Sentences with phrase «of estimates of climate sensitivity»
The wide range of estimates of climate sensitivity is attributable to uncertainties about the magnitude of climate feedbacks (e.g., water vapor, clouds, and albedo).
https://www.yaleclimateconnections.org/
I do enjoy reading the sometimes lively debate surrounding these issues, and I certainly prefer a bit of skepticism to things like a link to a discussion on Scientific American that I followed recently where they were discussing how the recent temperature record has lead to a lowering of estimates of climate sensitivity.
Not exact matches
The authors found that current conservation prioritizations do not correspond to their projected estimates of climate sensitivities.
To estimate how much the sensitivity varies, Gary Russell of the NASA Goddard Institute for Space Studies in New York and colleagues ran a climate model repeatedly.
It tries to turn a major factor in the uncertainty in climate sensitivity estimates — the behavior of clouds — into a strength.
On previous estimates of the climate sensitivity, that is far too late.
This new research takes away the lower end of climate sensitivity estimates, meaning that global average temperatures will increase by 3 °C to 5 °C with a doubling of carbon dioxide.»
When Otto calculated the climate sensitivity from his data, he found it was about 2 °C — with a range of 0.9 to 5 °C — well below the IPCC's best estimate of 3 °C.
By studying the relationship between CO2 levels and climate change during a warmer period in Earth's history, the scientists have been able to estimate how the climate will respond to increasing levels of carbon dioxide, a parameter known as «climate sensitivity».
«Our estimates of climate sensitivity lie well within the range of 1.5 to 4.5 ºC increase per CO2 doubling summarised in the latest IPCC report.
«My view on this is that the research needs to broaden out to have more of a focus on variability more generally so that a) we can predict the next few years better b) we can refine our estimates of the sensitivity of the climate system to increases in greenhouse gas concentrations.»
The IPCC wishes to destroy the world economy and starve the world of energy and food at a cost of $ 76 trillion over the next 40 year's (UN estimate), to keep global temps below 2C, when even their wildly pessimistic and disconfirmed projections (formally known as predictions) now suggest that climate sensitivity could be as low as 1.5 C, without spending a dime.
Well while they are «dialing back» their estimate of «Climate Sensitivity», that legacy of presumably the late Dr Stephen Schneider, they might also consider the claim that: -
In the figure in this article below, 10 out of 17 recent climate sensitivity estimates are 2C or lower (3 IPCC estimates counted as 1): http://www.cato.org/blog/current-wisdom-even-more-low-climate-sensitivity-estimates
We show how the maintained consensus about the quantitative estimate of a central scientific concept in the anthropogenic climate - change field — namely, climate sensitivity — operates as an «anchoring device» in «science for policy».
Olson, R., et al. «What is the effect of unresolved internal climate variability on climate sensitivity estimates?.»
Dr. Benestad states: «They take the ratios of the amplitude of band - passed filtered global temperatures to similarly band - passed filtered solar signal as the estimate for the «climate sensitivity».
They take the ratios of the amplitude of band - passed filtered global temperatures to similarly band - passed filtered solar signal as the estimate for the «climate sensitivity».
That study addressed a puzzle, namely that recent studies using the observed changes in Earth's surface temperature suggested climate sensitivity is likely towards the lower end of the estimated range.
The NGN article itself gives a good explanation of climate sensitivity and the various studies and estimates of it, and does quote Michael Schlesinger of the University of Illinois saying that Hegerl's result «means climate sensitivity is larger than we thought for 30 years, so the problem is worse than we thought.
Therefore studies based on observed warming have underestimated climate sensitivity as they did not account for the greater response to aerosol forcing, and multiple lines of evidence are now consistent in showing that climate sensitivity is in fact very unlikely to be at the low end of the range in recent estimates.
About our estimates of the climate transfer sensitivity to solar variations at 11 years and 22 years, Dr. Benestad makes again a great confusion by misquoting and misunderstanding our paper.
He attacked mainstream estimates of climate sensitivity by a misapplication of the Stefan - Bolzmann equation.
They used some crude estimates of «climate sensitivity» and estimates of Total Solar Irradiance (TSI) to calculate temperature signal (in form of anomalies).
Almost 30 years ago, Jule Charney made the first modern estimate of the range of climate sensitivity to a doubling of CO2.
