1. © 2007, John Wiley and Sons, Inc. Physical Geography by Alan Arbogast Chapter 9 Global Climates Lawrence McGlinn Department of Geography State University of New York - New Paltz

2. © 2007, John Wiley and Sons, Inc. Global Climates Climate & Factors Affecting It Köppen Climate Classification Geography of Köppen Climates Global Climate Change

3. © 2007, John Wiley and Sons, Inc. Weather vs. Climate Weather – state of the atmosphere at a specific place and time on Earth’s surface. Climate – average values of weather elements, such as temp and precipitation, over an extended period of time

4. © 2007, John Wiley and Sons, Inc. Variables that Influence Climate Latitude – intensity of radiation, length of day Seasonality – annual variation of sun angle Air Circulation – predictable – weather systems Maritime/Continental – proximity to water can increase precip. and reduce temp range Topography – local topography can impact climate, e.g. windward vs. leeward side of mts.

5. © 2007, John Wiley and Sons, Inc. Variables that Influence Climate

6. © 2007, John Wiley and Sons, Inc. Köppen Climate Classification System Describes world climates based on: Avg monthly temp Avg monthly precip Total annual precip 6 major climate groups based on latitude: A-E & H Further subdivided by temp and precip.

7. © 2007, John Wiley and Sons, Inc. Major Climate Groups

8. © 2007, John Wiley and Sons, Inc. Climate Specifics

9. © 2007, John Wiley and Sons, Inc. Global Distribution of Climates

10. © 2007, John Wiley and Sons, Inc. Tropical Climates (A) Straddle Equator from 25º N to 25º S Avg. Monthly temp. exceeds 18ºC (64ºF) Subdivided by precipitation: Af – tropical rainforest – wettest Am – tropical monsoon Aw – tropical savanna - drier

11. © 2007, John Wiley and Sons, Inc. AfAf AmAm AwAw Tropical Climates (A) Tropical Savanna Climate

12. © 2007, John Wiley and Sons, Inc. Ecuador Tropical Rainforest - Af Northern Australia Tropical Savanna - Aw

13. © 2007, John Wiley and Sons, Inc. Arid/Semi-Arid Climates (B) Poleward of A climates on all continents Subsiding air from STHs - Moister on fringes Subdivided by temp & moisture: BWh – 15-30º N & S – hot - little precip BWk - <15 cm precip/yr – high temp range BSh – more temp range & precip than BWh BSk – rainshadow – convectional precip – high temp range

14. © 2007, John Wiley and Sons, Inc. Arid/Semi-Arid Climates (B) BWh BSh BWkBSk

15. © 2007, John Wiley and Sons, Inc. Jordan – Hot, Low-latitude Desert - BWh Northcentral China – Cold, mid latitude Desert - BWk Eastern Colorado, USA Cold, mid latitude Steppe - BSk California, USA - Hot, low latitude Steppe - BSh

16. © 2007, John Wiley and Sons, Inc. Mesothermal Climates (C) 20º- 60º N & S – where most people live A warm and a cool season Cfa, Cwa – hot, humid summer – east side of continents – 20-35º N & S Csa, Csb – west coast of continents – near 35º N & S – winter wet season, dry summer Cfb, Cfc – west coast of continents – 35-60º N & S – mP air & orographic processes

17. © 2007, John Wiley and Sons, Inc. Mesothermal Climates (C) CfaCfb Csa Moist Subtropical Climate

18. © 2007, John Wiley and Sons, Inc. Southern California – Mediterranean Dry-Summer Climate - Csa Western Washington – Marine West-Coast Climate - Cfc Marine West Coast Climates

19. © 2007, John Wiley and Sons, Inc. Microthermal Climates (D) Poleward of C climates, 35º- 60º N & S Long winters, limited summer warmth Dfa, Dwa – large annual temp range – jet stream & cyclonic precip, most in summer Dfb, Dwb – very large annual temp range – mild summer, harsh, dry winter Dfc, Dwc, Dwd – long, bitter winters - short, cool summers – little precip – highest annual temp range on Earth

20. © 2007, John Wiley and Sons, Inc. DfaDwaDfbDwbDfc Microthermal Climates (D)

21. © 2007, John Wiley and Sons, Inc. Eastern US – Humid Continental Hot-Summer Climate - Dfa Northern Michigan – Humid Continental Mild-Summer Climate - Dfb Central Canada - Subarctic Climate – Dfc

22. © 2007, John Wiley and Sons, Inc. Polar Climates (E) Latitudes >70º N & S Long, cold winters w/little precip. 2 Subcategories: ET – temp moderated by ocean – precip mostly June-Oct.- polar high dominates EF – interior Greenland and Antarctica – always brutally cold – polar desert

23. © 2007, John Wiley and Sons, Inc. Polar Climates (E) ETEF Near Nome, AK – Tundra Climate - ET

24. © 2007, John Wiley and Sons, Inc. Highland Climates (H) Associated with large mtn ranges, e.g. Andes, Rockies, Alps, etc. Cooler/colder than surrounding lowlands, even in tropical or equatorial regions Often wetter than surroundings due to orographic precip. Remote Sensing and Climate

25. © 2007, John Wiley and Sons, Inc. Global Climate Change Major environmental issue of next century Highly politicized Vast majority of climate scientists agree global change is occurring Vast majority also agree it is due to anthropogenic influences

26. © 2007, John Wiley and Sons, Inc. Carbon Cycle Carbon dioxide (CO 2 ) traps longwave radiation Carbon in all living things It moves among reservoirs – only 1% actively in cycle at any one time Reservoirs include: atmosphere, marine sediments, plants, animals, coal deposits, etc. Humans have accelerated transfer from deposits to atmosphere

27. © 2007, John Wiley and Sons, Inc. Carbon Cycle (Billions of Metric Tons)

28. © 2007, John Wiley and Sons, Inc. Fossil Fuel Petroelum, Coal, Natural Gas Dominant energy source for world 98 tons of prehistoric plant matter for each gallon of gasoline US : 5% of world pop consumes 25% of energy 1950 – 1.6 B met tons carbon released 1997 – 6.3 B met tons carbon released 1850 – CO 2 concentration 288 ppm 2001 - CO 2 concentration 370 ppm

29. © 2007, John Wiley and Sons, Inc. Changes in Atmospheric CO 2 since 1850

30. © 2007, John Wiley and Sons, Inc. Past Climate Change Records show 1ºC rise since 1880 Prior to recorded data, use Proxy Data: Palynology - pollen in lake sediments shows veg type - > 15,000 year record Dendrochronology - tree rings show growth patterns – 9000-yr record Ice Cores – air trapped over 650K yrs shows past CO 2 concentrations

31. © 2007, John Wiley and Sons, Inc. Global Temp Change since 1880

32. © 2007, John Wiley and Sons, Inc. Greenhouse Gas-Temp Correlation from Ice Cores

33. © 2007, John Wiley and Sons, Inc. Future Scenarios IPCC predicts accelerated warming through 2100 Greater warming at higher latitudes Positive climate feedback: In warmer Arctic ice melts→less reflection→ greater warming Warmer Earth → more evaporation → more vapor to trap heat, but also more clouds ??? Rising sea levels, shifting agricultural zones, spread of insect-borne disease, more extreme events such as hurricanes and snowstorms, uneven regional effects