Sentences with phrase «higher climate sensitivity estimates»

However, the report is biased towards Lewis» preferred approach, finding poor excuses to reject the many other methods that arrive at higher climate sensitivity estimates.

In the report, they find reasons to dismiss the many studies and varying approaches that arrive at higher climate sensitivity estimates, and fail to discuss the shortcomings of the lower sensitivity studies that they prefer.

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.

Some reports have stated if we have 15 years of no warming despite continued increase of CO2 to record levels, this will constitute a direct falsification of the model - based high climate sensitivity estimates.

Not exact matches

Note that the old GISS model had a climate sensitivity that was a little higher (4.2 ºC for a doubling of CO2) than the best estimate (~ 3ºC) and as stated in previous years, the actual forcings that occurred are not the same as those used in the different scenarios.

Whether the observed solar cycle in surface temperature is as large as.17 K (as in Camp and Tung) or more like.1 K (many previous estimates) is somewhat more in doubt, as is their interpretation in terms of low thermal inertia and high climate sensitivity in energy balance models.

Using Mg / Ca paleothermometry from the planktonic foraminifera Globigerinoides ruber from the past 500 k.y. at Ocean Drilling Program (ODP) Site 871 in the western Pacific warm pool, we estimate the tropical Pacific climate sensitivity parameter (λ) to be 0.94 — 1.06 °C (W m − 2) − 1, higher than that predicted by model simulations of the Last Glacial Maximum or by models of doubled greenhouse gas concentration forcing.

Forest et al. (2006) demonstrate that the inclusion of natural forcing affects the estimated PDF of climate sensitivity since net negative natural forcing in the second half of the 20th century favours higher sensitivities than earlier results that disregarded natural forcing (Forest et al., 2002; see Figure 9.20), particularly if the same ocean warming estimates were used.

I would also bet that Hansen's estimate of climate sensitivity at 3 degrees Centigrade is too high.

(in general, whether for future projections or historical reconstructions or estimates of climate sensitivity, I tend to be sympathetic to arguments of more rather than less uncertainty because I feel like in general, models and statistical approaches are not exhaustive and it is «plausible» that additional factors could lead to either higher or lower estimates than seen with a single approach.

But I understand sea level rise right now is actually towards the upper end of estimates so this suggests either climate sensitivity is towards the high end, or ice sheets are very sensitive to low or medium climate sensitivity.

Using Mg / Ca paleothermometry from the planktonic foraminifera Globigerinoides ruber from the past 500 k.y. at Ocean Drilling Program (ODP) Site 871 in the western Pacific warm pool, we estimate the tropical Pacific climate sensitivity parameter (λ) to be 0.94 — 1.06 °C (W m − 2) − 1, higher than that predicted by model simulations of the Last Glacial Maximum or by models of doubled greenhouse gas concentration forcing.

As stated last year, the Scenario B in that paper is running a little high compared with the actual forcings growth (by about 10 %)(and high compared to A1B), and the old GISS model had a climate sensitivity that was a little higher (4.2 ºC for a doubling of CO2) than the best estimate (~ 3ºC).

This is enough to matter, but it's no more scary than the uncertainty in cloud feedbacks for example, and whether they could put us on the high end of typical climate sensitivity estimates.

The high end of current estimates for climate sensitivity are already in very negative and serious terratory.

The IPCC range, on the other hand, encompasses the overall uncertainty across a very large number of studies, using different methods all with their own potential biases and problems (e.g., resulting from biases in proxy data used as constraints on past temperature changes, etc.) There is a number of single studies on climate sensitivity that have statistical uncertainties as small as Cox et al., yet different best estimates — some higher than the classic 3 °C, some lower.

[T] here have now been several recent papers showing much the same — numerous factors including: the increase in positive forcing (CO2 and the recent work on black carbon), decrease in estimated negative forcing (aerosols), combined with the stubborn refusal of the planet to warm as had been predicted over the last decade, all makes a high climate sensitivity increasingly untenable.

Conversely, if «climate sensitivity» for a doubling of CO2 is based on recent measurements and CO rates, and past natural variability is underestimated — as you've shown here — then this implies our estimates of sensitivity per CO2 doubling is too high, not too low.

What's new is that several recent papers have offered best estimates for climate sensitivity that are below four degrees Fahrenheit, rather than the previous best estimate of just above five degrees, and they have also suggested that the highest estimates are pretty implausible.

Even with almost no chance of the high end of climate sensitivity estimates being right, the odds of substantial, prolonged and disruptive climate change (and changes in ocean chemistry) are still plenty high enough to justify a sustained push toward an energy menu that works for the long haul.

That would be the General Fluid Dynamics Laboratory which produced the lower «climate sensitivity» range, (Manabe) which was «averaged» with the much higher GISS estimate to produce a high end estimate that was assumed to be real science, when it was actually an average of WAGs.

Using the IPCC climate sensitivity of 3.2 C, the CO2 level by 2100 would need to double by 2100, from today's 392 to 784 ppmv, to reach this warming (the high side IPCC «scenario and storyline» A2 is at this level, with estimated warming of 3.4 C above the 1980 - 1999 average, or ~ 3.2 C above today's temperature).

It appears that the Hansen Scenario B performed fairly well, with an overestimated trend consistent with its estimate of climate sensitivity at what is now considered to be toward the high end of the likely range (although of course, Hansen continues to estimate climate sensitivity at higher levels than most other observers).