And that is why they don't report that «climate sensitivity is probably in the middle of previous predictions» and do report «Climate sensitivity may be twice scientists» previous estimate.climate sensitivity is probably in the middle of previous predictions» and do report «Climate sensitivity may be twice scientists» previous estimate.Climate sensitivity may be twice scientists» previous estimate.»
In your sixth last line, you've put the Annan and Hargreaves (A&H) estimate of the lower bound of the 95 % confidence limits for climate sensitivity at 1.9 ºC.
Where (equilibrium / effective) climate sensitivity (S) is the only parameter being estimated, and the estimation method works directly from the observed variables (e.g., by regression, as in Forster and Gregory, 2006, or mean estimation, as in Gregory et al, 2002) over the instrumental period, then the JP for S will be almost of the form 1 / S ^ 2.
In international assessments of the climate issue, the consensus - estimate of 1.5 degrees C to 4.5 degrees C for climate sensitivity has remained unchanged for two decades.
If you want to estimate climate sensitivity to doubling CO2, don't you need to estimate as precisely as possible the direct and indirect effects of each forcing on temperature trends?
My only point on the paper was that the estimates of climate sensitivity therein had been relied upon in the Stern discussion papers.
The calculations of prospective warming in the OXONIA lecture and the accompanying discussion papers are based on the new climate sensitivity estimates by Murphy et al which were published in Nature, 12 August 2004, vol.
In estimating climate sensitivity such effects must be controlled for, and subtracted out to yield the portion of climate change attributable to CO2.
That gives them various estimates of the climate sensitivity.
I agree that the issue of estimating climate sensitivity is conceptually something like «identifying» H from F and T in your formula.
In this commentary, I will discuss the question «If somebody were to discover that climate variations in the past were stronger than previously thought, what would be the implications for estimates of climate sensitivity?»
In addition, past data can be used to provide independent estimates of climate sensitivity, which provide a reality check on the models.
If one accepts Ruddiman's hypothesis, one implicitly agrees that: i) CO2 and CH4 can be affected by human activity, ii) greenhouse gases have a significant forcing role, and iii) climate sensitivity is in the ballpark of mainstream estimates.
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.
«the long fat tail that is characteristic of all recent estimates of climate sensitivity simply disappears, with an upper 95 % probability limit... easily shown to lie close to 4 °C, and certainly well below 6 °C.»
In the end, Archibald concludes that the warming from the next 40 ppm of CO2 rise (never mind the rest of it) will only be 0.04 degrees C. Archibald's low - ball estimate of climate change comes not from the modtran model my server ran for him, but from his own low - ball value of the climate sensitivity.
In fact, scientists have long recognized the importance of solar variability as one of the factors governing climate (see the very scholarly review of the subject by Bard and Frank, available here at EPSL or here as pdf) An understanding of solar variability needs to be (and is) taken into account in attribution of climate change of the past century, and in attempts to estimate climate sensitivity from recent climate variations.
Most of the non-model estimates of climate sensitivity are based on the analyses using other forcings such as solar and aerosols, and the assumption that sensitivity to CO2 will be the same, despite the differences in way these forcings couple to the climate system.
It is important to regard the LGM studies as just one set of points in the cloud yielded by other climate sensitivity estimates, but the LGM has been a frequent target because it was a period for which there is a lot of data from varied sources, climate was significantly different from today, and we have considerable information about the important drivers — like CO2, CH4, ice sheet extent, vegetation changes etc..
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.
I think that some comment on my energy balance based climate sensitivity estimate of 1.6 - 1.7 °C (details at http://www.webcitation.org/6DNLRIeJH), which underpinned Matt Ridley's WSJ op - ed, would have been relevant and of interest.
This is a 0.9 ºC reduction from the sensitivity of 2.5 °C estimated in that predecessor study, which used the same climate model.
«note that what is done with these estimates of climate sensitivity for LGM climate is to use the state of the climate already in place at the LGM — including the ice albedo.»
New paper mixing «climate feedback parameter» with climate sensitivity... «climate feedback parameter was estimated to 5.5 ± 0.6 W m − 2 K − 1» «Another issue to be considered in future work should be that the large value of the climate feedback parameter according to this work disagrees with much of the literature on climate sensitivity (Knutti and Hegerl, 2008; Randall et al., 2007; Huber et al., 2011).
A combination of circumstances makes model - based sensitivity estimates of distant times and different climates hard to do, but at least we are getting a good education about it.