Climate and Terrestrial Biodiversity Chapter 7 - Miller

What is Climate? Definition: A region’s long-term atmospheric conditions – tens to thousands of years. Determined by: 1) Average Temperature 2) Average Precipitation

What influences Climate? Four Factors: 1) Latitude 2) Altitude 3) Bodies of Water 4) Planetary Winds/Ocean Currents

Factors that Affect Climate Latitude: Temperatures vary with latitude due to varying angle, intensity, and duration of insolation. Moisture varies with latitude. At the equator warm rising air cools and creates clouds, precipitation and humid climates * This factor is enhanced by seasonal variations

Reasons for the Seasons 1) Tilt of Earth’s Axis 2) Revolution 3) Parallelism

Seasonal Effect

Variations in Insolation Intensity greatest at: Equator – Equinoxes T.O. Cancer – Summer Solstice T.O. Capricorn – Winter

Variations In Insolation Duration of Insolation: Varies with latitude and the seasons

Elevation Temperature: Higher altitudes have a cooler climate As air rises, it expands and cools Less greenhouse gasses to absorb long wave radiation

Elevation Moisture: Higher altitudes have more precipitation Air temperatures are low and water vapor capacity decreases Air reaches dew point Condensation forms clouds and it rains/snows

Latitude and Vertical Zonation Hiking up a mountain is similar to traveling toward the poles

Mountain Barriers Windward side: Air rises Expands Cools Climate is cool and moist

Mountain Barriers Leeward side: Air sinks Compresses warms Climate is warm and dry

Mountain Barriers Elevation:

Factors that Affect Climate Marine Climate: Close proximity to water Cooler summers Warmer winters Small temperature range Temperature moderated by water’s high specific heat

Factors that Affect Climate Continental Climate: Inland Warmer summers Cooler winters Large temperature range Temperatures are moderated by dry air’s low specific heat

Factors that Affect Climate Planetary Winds: Caused by the air pressure differences on Earth and the effects of Earth’s rotation

Transfer of Energy Uneven Heating Causes: High Pressure Low Pressure Cool/Dry Dense Descending Air Low Pressure Warm/Moist Low Density Rising Air

Planetary Winds

Global Air Circulation Hadley Cells – Vertical currents that distribute heat and moisture over Earth’s Surface Result: Climatic Zones Descending Air –Cool, dry Ascending Air – Warm, moist

Global Ocean Currents Caused By:

Biomes Definition: Large, relatively distinct terrestrial region characterized by similar: Climate Soil Plants Animals

Climatograms