Did the Sunspot Cycle Cause the Fall of the Ming Dynasty?

1. Did the Sunspot Cycle Cause the Fall of the Ming Dynasty? Yuk Ling Yung http://www.gps.caltech.edu/faculty/yung CUHK 25 Oct 2004

4. 1644. 3. 29 1944. 3. 29

5. 49 52

11. 68100

14. Surface Top-of-atmosphere Top-of-atmosphere Surface Net Differences Shortwave Kiehl and Trenberth 1997

15. Radiation TOA Quite strong structure due to clouds in ASR and OLR that mostly cancels in the net; some other albedo effects (e.g., Sahara) and land-sea differences, but sun-Earth geometry explains most of pattern. ASR OLR NET Trenberth and Stepaniak, J. Clim. 2003

16. George Hadley (1685-1768), English lawyer and scientist. “I think the cause of the general Trade-winds have not been explained by any of those who have wrote on that subject” (1735) The overturning Hadley cells are the main way the atmosphere transports energy polewards in low latitudes

17. Net Radiation TOA Difference due to ocean transports Total heating Q1-Q2 Trenberth & Stepaniak, 2003

18. Annual mean net surface flux

19. OCEAN-ATMOSPHERE TRANSPORTS Estimate of the partitioning of meridional transports by the atmosphere and ocean. Trenberth and Caron, J. Clim. 2001 At 35° latitude, where the peak polewards transport occurs the atmosphere accounts for 78% (NH) and 92% (SH) of the total. Values estimated from atmospheric analyses agree with direct ocean estimates and those from the best coupled climate models (including CCSM).

20. Departures from annual mean: Equivalent ocean heat content (Ignores annual cycle in ocean heat transports)

21. Changing atmospheric composition: CO2 Mauna Loa, Hawaii Data from Climate Monitoring and Diagnostics Lab., NOAA. Data prior to 1973 from C. Keeling, Scripps Inst. Oceanogr.

22. The enhanced greenhouse effect • CO2 has increased >30% • If CO2 were suddenly doubled then: • atmosphere must warm up to restore balance • via radiation to space • In absence of other changes: warming is 1.2°C • Feedbacks cause complications • Best estimate is warming of 2.5°C • so feedbacks roughly double change • Real world changes complex and • more gradual

23. Annual mean departures from the 1961-90 average for global temperatures, mean 14.0°C, and carbon dioxide concentrations from ice cores and Mauna Loa (1958 on), mean 333.7 ppmv. Karl and Trenberth 2003

24. The Global Mean Radiative Forcing of the Climate System for the Year 2000, Relative to 1750

25. What about changes in the ocean heat content? Changes in Ocean heat content in upper 300 m Changes in Ocean heat content in upper 3000 m Contributes to rise in sea level. Levitus et al. 2000

26. Oceans and Sea Level New global observations by satellite: TOPEX-Poseiden, Jason 1993-2003 Thermal expansion can account for almost all in 1990s, but sea level rise from melting glaciers etc is about 1 mm/yr. Increased use (irrigation) and storage (reservoirs) on land –1 mm/yr. Cazenave and Nerem, 2004 If true: heat going into ocean could be 1.5 W m-2but other estimates are more like 0.95 W m-2 Willis et al. 2004 *0.7 to account for area of ocean.

30. Prince’s Dilemma It happens then as it does to physicians in the treatment of consumption, which in the commencement is easy to cure and difficult to understand; but when it has neither been discovered in due time nor treated upon a proper principle, it becomes easy to understand and difficult to cure. The same happens in state affairs; by foreseeing them at a distance … the evils which might arise from them are soon cured; but when, from want of foresight, they are suffered to increase to such a height that they are perceptible to everyone, there is no longer any remedy. [Machiavelli, The Prince, Chapter 3]

31. The Northern Hemisphere annular mode (NAM) Sea-level pressure regressed on an index of the NAM e.g., Thompson and Wallace 2000

32. The Southern Hemisphere annular mode (SAM) 850-hPa height regressed on an index of the SAM e.g., Kidson, Karoly, Trenberth, etc.

33. Storm activity HIGH LOW HIGH The Northern Hemisphere Annular Mode (NAM) • 30% of winter variance

34. Climate impacts of the NAM Surface temperature regressed on the NAM index Provided courtesy of Todd Mitchell, UW

35. [T] [u] EP Flux 10 30 30 20 Altitude (km) Pressure (hPa) 100 10 300 1000 0 40S 40S 40S EQ EQ EQ 40N 40N 40N 80N 80N 80N Height Field 250 hPa 1000 hPa 50 hPa (c.i. = 3 dam) (c.i. = 1 dam) (c.i. = 0.5 dam) Evolution of Vortex Weakening ONSET

36. [T] [u] EP Flux 10 30 30 20 Altitude (km) Pressure (hPa) 100 10 300 1000 0 40S 40S 40S EQ EQ EQ 40N 40N 40N 80N 80N 80N Height Field 250 hPa 1000 hPa 50 hPa (c.i. = 3 dam) (c.i. = 1 dam) (c.i. = 0.5 dam) Evolution of Vortex Weakening GROWTH

37. [T] [u] EP Flux 10 30 30 20 Altitude (km) Pressure (hPa) 100 10 300 1000 0 40S 40S 40S EQ EQ EQ 40N 40N 40N 80N 80N 80N Height Field 250 hPa 1000 hPa 50 hPa (c.i. = 3 dam) (c.i. = 1 dam) (c.i. = 0.5 dam) Evolution of Vortex Weakening MATURE

38. [T] [u] EP Flux 10 30 30 20 Altitude (km) Pressure (hPa) 100 10 300 1000 0 40S 40S 40S EQ EQ EQ 40N 40N 40N 80N 80N 80N Height Field 250 hPa 1000 hPa 50 hPa (c.i. = 3 dam) (c.i. = 1 dam) (c.i. = 0.5 dam) Evolution of Vortex Weakening DECLINE

39. [T] [u] EP Flux 10 30 30 20 Altitude (km) Pressure (hPa) 100 10 300 1000 0 40S 40S 40S EQ EQ EQ 40N 40N 40N 80N 80N 80N Height Field 250 hPa 1000 hPa 50 hPa (c.i. = 3 dam) (c.i. = 1 dam) (c.i. = 0.5 dam) Evolution of Vortex Weakening DECAY

40. heat flux heat flux VORTEX momentum flux warmer JET JET QBO warmer STRATOSPHERE ALTITUDE (km) TROPOPAUSE TROPOSPHERE ENSO EQUATOR NORTH POLE WINTERTIME EAST More Remarks LOW NAM