måndag 30 september 2013
Thomas Stocker's Defense of IPCC Climate Models at Variance with Observations
Global temperature increased according to observations in the periods 1920 - 40 and 1978 - 1996 with about 0.35 C, while the temperature was slightly decreasing in the periods 1880 - 1920, 1940 - 1978, 1997 - 2013.
The main argument used by IPCC co-chairman Thomas Stocker when defending the climate models of IPCC AR5 predicting steady warming, was that the 17 year period 1997 - 2013 with no warming was too short to allow any conclusion that CO2 forcing was too small to be observed, while the 18 year period 1978 - 1996 with warming was long enough be able to attribute with 95% likelihood the warming to CO2 forcing. Stocker clarified the argument by adding that a period of 30 years would be required to be able to detect a trend in global cooling.
PS1 The temperature curves for the periods 1920 - 1950 and 1973 - 2013 are very similar with first warming and then slight cooling, only shifted with a steady rise of about 0.5 C/century after the Little Ice Age. The rise 1920 - 1940 is not attributed to CO2 by IPCC while the rise 1976 - 1996 is. The logic is missing.
PS2 The above graph produced by IPCC appears to present lower than actual temperatures before 1960 thus enhancing the warming thereafter.
Aviation fuel usage is interesting compared with temperature anomalies.
SvaraRaderahttp://i629.photobucket.com/albums/uu20/blouis79/globaltemp_aviationfuel.png