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.

Advertisements

3 Responses to “Radiation Redux”

  1. Climate as A Differential Equations Problem « Hypothesis Testing Says:

    […] used to estimate lambda from considering changes in the radiation flux with temperature (and also estimated the relationship between changes in flux and temperature). Let’s consider those equations for a moment: Equation […]

  2. Climate as A Differential Equations Problem « the Air Vent Says:

    […] used to estimate lambda from considering changes in the radiation flux with temperature (and also estimated the relationship between changes in flux and temperature). Let’s consider those equations for a […]

  3. Can you isolate a volcanic temperature signal in the temperature data? | Hypothesis Testing Says:

    […] provides evidence that the sensitivity is pretty small, and is in the range of my estimates from feedback fluxes, and the Faint Young […]

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s


%d bloggers like this: