Radiation Redux

Previously we discussed how climate sensitivity relates to radiation flux. While I am still looking into Steve F.’s idea examining the radiation/heat balance, I have done some cursory analysis of Roy Spencer’s global CERES and Aqua data of the radiation flux and middle tropospheric temperatures (note that these probably vary, in the short term, about 1.2 times as much as the surface temps, so relating them to radiation will over estimate sensitivity) available here. I have analyzed it in a simplistic manner, not doing smoothing/lead-lag analysis, just simple 31 day slopes, and 365 day averages of those slopes. The average of those averages is 5.28 W m^-2 K^-1 which based on my earlier equations corresponds to an f of -.6 and a climate sensitivity of .75 K for a doubling of CO2. Results like these suggest to me that the satellite flux data strongly support a low climate sensitivity and make higher sensitivities highly implausible. Anyway, here is a plot of the 365 averages of 31 day slopes:

Personally I think there are a lot of reasons why this result may overestimate sensitivity. For one thing, I probably significantly include some bias towards positive feedback by not explicitly accounting for convolution of forcing with feedback. Additionally, if I take into account the amplified variability of tropospheric temperatures compared to the surface, the sensitivity is more like .63 K for a doubling of CO2. This is so strikingly different from the commonly claimed sensitivities that, again, I just can’t see how one can justify them, as they fly in the face of real world measurements.