tag:blogger.com,1999:blog-8205333.post1164858028902103650..comments2023-10-16T11:28:03.544+00:00Comments on Anomaly UK: Basic climate questionAnomaly UKhttp://www.blogger.com/profile/04780148789321563441noreply@blogger.comBlogger1125tag:blogger.com,1999:blog-8205333.post-36640974297549733822012-02-23T16:25:28.890+00:002012-02-23T16:25:28.890+00:00there would have to be net negative feedback
As fo...<i>there would have to be net negative feedback</i><br />As for 'negative feedbacks' that keep the climate within certain bounds, these are principally not what you would call 'feedbacks' but the various physical constraints and limits. To list a few, the amount of incident solar radiation does not change very much and does not depend on what the climate does. The amount of infrared radiation the Earth emits is subject to radiation laws: the hotter the body, the more it radiates. A black body twice as hot radiates 16 times as much energy; that's a strong negative feedback for you. The Earth's albedo cannot change very much either, and some changes to it (e.g. volcanic ash) quickly disappear. The distribution of land masses that affects albedo, ocean currents, winds etc. is one more climate-independent constraint. <br /><br /><i>That just doesn't seem remotely plausible to me.</i><br />However that is just the way it is. Climate is a stochastic dynamical system with multiple equilibria, and potentially any perturbation can affect transitions between the equilibria. The flip side of this coin is the impossibility of knowing exactly what perturbation has caused or will cause the system to transition from one state to another, to pinpoint <i>the</i> straw that breaks the camel's back, so to speak. And a third side is that after a time the 'memory' of the perturbation dissipates, and it becomes impossible to say (looking just at the climate) that there has been a perturbation at all. The climate resembles one of those funny pendulums with magnets: it bobbles randomly within the bounds set by the power being imparted by the magnets' kicks (incident solar radiation) and trickling out through friction (thermal radiation). Nudge it and its motion will visibly change, but as it bobbles on it will soon become impossible to tell that you've ever nudged it. If your nudge has added energy it will be lost through friction, if it has removed energy it will be replenished by the magnets.<br />I am probably not explaining this very well. Please don't hesitate to ask questions!Anonymousnoreply@blogger.com