Sentences with phrase «about the equilibrium climate»

Yes, the discussion above is about equilibrium climate sensitivity and by picking 2100 (or 2011) we'll be measuring the transient climate sensitivity.

«From the corresponding paper: «our study says nothing about the equilibrium climate sensitivity; it only suggests that the equilibrium greenhouse sensitivity is zero.»

Not exact matches

The Hansen et al study (2004) on target atmospheric CO2 and climate sensitivity is quite clear on this topic: equilibrium responses would double the GCM - based estimates, with very little to be said about transient effects.

We have often made the case here that equilibrium climate sensitivity is most likely to be around 0.75 + / - 0.25 C / (W / m2)(corresponding to about a 3 °C rise for a doubling of CO2).

The real «equilibrium climate sensitivity,» which is the amount of global warming to be expected for a doubling of atmospheric CO2, is likely to be about 1 °C, some three times smaller than most models assumed.

Now, clouds do not make heat exchange imponderable, especially in long term trends of climate analysis, the averages due to what we already know about dynamic equilibrium outcomes and what we observe in the feedbacks going back even greater then 30 years.

While I'm posting (I can see how you guys get into this) I'm also very uncomfortable with your notion of «tacit knowledge:» it certainly seems to be tacit knowledge in the blogosphere that the chances of the climate sensitivity (equilibrium warming on indefinite stabilization at 560ppm CO2, for the non-enthusiasts) being greater than or equal to 6 degrees are too small to be worth worrying about (meaning down at the level of an asteroid strike).

captdallas2 @ 130 — To become more impressed by the estimate of about 3 K for Charney equilibrium climate sensitivity, read papers by Annan & Hargreaves.

In the interview he mentioned the 11 degrees bit and we chatted for a while about how that was a very long term figure (such a climate sensitivity would require a very long time to come into equilibrium) and how we gave no odds at all of that being the case.

Global temperature change is about half that in Antarctica, so this equilibrium global climate sensitivity is 1.5 C (Wm ^ -2) ^ -1, double the fast - feedback (Charney) sensitivity.

Aslo, regarding climate sensitivity a very key thing to remember, especially if sensitivity turns out to be on the high side, is that the «final» equilibrium temperature (Alexi's concerns about there being such a thing aside) calculated from climate sensitivity does not take into account carbon cycle feedbacks OR ice sheet changes.

Question: before talking about simulating climate CHANGE, how long does the climate science community expect it to take before GCM's can reproduce the real world climate PRIOR to human induced CO2 perturbation in terms of: — «equilibrium point», i.e. without artificial flux adjustment to avoid climatic drift, — «natural variability», in terms of, for instance, the Hurst coefficient at different locations on the planet?

Note that «equilibrium» in this thread — up through response 162 — was in terms of climate sensitivity, answering the question about where the «extra heat» comes from.

By focusing soley on the equilibrium climate sensitivity, the authors do miss a lot of features important to people about the overall climate system — for example, what's the equilibrium sensitivity of the carbon cycle to the temperature change brought about by 2X CO2?

Over very long time periods such that the carbon cycle is in equilibrium with the climate, one gets a sensitivity to global temperature of about 20 ppm CO2 / deg C, or 75 ppb CH4 / deg C. On shorter timescales, the sensitivity for CO2 must be less (since there is no time for the deep ocean to come into balance), and variations over the last 1000 years or so (which are less than 10 ppm), indicate that even if Moberg is correct, the maximum sensitivity is around 15 ppm CO2 / deg C. CH4 reacts faster, but even for short term excursions (such as the 8.2 kyr event) has a similar sensitivity.

Scientists often talk about it in terms of the equilibrium climate sensitivity (ECS), which is the long - term temperature increase that we expect from a permanent doubling of atmospheric CO2.

Scientists often talk about it in terms of the equilibrium climate sensitivity (ECS), which is the

In my earlier posting, I tried to make the distinction that global climate change (all that is changing in the climate system) can be separated into: (1) the global warming component that is driven primarily by the increase in greenhouse gases, and (2) the natural (externally unforced) variability of the climate system consisting of temperature fluctuations about an equilibrium reference point, which therefore do not contribute to the long - term trend.

I estimate dT increased from 1980 to 2010 by about 0.4 K. Given equilibrium climate sensitivity of 0.75 K / Wm2, the amount of forcing neutralised by said dT is; 0.4 * 0.75 = 0.3 W / m2.

Equilibrium climate sensitivity greater than about 6 °C — 7 °C is very unlikely.

When I rephrased my question and gave some background to my reason for asking it, you went way outside your area of expertise and turned to stating your opinions (based on you ideological beliefs) about how much your tool says the planet will warm by 2100 (4.4 C you said based on 3.2 C equilibrium climate sensitivity).

Such states may have prevailed in the distant past, but there is nothing about the current Holocene climate to suggest that more than a single equilibrium is within range — we are not close to a new glaciation nor a new «hothouse climate» (although the latter might become possible if continued greenhouse gas emissions were to remain unmitigated for a prolonged interval).

[¶]... Basing our assessment on a combination of several independent lines of evidence, as summarised in Box 10.2 Figures 1 and 2, including observed climate change and the strength of known feedbacks simulated in GCMs, we conclude that the global mean equilibrium warming for doubling CO2, or «equilibrium climate sensitivity», is likely to lie in the range 2 °C to 4.5 °C, with a most likely value of about 3 °C.

