1. Climate & Terrestrial Biodiversity
Ch. 7

2. Climate is what we expect;
What is Climate?
Weather - short term; today
Climate - general atmospheric or weather conditions over time
Climate is what we expect;
weather is what we get.

3. Climate varies over the surface of the earth
2 main factors:
Wind - air circulation
Ocean currents
Move warm & cold moisture from one place to another, but unevenly

4. Focus on AIR
Air circulates warmth & moisture from the tropics to other places

5. Focus on AIR 3 forces responsible:
Tilt of the earth - Earth is heated unevenly

6. Focus on AIR 3 forces responsible
2. Rotation of the Earth on its axis
equator spins faster than poles
Warm air rising over equator goes N or S then deflected E or W
creates “prevailing winds” - major surface winds that blow almost continuously

11. Focus on AIR 3 forces responsible
3. The water cycle
heat from the sun evaporates ocean water and transfers it to air
this creates convection cells that circulate heat, air, and moisture

12. Focus on OCEAN CURRENTS
Prevailing winds blow over ocean & move surface water --> currents

13. Focus on OCEAN CURRENTS
Currents move warm water to other places
Changes vegetation & climate of the area, especially near the coastline

14. Focus on OCEAN CURRENTS
Continents and wind currents shape path of ocean currents

15. Focus on OCEAN CURRENTS
Currents go clockwise in Northern Hemisphere
Currents go counterclockwise in Southern Hemisphere

16. Focus on OCEAN CURRENTS
Also vertical mixing of water
Cold water sinks - more dense, saltier
Warm water rises - less dense, less salty

17. OCEAN CURRENTS + AIR CURRENTS 4EVER
Ocean currents affected by wind
Heat from ocean affects air circulation patterns

18. For Example El Niño Southern Oscillation (ENSO)
Changes global weather over 2/3 of the planet due to a relatively small change in wind speed

19. So…
Air circulation + winds + ocean currents + continents in the way = 6 giant convection cells that shape climate
(3 in north, 3 in south)
Warm wet air rises
Cool dry air sinks

20. The Atmosphere
Greenhouse gases warm the Earth
H2O, CO2, CH4, N2O

21. How they work Light from sun passes through atmosphere
Surface absorbs heat
Heat radiates back up
Some escapes to space
Some absorbed by greenhouse gases - its good! :)

22. Climate Change (global warming)
LOTS and LOTS of evidence supports the hypothesis that humans are contributing excess greenhouse gases to the atmosphere - altering earth’s climate
90-99% sure of this
Why not 100%
Precautionary Principle

23. Earth’s Surface Features also affect climate
Rain shadow effect
Windward side wet
Leeward side dry

25. All of this creates BIOMES
High Mountains
Polar Ice
Arctic Tundra
Temperate Grassland
Tropical grassland (savanna)
Chaparral
Temperate Coniferous forest
Temperate deciduous forest
Tropical rainforest
Tropical dry forest
Tropical Desert
Temperate rain forest
Temperate desert
Cold desert
Taiga
Tropical and subtropical coniferous forest
Pond
Inland wetlands (swamps, marshes, prarie potholes)
Mangrove forest
Riparian (rivers and surrounding area)

26. All of this creates BIOMES
High Mountains
Polar Ice
Arctic Tundra
Temperate Grassland
Tropical grassland (savanna)
Chaparral
Temperate Coniferous forest
Temperate deciduous forest
Tropical rainforest
Tropical dry forest
Tropical Desert
Temperate rain forest
Temperate desert
Cold desert
Taiga
Tropical and subtropical coniferous forest
Pond
Littoral, intertidal zone
Mangrove forest
Kelp forest
Coral reef
Neritic zone (coastal waters)
Continental shelf
Pelagic zone (open sea)
Benthic zone (bottom of lakes and oceans)
Hydrothermal vents
Cold seeps
Estuaries
Riparian (rivers and surrounding area)
Inland wetlands (swamps, marshes, prarie potholes)

27. Climate Helps Determine Where Organisms Can Live
Major biomes
Large land regions with certain types of climate and dominant plant life
Not uniform
Mosaic of patches
Change with latitude and elevation

28. Climate Helps Determine Where Organisms Can Live (cont’d.)
Hot
Wet
Dry

30. 3 types of Desert, Grasslands & Forests …know these!
Tropical
Temperate
Cold
Desert – annual precipitation low and often scattered through the year
Grasslands occur in:
Interior continents too moist for deserts and too dry for forests
Forests – lands dominated by trees

31. Humans Have Disturbed Much of the Earth’s Land
About 60% of the world’s major terrestrial ecosystems are being degraded
The human ecological footprint is spreading across the globe

33. Size and Locations of Biomes Can Change
Biomes are not fixed
They change as the climate changes
Human activities are likely to affect biome placement in the future

34. Three Big Ideas Differences in climate:
Based on long-term differences in average temperature and precipitation
Largely determine the types and locations of the earth’s deserts, grasslands, and forests
The earth’s terrestrial systems provide important ecological and economic services
Human activities are degrading and disrupting many of the ecological and economic services provided by the earth’s terrestrial ecosystems

35. Tying It All Together: A Temperate Deciduous Forest and Sustainability
Climate plays a key role in determining the nature of terrestrial ecosystems
The earth’s dynamic climate system helps distribute heat from solar energy and recycle the earth’s nutrients
In nature, everything is connected