
But those changes are the result of increased rising air over the warm pool, and that extra rising air must - through mass continuity - be exactly matched by increased sinking air away from the warm pool…possibly thousands of miles away.

So, why can’t feedbacks be evaluated regionally? Because a change in one region will, in general, affect other regions, through changes in atmospheric vertical circulation systems.įor example, if the Pacific warm pool was to warm, we might expect increases in clouds and precipitation there.

Until a better term comes along which better reflects the recursive nature of the forcing-response process, we are stuck with it.) (And for those who object to the use of “feedback” in a climate context, sorry.
#SHILLELAGH VAPOR FREE#
The contribution to water vapor feedback by the atmospheric boundary layer is almost certainly positive, but the free-tropospheric contribution to water vapor feedback is much more uncertain, since it depends upon microphysical processes within precipitation systems which are the source of free tropospheric air. This so-called “Planck effect” is what stabilizes the climate system against runaway change.Ĭloud feedbacks are generally considered to be the most uncertain, and could be positive or negative (I believe they are negative). The single largest feedback is negative: the increase in infrared energy lost to space as temperature increases. Feedbacks only make sense in the global average.įirst, a summary of what climate feedbacks are, by definition: In response to a surface temperature change, other changes in the climate system (clouds, etc.) can either magnify (positive feedback) or reduce (negative feedback) the original temperature change. I will admit that what happens on a regional basis determines net global climate feedbacks, but feedbacks cannot be evaluated regionally.

Whenever I see reference to the regional nature of climate feedbacks, I cringe.
