by water than by land Moderate weather and climate of nearby lands

Biomes and Climate The climate of a region is an important factor in determining which organisms can survive there. Temperature and precipitation can vary over small distances. Microclimate - the climate in a small area that differs from the climate around it

The Earth’s Surface Features Affect Local Climates Cities Microclimates More haze and smog Higher temperatures Lower wind speeds Causes Bricks, asphalt, and concrete absorb and hold heat Buildings block wind flow

The Earth’s Surface Features Affect Local Climates Mountains Rain shadow effect: moist air blowing inland is forced upward; cools and expands Loses most of its moisture as rain or snow on the windward slope Air dries and warms over leeward side; increases ability to hold moisture and dries ecosystem

Climate Terms Tropical – warm; receives direct or nearly direct sunlight year round Desert - dry Temperate – moderate

Climate Graphs of Three Types of Deserts

Climate Graphs of Tropical, Temperate, and Cold Grasslands

Chaparral Vegetation in Utah, U.S.

Climate Graphs of Tropical, Temperate, and Cold Forests

Stratification of Specialized Plant and Animal Niches in a Tropical Rain Forest

Major Human Impacts on Terrestrial Ecosystems

Tundra

Taiga See Clip

Tropical Rain Forest

Temperate Forest

Temperate Grassland

Desert

Chaparral