1. Meteorology and Civilization November 12, 2007

2. Civilization Small groups of people to large urban areas change local meteorology through –Deforestation –Fire –Changes in vegetation cover (CO 2 absorption) –Grazing animals –Mining –Changes in water

3. Civilization Changes in weather and climate are more pronounced on peoples or politics that are in marginal situations –Areas on the fringes of settlement, near uplands, lowlands, polar, or desert limits

4. Civilizations Ancient Egypt after 5000 years before present (ybp) – summer monsoon weakened across tropics Akkadian Empire (Syria) after 4200 ybp – abandoned during period of increased aridity and dust storms Maya (Yucatan) after AD 860 – drought Anasazi (Colorado) AD 1300 - drought

5. El Nino and Civilization Large human populations susceptible to small changes in climate El Nino – small climatic disruption – big killer in areas where population too high Over the past 150 years, its killed 3 times more humans than the Black Death High death rates in animal world because the biosphere has not yet adapted to the phenomenon

6. 1876-78 El Nino

7. El Nino and Civilization Established 5000 years ago –Reconstructed using fish bones Possible causes: –Sea level rise and warming –Land bridge between Americas –Sunspots –Volcanic activity

8. El Nino and Civilization Did El Nino create the Third World? El Nino Drought Belt: China, India, Indonesia, Philippines, Brazil, East and South Africa Ecological Poverty: depletion or loss of entitlement to the natural resource base of traditional agriculture constituted a causal triangle with increased household poverty and state decapitation

9. El Nino and Civilization El Ninos of late 19 th century allowed Europeans to seize land and impoverish populations in the tropics – traditional economy and social structure that created self-sufficiency destroyed

10. 1997-98 El Nino

11. El Nino and Civilization Indonesia 1997-98 Raised air temperatures 1.4°F (equivalent to 100 years of global warming) Droughts brought fires Decades of deforestation had decreased local rainfall, raised temperatures, and exposed flammable peat soils Complete societal breakdown

12. El Nino and Civilization El Nino 1888 produced the Great Ethiopian Famine killing 1/3 of population and 90% of livestock In this region, El Nino produces drought during growing season and monsoons during harvest season 1972-73 El Nino killed 200,000 1982-83 El Nino killed 300,000

13. 1997-98 El Nino in Ethiopia May 1997 warning issued that summer rains would be less Suggestions of planting drought resistance crops and harvesting before unseasonable rains began Chaos averted El Nino and Civilization

14. Civilizations CO 2 began to increase steadily in the atmosphere 8000 years ago through deforestation By 2000 years ago, large tracts of Europe and Asia deforested 1086 England – 85% of arable land was is pasture or crops, 15% forest Methane began increasing 5000 years ago –Rice production, livestock, burning, human waste

15. 2 x CO 2 World

16. In the mid- and high-latitudes, a one- month shift in seasons 2 months more of summer and milder winters In tropics and subtropics, less change in temperature but increasing aridity IPCC mid-range projection means 1000ft increase in sea level this century Acidification of oceans

17. 4 X CO2 World

18. Between 2200 and 2300 No sea ice Trees on Antarctica Elimination of remaining mountain glaciers Elimination of shallow permafrost and tundra Larger magnitude droughts in lower and midlatitudes Feedback mechanisms?

19. Thermohaline Circulation

20. Glacial Expansion