This will confuse you even more. λ is often defined positive as in
dF = λ dT
Positive forcing leads to positive warming. The more general situation is when there is an imbalance you get (H is the heat content)
dF = dH/dt + λ dT
In a steady state, the forcing change is balanced by a warming. λ depends on feedbacks and gets smaller for positive feedbacks.
Comment on Week in review – science edition by Jim D
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Comment on Week in review – science edition by Robert I. Ellison
“This is called the Planck feedback because it is fundamentally due to the Planck blackbody radiation law (warmer temperatures = higher emission).”
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Comment on Week in review – science edition by Jim D
Known more precisely as the Planck Response to avoid confusion with actual feedbacks that act in proportion to it, and are quite different things. A feedback can’t exist without a response, but a response can exist without a feedback.
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Comment on Week in review – science edition by Robert I. Ellison
“Given sufficient time, the system will reach its new equilibrium temperature, at which point
dΔTs/dt=0
And the perturbation budget is thus
0=R+λΔTs
or
ΔTs=−R/ λ
where R is the forcing in W m^−2 and λ is the feedback in W m^−2 K^−1 .”
λ is always negative – ΔTs approaches infinity as λ approaches zero. Net positive feedbacks (to TOA radiant energy) would lead to instability.
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Comment on Week in review – science edition by Robert I. Ellison
A warming from forcing can’t exist without feeding back into energy dynamics at toa – known as the Planck feedback. It is distinguished from the Planck response – which is a temperature response considering only the temperature (Planck) feedback. The Planck response lacks any physical meaning – the Planck feedback is the fundamental energy dynamic driving the planet to a transient TOA energy equilibrium at maximum entropy. Not understanding this is to not understand Earth geophysics at all.
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Comment on Week in review – science edition by Jim D
Having a negatively defined λ is the other odd thing about those equations. More often you will see that a positive forcing is proportional to a positive dT with a positive λ.
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Comment on Week in review – science edition by Robert I. Ellison
The form of the equation emerges from the derivation as shown – the sign of the net feedbacks emerges from summing the individual components. If λ were net positive – we wouldn’t be arguing about it.
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Comment on Week in review – science edition by Robert I. Ellison
Was anyone planning on telling him that the link gives a 404 error? Or didn’t anyone try it.
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Comment on Week in review – science edition by Jim D
The Planck Response is the default response of a passive body to forcing, about 1 K for each 3.3 W/m2 added forcing. Note this is positive because you get warming for a positive forcing. The Earth doesn’t have the Planck Response because it also has feedbacks, so it ends up being about 1 K for only 1.5 W/m2, a positive feedback because it warms more than a Planck body for a given forcing which is only possible because of a feedback loop that modifies the original response.
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Comment on Week in review – science edition by Jim D
Everyone else uses a positive λ. Just saying. It makes more sense because positive forcing leads to warming and it is closely related to the climate sensitivity that is also positive.
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Comment on Week in review – science edition by Robert I. Ellison
words words words…
The Planck response is this unphysical notion of warming from forcing that negates the forcing with the temperature feedback alone. When you actually sum the listed feedbacks – some of which are positive – there is a more realistic warming estimate – depending of course on how realistic the forcing and feedback estimates are.
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Comment on Week in review – science edition by Robert I. Ellison
ECS = -R/ λ = -3.7/-1.5 = 2.5 K – with a large uncertainty – perfect mathematical logic. But you can do what you like with the signs as long as it makes physical sense.
-1.5 W m^-2 K&-1 being about the sum of IPCC feedbacks.
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Comment on Week in review – science edition by Robert I. Ellison
Forcing creates warming which creates positive and negative feedbacks – with the negative temperature feedback dominating and driving the planet to energy equilibrium at TOA. These are simple physical realities.
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Comment on Week in review – science edition by rovingbroker
Another morning when the “Recent Comments” section lists only two commenters: Jim D and Robert I. Ellison.
Why don’t you two exchange e-mail addresses and leave the rest of us alone?
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Comment on Week in review – science edition by Scott Koontz
10 year cherry picks are not interesting at all. Still warming, still primarily CO2, and not the sun.
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Comment on Week in review – science edition by Rob Starkey
The rate of warming is what is not alarming.
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Comment on Week in review – science edition by Scott Koontz
To the people who study this, the rate of warming is what is most alarming. To the people who finally and grudgingly admitted that the earth is warming, they now pretend the rate is not alarming at all.
Who you going to believe? I choose to listen to the scientists who study climate.
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Comment on Week in review – science edition by frankclimate
Sheldon, I also read both papers (Lewa, Mann) and I was not amused. They criticise about 200 papers ( also some kind of consensus about the “pause”), most of them were written with the knowledge of the data up to 2014. When one looks with the eyes of the bullied scientists at this time it gives this:
IMO there was every reason to make thoughts about the source(s) of this behaviour. This is how science works.
To write something about statistics with the knowledge of 2018 and making such strong statements about the impact of the “pause research” on policy ( “it took the momentum…”) is far from science IMO.
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Comment on Week in review – science edition by jim2
Yep, it’s always the future that’s bleak. NOW we have to wait 10 more years. And 10 years from now, we’ll have to wait another 50. Give it up already.
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Comment on Week in review – science edition by Jim D
Clearly you have not understood that I am agreeing warming causes more emission.
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