Chapter 7: Climate and Terrestrial Biodiversity

What Factors Influence Climate?

The Earth Has Many Different Climates

• Weather: Local area’s short-term temperature, precipitation, humidity, windspeed cloud cover, and other conditions.
• Climate: Area’s general pattern of the atmosphere over a long period of time.
• Ocean Currents: Prevailing winds and earth rotation.
• Tropical: Equator, intense sunlight
• Polar: Poles, little sunlight
• Temperate: In-between tropical and polar

El Nino- Southern Oscillation

• El Niño-Southern Oscillation: It happens every few years. Prevailing winds in the tropical Pacific Ocean change direction. It affects much of earth’s weather for 1-2 years

Greenhouse Gases Warm the Lower Atmosphere

• Greenhouse gases: H20, CO2, CH4, N2O
• Greenhouse effect: Gases keep the earth warm and habitable
• Moist air rises cool and releases moisture as rain

Earth’s Surface Features Affect Local Climates

• Rain Shadow Effect: Most precipitation falls on the windward side of mountain ranges.

How Does Climate Affect the Nature and Locations of Biomes?

Climate Helps Determine Where Organisms Can Live

• Major biomes: Large land regions with certain types of climate and dominant plant life
• Abiotic factors
    * Latitude
    * Elevation
    * Precipitation
    * Temperature

There Are Three Major Types of Deserts

1. Tropical deserts: Hot and dry most of the year. They have few plants and are often deserts that are seen in movies.
2. Temperate deserts: Temperatures are high in the summer and low in winter and they have more precipitation.
3. Cold deserts: Winters are cold and summers are hot. Precipitation is also low.

• They have fragile ecosystems
    * Slow plant growth
    * Not a lot of species diversity
    * Lack of water

There Are Three Major Types of Grasslands

• Grasslands: This happens in areas that are too moist for deserts and too dry for forests.
• Tropical
    * Savanna: Brazing and browsing animals
• Temperate: Cold winters and hot and dry summers, with tall and short grass prairies
    * Chaparral:
• Artic tundra: Fragile biome with plants close to the ground. They also have short summers and the animals there have thick fur
    * Permafrost: Underground soil that stays frozen
• Alpine Tundra: Above the tree line in the mountains

How Have We Affected the World’s Terrestrial Ecosystem?

Major Human Impacts on Terrestrial Ecosystem

• Deserts
    * Large desert cities
    * Soil destruction by off-road vehicles
    * Soil salinization from irrigation
    * Depletion of groundwater
    * Land disturbance and pollution from mineral extraction
• Grasslands
    * Conversion to cropland
    * Release of CO2 to the atmosphere from burning grassland
    * Overgrazing by livestock
    * Oil production and off-road vehicles in the arctic tundra
• Forest
    * Clearing for agriculture, livestock grazing, timber, and urban development
    * Conversion of diverse forests to tree plantations
    * Damage from off-road vehicles
    * Pollution of forest streams
• Mountains
    * Agriculture
    * Timber extraction
    * Mineral extraction
    * Hydroelectric dams and reservoirs
    * Increasing tourism
    * Urban air pollution
    * Increased ultraviolet radiation from ozone depletion
    * Soil damage from off-road vehicles