(1) climate sensitivity estimates ignore higher estimates; (2) damage estimates at low - temp increases (2.5 C) are off; (3) damage estimates at high - temp increases (10C to 20C) are just silly.

The original paper reports a climate sensitivity range with a lower 90 % CI boundary of 1.6 K, a median of 6.1 K, and a modal value of 2.1, putting it on the higher side of climate sensitivity estimates (Fig. 2 above).

James Annan, of Frontier Research For Global Change, a prominent «warmist», recently said high estimates for climate sensitivity now look «increasingly untenable», with the true figure likely to be about half of the IPCC prediction in its last report in 2007.

Most climate scientists agree those data are seriously deficient and IPCC's estimate for climate sensitivity to CO2 is too high.

Climate sensitivity estimates using climate models support the higher end of the IPCC's likelyClimate sensitivity estimates using climate models support the higher end of the IPCC's likelyclimate models support the higher end of the IPCC's likely range.

In fact, most global warming catastrophists believe the climate sensitivity is at least 3ºC per doubling, and many use estimates as high as 5ºC or 6ºC.

Along with the corrected value of F2xCO2 being higher than the one used in the paper, and the correct comparison being with the model's effective climate sensitivity of ~ 2.0 C, this results in a higher estimate of equilibrium efficacy from Historical total forcing.

Gavin's refusal to admit the extreme LU efficacy comes down to accepting one very dubious run, a run which is a clear statistical outlier, goes to the heart of the problem with Marvel et al: the authors got results they «liked» (lower efficacy for many forcings implies higher climate sensitivity... casting doubt on lower empirical estimates), and so failed to critically examine if their results might have errors.

Think about it — if the various estimates of climate sensitivity based on the instrumental period still had such fat tails just five years ago, then why would an extra five years suddenly turn that around and allow calculations of sensitivity based on the instrumental period to now rule out high sensitivities?

I personally think it is very likely because he used a climate sensitivity estimate that was high by a factor of 2 or more.

As I stated above, with the confines of the narrow way that the IPCC frames the climate change problem, the evidence is growing that we can chop off the fat tail of previous high sensitivity estimates.

If the model Curry and colleagues discussed had incorporated the latest ocean heat content data, their relatively low best estimate for climate sensitivity would have been more in line with previously reported, higher estimates.

To expand slightly on the change in focus to TCR by Gregory and Foster (2008), if one uses a conservatively high figure for the TCR / Climate Sensitivity ratio of 0.7, their updated estimates translate into a climate sensitivity range of about 1.9 — 3.3 C per CO2 doClimate Sensitivity ratio of 0.7, their updated estimates translate into a climate sensitivity range of about 1.9 — 3.3 C per COSensitivity ratio of 0.7, their updated estimates translate into a climate sensitivity range of about 1.9 — 3.3 C per CO2 doclimate sensitivity range of about 1.9 — 3.3 C per COsensitivity range of about 1.9 — 3.3 C per CO2 doubling.

The results open the possibility that recent climate sensitivity estimates from global observations and [intermediate complexity models] are systematically considerably lower or higher than the truth, since they are typically based on the same realization of climate variability.»

It is worth noting that inferences of climate sensitivity from energy budget estimates suggest low ECS values, i.e., ~ 2 K, but their uncertainty is so large that they can not exclude much higher ECS (Forster 2016).

Merging realistic estimates of low - cloud amount, high - cloud amount, and extratropical optical depth feedbacks would likely increase our confidence in constraints on climate sensitivity from climate models.

Instead, the report argues that this approach provides the only reliable method for estimating climate sensitivity, and that all other methods that produce higher estimates (e.g. paleoclimate and GCMs) are wrong.

When consumers see that an observational approach consistently provides a low climate sensitivity and computer models provide a consistently high estimate, they will be enlightened.

Energy balance climate sensitivity estimates are likely biased high due to the failure to account for the natural millennium cycle that is so obvious in the climate record, and the urban heat island effect.

This «climate sensitivity» estimate has emerged as a key climate question, with estimates ranging from a low of about 2.7 °F (1.5 °C) to highs of more than 8 °F (4.5 °C) of warming in this century.

We need remember, however, that to ascribe any significant fraction of the documented warming since 1850 to the Sun requires high estimates of climate sensitivity.

James: The fact that you believe that the high - end estimates of climate sensitivity are very unlikely is now a «Breaking...» story over in Wattsland: http://wattsupwiththat.com/2013/02/01/encouraging-admission-of-lower-climate-sensitivity-by-a-hockey-team-scientist I have submitted a comment there pointing out in essence that this story actually broke about 7 years ago.

«In the Pliocene and Pleistocene, there appears to have been strong coupling between climate and pCO2 changes; there is a wide range of Earth System sensitivity values, all of which exceed or are at the high end of Charney and Earth System sensitivity estimates derived from climate models.

Estimates of climate sensitivity, which should be high if positive feedbacks are strong, are instead getting lower and lower.

The official climate Team says that water vapor feedback has a net positive effect, which is why they estimate the sensitivity of doubling CO2 as high as they do, +2 ºC to +5 ºC.

BBD wrote: «Implying or stating that the slow - down in warming is evidence that AGW is «refuted» or the more nuanced version that it shows that the climate sensitivity estimate is too high is misrepresentation.»

Implying or stating that the slow - down in warming is evidence that AGW is «refuted» or the more nuanced version that it shows that the climate sensitivity estimate is too high is misrepresentation.