1. Climate and Terrestrial Biodiversity
Chapter 7

2. 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.

3. 7-1 What Factors Influence Climate?
Weather is a local area’s short-term physical conditions such as temperature and precipitation.
Climate is a region’s average weather conditions over a long period of time.
“Climate is what we expect, weather is what we get.”
-- Mark Twain

4. 7-1 What Factors Influence Climate?
Climate varies from place to place because the air circulation in the 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

5. 7-1 What Factors Influence Climate?
Uneven heating of Earth’s surface by the sun:
Equator vs. poles – round planet
Earth’s tilt – 23.5º
Albedo – how strongly it reflects light
Insolation – solar radiation received by a given area in a given time (kWh/m2/day)

6. 7-1 What Factors Influence Climate?

7. 7-1 What Factors Influence Climate?
Rotation of Earth on its axis
Rotation is FASTER at equator than poles…causes the Coriolis Effect – the deflecting of air masses by the rotation of the Earth
Also causes complex global air circulation
Wind belts produce ocean surface currents

8. 7-1 What Factors Influence Climate?
If the Earth didn’t rotate, we could expect wind to flow in the following manner…

9. 7-1 What Factors Influence Climate?
Instead it looks like this…

10. 7-1 What Factors Influence Climate?
Properties of air, water, and land
Convection cells form due to interaction between air/water/land

11. 7-1 What Factors Influence Climate?

12. 7-1 What Factors Influence Climate?
Heat and moisture are distributed over the earth’s surface by vertical air currents, which form six giant convection cells at different latitudes.

13. 7-1 What Factors Influence Climate?
Ocean Currents are caused by:
Prevailing wind belts
Earth’s rotation
Ocean currents influence climate by distributing heat from place to place.
The temp. of the water affects the temp. of the air

14. Generalized Map of the Earth’s Current Climate Zones
7-1 What Factors Influence Climate?
Generalized Map of the Earth’s Current Climate Zones

15. 7-1 What Factors Influence Climate?
The Greenhouse effect keeps the entire planet warmer than it would be without it
Greenhouse gases:
Water vapor – H2O
Carbon Dioxide – CO2
Methane – CH4
Nitrous Oxide – N2O

16. 7-1 What Factors Influence Climate?
The Rain Shadow Effect
Interactions between land and oceans and disruptions of airflows by mountains and cities affect local climates.
Microclimate – local and regional climates different than the larger regional climate

17. 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.

18. 7-2 How Does Climate Affect the Nature and Locations of Biomes?
Climate Affects Where Organisms Can Live
Biomes – large terrestrial regions characterized by similar climate, soil, plants, and animals
Biomes vary by, and are determined by:
Latitude and elevation
Annual precipitation
Temperature

19. 7-2 How Does Climate Affect the Nature and Locations of Biomes?

20. Generalized Effects of Elevation and Latitude on Climate and Biomes
7-2 How Does Climate Affect the Nature and Locations of Biomes?
Generalized Effects of Elevation and Latitude on Climate and Biomes

21. Average Precipitation and Average Temperature as Limiting Factors
7-2 How Does Climate Affect the Nature and Locations of Biomes?
Average Precipitation and Average Temperature as Limiting Factors