1. Anthropocene physical basis of climate spring 2011
Introduction and UNEP reports
Observations
Emissions and other natural forcings
Temperature record, SSTs
Precipitation, Sea level, ENSO, Severe storms
Attribution
Models and predictions
Uncertainties

2. Svante Arrhenius (1859 -1927) Swedish
1884 PhD dissertation electro-chemistry – did not impress advisor, 150 pages, 85 theses.
1896 – Suggested that CO2 could warm the planet, from his work on ice ages. Emission of CO2 may prevent future ice ages.
1903 – Nobel prize in chemistry for work in his dissertation. Most of his these would be unquestioned today

6. Intergovernmental panel on climate change (IPCC) Established by WMO and UNEP and confirmed by UN general assembly December Five reports issued, the latest in 2013
1990 human emissions are increasing atmospheric greenhouse gases, resulting increase 0.3 °C per decade 21st century.
1995 discernible human influence on global climate
2001 surface temperature projected to increase C , and sea level to rise by meters
2007 (Nobel peace prize) Climate warming unequivocal. Most increase in global temperatures since mid-20th century is (>90%) due to increase in anthropogenic greenhouse gas concentrations.
The fifth one is underway. 831 authors selected from 3000 nominations. 3-4 reviewers for each chapter.

7. Human activities have changed the composition of the atmosphere since the pre- industrial era
Watt’s steam engine
Begin industrial period

10. Global mean surface temperatures have increased

16. Precipitation patterns have changed
Annual mean precipitation change: to 2100 Relative to 1990

17. Climate-induced increases in sea level are caused by thermal expansion of the oceans and melting of land ice and ice sheets

18. Sea Levels have risen

19. El Niño years La Niña years
The frequency, persistence and magnitude of El-Nino events have increased in the last 20 years
El Niño years
La Niña years
The El-Nino phenomena leads to floods and droughts throughout the tropics and subtropics

21. Weather-related economic damages have increased

23. Most of the observed warming in the past 50 years is attributable to human activities

24. Humans are perturbing the carbon cycle
Atmosphere
The KP seeks to reduce
total emissions by about 0.2
This is the
“greenhouse” problem
3.3
750
62.3
Estimated Fossil Deposits
6.3
About 16,000
Humans are perturbing the carbon cycle 60
1.6
Plants
Driven by
fossil fuel emissions
500
Soil
92.3 90
2000
…and land clearing
Oceans
39,000
Units Gt C for stores & Gt C y-1 for fluxes
The oceans and land vegetation are currently
taking up 4.6 Gt C per year

25. There are fast and slow processes in the carbon cycle

29. More adverse than beneficial impacts on biological and socioeconomic systems are projected

30. Land areas are projected to warm more than the oceans with the greatest warming at high latitudes
Annual mean temperature change, 2071 to 2100 relative to 1990: Global Average in = 3.1oC

31. Annual mean precipitation change: 2071 to 2100 Relative to 1990
Some areas are projected to become wetter, others drier with an overall increase projected
Annual mean precipitation change: to 2100 Relative to 1990

32. Initially increased agricultural productivity in some mid-latitude regions & reduction in the tropics and sub-tropics even with warming of a few degrees
2020s
2050s
2080s

33. Uncertainties Changes in atmospheric water vapor Changes in cloudiness
Changes in albedo
Aerosol particles
Direct effects
Impact on clouds
Black carbon