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A record of drought trends under global warming.
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Drought trends
Dr. Peter Carter
Drought trends
USA 2012
Global average temperature increase
All the worlds best food producing regions are in the Northern hemisphere
Any effect on NH food production increases world food prices severely increasing the Global South’s food insecurity.
FIGURE 11 | Mean annual sc-PDSI pm for years (a) 1950–1959, (b) 1975–1984, (c) 2000–2009, (using the 22-model ensemble-mean surface air temperature, precipitation, humidity, net radiation, and wind speed used in the IPCC AR4 from the 20th century
Drought under global warming: a review Aiguo Dai Wiley Jan 2011
Increasing global drought 1950-2009
Palmer Drought Severity Index
PDSI
FIGURE 11 | Mean annual sc-PDSI pm for years (a) 1950–1959, (b) 1975–1984, (c) 2000–2009, (using the 22-model ensemble-mean surface air temperature, precipitation, humidity, net radiation, and wind speed used in the IPCC AR4 from the 20th century
Drought under global warming: a review Aiguo Dai Wiley Jan 2011
Increasing global drought affects most of the worlds best producing regions
Palmer Drought Severity Index
PDSI
FIGURE 11 | Mean annual sc-PDSI pm for years (a) 1950–1959, (b) 1975–1984, (c) 2000–2009, (using the 22-model ensemble-mean surface air temperature, precipitation, humidity, net radiation, and wind speed used in the IPCC AR4 from the 20th century
Drought under global warming: a review Aiguo Dai Wiley Jan 2011
Increasing regional Northern hemisphere drought 1950-2009
Palmer Drought Severity Index
PDSI
http://drought.mssl.ucl.ac.uk/drought.html
Palmer Drought Severity index
Palmer Drought Severity index
Palmer Drought Severity index
12 months UCL algorithm
12 months UCL algorithm
Northern hemisphere
12 months UCL algorithm
12 months UCL algorithm
NASA GISS
NASA GISS
NH SH
Average temp increase
Decadal Northern hemisphere warming trend
Perception of climate change James Hansena,1, Contributed by James Hansen, March 29, 2012
With global warming NH summer heat extremes are increasing.
Rapid loss of Far North and Arctic snow and ice albedo cooling could be expected to increase NH drought. Research indicates the jet stream is being altered with a tendency to prolonging droughts.
Rapid 2012 record loss of Arctic albedo cooling
It is thought that the faster retreat of the spring-summer far North snow cover is a big part of increasing NH drought. Variation from the post-1967 historical norm in June snow cover, June 2012. Dark orange corresponds to between 75 and 100 percent below average. Image: From Rutgers University Climate Lab
Northern Hemisphere
Visible Satellite Monthly Departure (from 1971-2000 mean)
June 2012 record loss of Arctic snow cover albedo cooling
http://bprc.osu.edu/wiki/Greenland_Ice_Albedo_Monitoring
Less albedo reflection cooling
July 2012 record Greenland ice surface loss of albedo cooling Melt water covering the Greenland ice surface lowers albedo
2012 record loss of Arctic sea ice albedo and record loss of Greenland albedo cooling