And that says nothing about the fact that the Equilibrium Climate Sensitivity is supposed to reflect the rise in temperature following an increase in atmospheric CO2, but what is estimated is the rise in temperature PRECEEDING an increase in atmospheric CO2.

Equilibrium climate sensitivity is likely to be in the range 2 °C to 4.5 °C with a most likely value of about 3 °C, based upon multiple observational and modelling constraints.

Also note that equilibrium climate sensitivity is about half that implied by Earth Systems Sensitivity over the long term [many centuries].

But as yet does not seem interesting enough to make me think differently about the contribution of increased anthropogenic CO2 to the equilibrium climate sensitivity, or even the transient climate sensitivity.

«greenhouse» gases in the atmosphere, since, as anybody but a climate change advocate nut knows, heat rises, most will then waft back harmlessly up into space, as the earth, as all functions seek equilibrium and homeostasis (those scientists believing that is a function of physiology and biology or entropy in a closed rather than open and single ended variant and changing input system don't know what they are talking about) then shifts back into balance, which is really what it is doing all along, since

Say that CO2 doubles by about 2150 — how long before the climate has changed 95 % of the way, at the surface and lower troposphere, from where it is now to its equilibrium?

The 20th and 21st centuries are jointly a transition between equilibrium states, which is what we should be studying if we expect to be able to say anything useful about the likely climate profile of the coming century.

The equilibrium climate sensitivity will be about 50 % greater than this due to the ocean acting as a heat sink, so the ECS will be about 3C, in line with the mean estimate from the models.

Girma, the equilibrium climate sensitivity (estimated at about 3C per CO2 doubling; or about 0.8 C per W / m ^ 2) is not related to the rate of increase, but to how far the increase goes until the Earth is back in energy balance.

Consensus science, despite The Economist misinforming us to the contrary, finds Equilibrium Climate Sensitivity to be about 3 degrees Celsius for each doubling of CO2.

The 95 percent confidence range in this study was between about 1 and 7 °C equilibrium sensitivity, so very low and very high climate sensitivities could not be ruled out, but are relatively unlikely, based on the historical record.

Speculations about the magnitude of the equilibrium climate sensitivity are useless for the purpose of making policy decisions.

The flat prior PDF is an example of a non-informative prior; it is non-informative about the numerical value of the equilibrium climate sensitivity within the range of equilibrium climate sensitivities in which the probability density is constant and not nil.

In summary, GCMs provide another line of evidence that generally supports an equilibrium climate sensitivity between about 2 and 4.5 °C, and the GWPF justification for dismissing these estimates is incorrect.

However, the GWPF report only references the «main results» of Aldrin et al. (2012), whose study actually estimated equilibrium climate sensitivity of about 2.5 or 3.3 °C when accounting for cloud and indirect aerosol effects.

In summary, paleoclimate studies provide one line of evidence that supports an equilibrium climate sensitivity between about 2 and 4.5 °C, and the GWPF justification for dismissing these estimates is weak.

A lower ratio would yield a higher climate sensitivity estimate — for a ratio of 0.6, the range would be 2.2 — 3.8 C. TCR involves an interval of about 70 years, and so it is unlikely that a response to doubled CO2 would exceed 70 percent of the equilibrium value in an interval that short.

Similarly, the climate scenarios were based on 2xCO2 equilibrium GCM projections from three models, where the radiative forcing of climate was interpreted as the combined concentrations of CO2 (555 ppm) and other greenhouse gases (contributing about 15 % of the change in forcing) equivalent to a doubling of CO2, assumed to occur in about 2060.

In view of what Leif Svalgaard says about the smallness of solar variations I'm coming round to the opinion that virtually all climate change that we observe is simply internal variability induced by the oceans and countered in the air all occurring around a relatively stable equilibrium set by sun and oceans.

Or assuming climate models are correct about the delta in forcings, how long can the oceans buffer heat and push out equilibrium?

L&S estimate the equilibrium climate sensitivity to doubled CO2 from their model at «about 1 - 1.5 °C or less».

Also, it is very clear (from the SOD) that there is little dispute about the range of the TCR, but there is still uncertainty about the long tail of the Equilibrium Climate Sensitivity, which (according to the SOD) is still kind of determined by an «expert consensus».

Mark B What, you mean this bit:, we conclude that the global mean equilibrium warming for doubling CO2, or «equilibrium climate sensitivity», is likely to lie in the range 2 °C to 4.5 °C, with a most likely value of about 3 °C.

Alternatively, you can take an estimate of anthropogenic effects (e.g. the calculated change in equilibrium climate mean temp), and from that you can derive a conclusion about the natural variation.

Therein you will find a lot of discussion about discount rates, «leakage», using a U.S. SCC v. a global SCC, average ton of CO2 v. marginal ton, «equilibrium climate sensitivity», and more.

Climate science is tied to the hip of Greenshirt and leftist interests and the best you get from Dr. Curry are vague and false equilibrium about «politics».

Knutti and Hegerl in the November, 2008 Natural Geoscience paper, The equilibrium sensitivity of the Earth's temperature to radiation changes, says various observations favor a climate sensitivity value of about 3 degrees C, with a likely range of about 2 — 4.5 degrees C per the following graphic whereas the current IPCC uncertainty is range is between 1.5 - 4.5 degrees C.