Sentences with phrase «feedback equilibrium climate sensitivity»

And it should be possible to measure zero feedback equilibrium climate sensitivity on a small scale if not on a planetary one.

Third, our calculations are for a single fast - feedback equilibrium climate sensitivity, 3 °C for doubled CO2, which we infer from paleoclimate data.

Not exact matches

Then on page 9.5 we read «There is very high confidence that the primary factor contributing to the spread in equilibrium climate sensitivity continues to be the cloud feedback.

Equilibrium sensitivity, including slower surface albedo feedbacks, is 6 °C for doubled CO2 for the range of climate states between glacial conditions and ice - free Antarctica.»

It gets tricky now because the equilibrium climate sensitivity requires a timescale to be defined — barring large hysteresis, it isn't so large going out many millions of years (weathering feedback); there will be a time scale of maximum sensitivity.

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.

One can consider net PR+CR as a response to externally - imposed RF (external forcing) plus feedback «RF», or one can consider PR + CR — feedback «RF» as the response to the externally imposed RF; the later is perhaps more helpful in picturing the time evolution toward equilibrium (and illustrates why the time it takes for an imbalance, equal to: externally imposed RF — climate dependent terms (PR + CR — feedback «RF»), to decay is proportional to both heat capacity and climate sensitivity (defined per unit externally imposed RF).

Depending on meridional heat transport, when freezing temperatures reach deep enough towards low - latitudes, the ice - albedo feedback can become so effective that climate sensitivity becomes infinite and even negative (implying unstable equilibrium for any «ice - line» (latitude marking the edge of ice) between the equator and some other latitude).

The feedback can become zero — or to avoid confusion regarding what is and is not a feedback — the equilibrium climate sensitivity can become infinite (or negative) in some conditions.

part of the utility is that Charney sensitivity, using only relatively rapid feedbacks, describes the climate response to an externally imposed forcing change on a particular timescale related to the heat capacity of the system (if the feedbacks were sufficiniently rapid and the heat capacity independent of time scale (it's not largely because of oceanic circulation), an imbalance would exponentially decay on the time scale of heat capacity * Charney equilibrium climate sensitivity.

But 3,2 °C is the best estimate for equilibrium climate sensitivity (that is when the runs of models consider all the feedbacks).

These additional feedbacks are not still accounted by GCM models, at least those used in IPCC 2007 for equilibrium climate sensitivity.

To translate this into 2xCO2 temperature impact (equilibrium climate sensitivity) means that this would be around 0.6 deg C including all feedbacks, compared to the Myhre et al. estimate before feedbacks of around 1.0 degC and the IPCC mid-range estimate including all feedbacks of 3.2 degC.

It is possible that effective climate sensitivity increases over time (ignoring, as for equilibrium sensitivity, ice sheet and other slow feedbacks), but there is currently no model - independent reason to think that it does so.

[¶]... 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.

One empirical analysis of the type of F+G 06 does not tell that the climate feedback parameter Y is 2.3 ± 1.4 W m ^ -2 K ^ -1 with 95 % certaintyor that the equilibrium climate sensitivity is in the corresponding range 1.0 — 4.1 K. Those limits are obtained only, when the additional assumption of uniform prior in Y is made.

But seriously, I look at your use of terms like «forcing», and «feedback», and «equilibrium climate sensitivity», and «CO2 control knob», and I feel sorta like a modern redox chemist watching a bunch of biologists trying to study the cell by measuring its «phlogiston» characteristics.

The Equilibrium Climate Sensitivity (ECS) The Economist refers to is how much Earth temperatures are expected to rise when one includes fast feedbacks such as atmospheric water vapor increase and the initial greenhouse gas forcing provided by CO2.

I agree that reduction in snow or ice cover resulting from warming constitutes a likely slow positive feedback, but its magnitude may be quite small, at least for the modest changes in surface temperature that can be expected to arise if sensitivity is in fact fairly low, so the Forster / Gregory 06 results may nevertheless be a close approximation to a measurement of equilibrium climate sensitivity.

Imposing a flat prior on an observable property, such as the climate feedback or transient climate response, is equivalent to imposing a highly skewed prior on the equilibrium climate sensitivity, and therefore results in narrower posterior likelihood ranges on the climate sensitivity that exclude very high sensitivities.

Therefore, estimating equilibrium climate sensitivity based on measurements of a climate that's out of equilibrium requires making some significant assumptions, for example that feedbacks will remain constant over time.

- we lack a timescale short enough to consider the forcing as fixed (volcano, CO2 emissions, TSI variations) but long enough to get meaningful climate average (even if such average makes sense, that climate is only weakly chaotic) and certainly too short to reach equilibrium T. Equilibrium climate sensitivity is thus a purely theoretical construct not much more related to reality than the no - feedback senequilibrium T. Equilibrium climate sensitivity is thus a purely theoretical construct not much more related to reality than the no - feedback senEquilibrium climate sensitivity is thus a purely theoretical construct not much more related to reality than the no - feedback sensitivity...

Figure 1: Schematic diagram of the equilibrium fast - feedback climate sensitivity and Earth system sensitivity that includes surface albedo slow feedbacks.

Recently there have been some studies and comments by a few climate scientists that based on the slowed global surface warming over the past decade, estimates of the Earth's overall equilibrium climate sensitivity (the total amount of global surface warming in response to the increased greenhouse effect from a doubling of atmospheric CO2, including amplifying and dampening feedbacks) may be a bit too high.

the «fast» and «slow» feedback climate sensitivity are distinguished by the characteristic timescales of the feedbacks, and not by the time required for the surface temperature to reach a new equilibrium following an imposed forcing.

The diagnosis of global radiative feedbacks allows better understanding of the spread of equilibrium climate sensitivity estimates among current GCMs.

For a slow feedback climate sensitivity of 6 C for doubled CO2, the equilibrium temperature response would be expected to take much longer (at least several millennia), since this response has been shown to be a strong function of climate sensitivity (Hansen et al., 1985).

Webb et al. (2006), investigating a selection of the slab versions of models in Table 8.1, found that differences in feedbacks contribute almost three times more to the range in equilibrium climate sensitivity estimates than differences in the models» radiative forcings (the spread of models» forcing is discussed in Section 10.2).

The Planck response is a negative feedback; including it, the total feedback is -(1 / equilibrium climate sensitivity) and must be negative in order for equilibrium climate sensitivity to be finite.

The IPCC defines climate sensitivity as equilibrium temperature change ΔTλin response to all anthropogenic - era radiativeforcings and consequent «temperature feedbacks» — further changes in TS that occur because TS has already changed in response to a forcing — arising in response to the doubling of pre-industrial CO2 concentration (expected later this century).

We assume that Chylek (2008) is right to find transient and equilibrium climate sensitivity near - identical; that allof the warming from 1980 - 2005 was anthropogenic; that the IPCC's values for forcings and feedbacks are correct; and, in line 2, that McKitrick is right that the insufficiently - corrected heat - island effect of rapid urbanization since 1980 has artificially doubled the true rate of temperature increase in the major global datasets.

Snyder also uses the inferred record of global temperature to estimate equilibrium climate sensitivity including slow feedbacks, sometimes called ESS, suggesting that doubled CO2 (4 W / m2 forcing) would eventually cause global warming of 7 - 13C.