1. Climate Projections Current Weather and News Anthropogenic Projections
IPCC AR4 Carbon Emission Scenarios
Global Temperature Projections
Global Precipitation and Other Projections
For Next Class: Read Ch. 14

4. Projected Emissions to Climate Response

5. Group Discussion
What are some factors affecting future carbon emissions?
What are other anthropogenic activities that should also be accounted for?

6. Factors Affecting Future Carbon Emissions
As long as fossil fuels remain reasonably abundant, future carbon emissions can be approximated by three factors:
Human populations
Change in emissions per person
Changes in efficiency of carbon use
Increase in carbon emissions = increase in population x change in emissions per person x changes in efficiency of carbon use

9. IPCC AR4 Carbon Emission Scenarios
A2 – More Divided World (High Emissions)
A more divided world with independently operating and self-reliant nations, continuously increasing population, regionally oriented economic development, slower and more fragmented technological changes
A1B – More Integrated World (High Emissions)
A more integrated world with rapid economic growth, global population reaching 9 billion in 2050, and convergence of income and way of life, balanced emphasis on all energy sources
B1 – Ecologically Friendly World (Moderate Emissions)
A more integrated world and more ecologically friendly, reductions in materialism and the introduction of clear and resource efficient technologies

10. Projected Emissions to Climate Response
IPCC AR4

11. IPCC AR4

12. IPCC AR4

13. Global Temperature Projections
IPCC AR4

14. Global Temperature Projections
IPCC AR4

15. Global Temperature Projections
Global temperatures are projected to increase by 1.8 to 4.0 °C by 2100
Warming is projected to be most pronounced at higher latitudes of the Northern Hemisphere, especially north of 60 °N
Greatest warming likely to occur over land
Little difference in projected warming among different emission scenarios for the next 25 years

16. Global Precipitation Projections

17. Multi-Model Mean Changes by 2080-2099
IPCC AR4

18. Global Precipitation Projections
Precipitation is projected to increase in the tropics and decrease in the sub-tropics, and increase in the middle latitudes and polar regions.
Precipitation intensity is also projected to increase in most regions of the world.
The number of dry days is projected to increase in much of the tropics, sub-tropics, and middle latitudes.

19. IPCC AR4

20. Multi-Model Mean Sea Ice Projections
IPCC AR4

21. Multi-Model Mean Sea Ice Projections
IPCC AR4

22. IPCC AR4

23. IPCC AR4

24. Summary of Climate Projections
Sea ice, particularly in the arctic during July, August, and September, will continue to decline dramatically.
Warm-phase of ENSO (El Niño) may become more frequent.
Frequency of heat waves is likely to increase.
Length of growing season is likely to increase in mid-latitudes with a corresponding decrease in the number of frost days.
Continued ablation of the Greenland Icecap is likely, with a volume reduction of 20% by 2275 AD.

25. IPCC AR5

26. IPCC AR5

27. IPCC AR5

28. IPCC AR5