Sentences with phrase «lower estimate of climate sensitivity»

The implications are still that a lower estimate of climate sensitivity means «there is a reason to act».

In a 2013 blog post, Chris Hope of Cambridge University and a leading climate - economics modeler showed how lower estimates of climate sensitivity affected the SCC.

We already looked at how climate skeptics rely on a selective reading of the literature to highlight low estimates of climate sensitivity and use the divergence between climate models and measured temperatures to make conjectural statements about climate models being too sensitive to CO2, without considering other factors that could account for such divergence.

However as we document in the Lewis / Crok report, the IPCC was well aware of these recently published lower estimates of climate sensitivity.

On the other hand the projected positive feedbacks you support, which are COMPLETELY theoretical, depend on the LEAST understood aspects of the affect of water vapor and cloud formation, so the strong feedbacks PROJECTED are the least dependable, while the «OBSERVATIONS» used by Lindzen, Spencer, and others, support the lower estimates of climate sensitivity.

The low estimates of climate sensitivity by Chylek and Lohmann (2008) and Schmittner et al. (2011), ~ 2 °C for doubled CO2, are due in part to their inclusion of natural aerosol change as a climate forcing rather than as a fast feedback (as well as the small LGM - Holocene temperature change employed by Schmittner et al., 2011).»

The relatively slow rate of warming over the past decade has lowered some estimates of climate sensitivity based on surface temperature records.

Second, it is the among the lowest estimates of climate sensitivity among actively publishing climate researchers.

If the recent lower estimates of climate sensitivity are correct and emissions follow a relatively low path, warming will likely be modest and its effects mild.

Not exact matches

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.»

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.

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

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.

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.

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.

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.

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.

There has been an unusual surge of interest in the climate sensitivity based on the last decade's worth of temperature measurements, and a lengthy story in the Economist tries to argue that the climate sensitivity may be lower than previously estimated.

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.

(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.

The obvious answer (from someone who is indeed receptive to arguments for lower - than - consensus climate sensitivities) is that it was on a par with recent hot years because temperatures at US latitudes of the globe really weren't as much cooler in the 1930s / 1940s (compared to the present) than GISS / Hadley's best estimates (from often sketchy global coverage) suggest.

These results suggest that sea surface temperature pattern - induced low cloud anomalies could have contributed to the period of reduced warming between 1998 and 2013, and offer a physical explanation of why climate sensitivities estimated from recently observed trends are probably biased low 4.

David's comments reminded me of something that Suki Manabe and I wrote more than 25 years ago in a paper that used CLIMAP data in a comparative evaluation of two versions of the 1980s - vintage GFDL model: «Until this disparity in the estimates of LGM paleoclimate is resolved, it is difficult to use data from the LGM to evaluate differences in low latitude sensitivity between climate models.»

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 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.

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.

Hegerl et al (2006) for example used comparisons during the pre-industrial of EBM simulations and proxy temperature reconstructions based entirely or partially on tree - ring data to estimate the equilibrium 2xCO2 climate sensitivity, arguing for a substantially lower 5 % -95 % range of 1.5 — 6.2 C than found in several previous studies.

A lower and more constrained estimate of climate sensitivity using updated observations and detailed radiative forcing time series, In review in Journal of Cclimate sensitivity using updated observations and detailed radiative forcing time series, In review in Journal of ClimateClimate.

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.

Now comes a new entry in the effort to specify the value known as «climate sensitivity,» and it falls on the low side of the existing estimates.

The innocent layperson may have thought that looming climate change damages would be enough, but that isn't the case for the lower range of sensitivity estimates, again as EPA's own table shows.

I tend to believe that including the recent years will, indeed, lower the best estimate of climate sensitivity and, hopefully, allow for a more reliable upper limit.

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.

Likewise, when climate sensitivity is low, emissions drive less temperature change and cause less damage, leading to lower estimates of the SCC.

A lower and more constrained estimate of climate sensitivity using updated observations and detailed radiative forcing time series R. B. Skeie (1), T. Berntsen (1,2), M. Aldrin (3), M. Holden (3), and G. Myhre (1)(1) Center for International Climate and Environmental Research — Oslo (CICERO), Norway ([email protected]), (2) Department of Geosciences, University of Oslo, Norway, (3) Norwegian Computing Center, Oslo, Norway A key question in climate science is to quantify the sensitivity of the climate system to perturbation in the radiative forcinclimate sensitivity using updated observations and detailed radiative forcing time series R. B. Skeie (1), T. Berntsen (1,2), M. Aldrin (3), M. Holden (3), and G. Myhre (1)(1) Center for International Climate and Environmental Research — Oslo (CICERO), Norway ([email protected]), (2) Department of Geosciences, University of Oslo, Norway, (3) Norwegian Computing Center, Oslo, Norway A key question in climate science is to quantify the sensitivity of the climate system to perturbation in the radiative forcinClimate and Environmental Research — Oslo (CICERO), Norway ([email protected]), (2) Department of Geosciences, University of Oslo, Norway, (3) Norwegian Computing Center, Oslo, Norway A key question in climate science is to quantify the sensitivity of the climate system to perturbation in the radiative forcinclimate science is to quantify the sensitivity of the climate system to perturbation in the radiative forcinclimate system to perturbation in the radiative forcing (RF).

This Nature Climate Change paper concluded, based purely on simulations by the GISS - E2 - R climate model, that estimates of the transient climate response (TCR) and equilibrium climate sensitivity (ECS) based on observations over the historical period (~ 1850 to recent times) were biasClimate Change paper concluded, based purely on simulations by the GISS - E2 - R climate model, that estimates of the transient climate response (TCR) and equilibrium climate sensitivity (ECS) based on observations over the historical period (~ 1850 to recent times) were biasclimate model, that estimates of the transient climate response (TCR) and equilibrium climate sensitivity (ECS) based on observations over the historical period (~ 1850 to recent times) were biasclimate response (TCR) and equilibrium climate sensitivity (ECS) based on observations over the historical period (~ 1850 to recent times) were biasclimate sensitivity (ECS) based on observations over the historical period (~ 1850 to recent times) were biased low.

Anyone reading our paper may or may not agree with our choice of parameters and hence with our revised estimates of climate sensitivity, which are very much lower and very much closer to observed reality than those of the more complex models.

Would the lower rate of cooling give us something close to an empirical estimate of climate sensitivity to increased CO2?

These values have been estimated using relatively simple climate models (one low - resolution AOGCM and several EMICs based on the best estimate of 3 °C climate sensitivity) and do not include contributions from melting ice sheets, glaciers and ice caps.

The right - hand panel shows ranges of global average temperature change above pre-industrial, using (i) «best estimate» climate sensitivity of 3 °C (black line in middle of shaded area), (ii) upper bound of likely range of climate sensitivity of 4.5 °C (red line at top of shaded area)(iii) lower bound of likely range of climate sensitivity of 2 °C (blue line at bottom of shaded area).

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.

This in the comments to an article about how recent data is forcing lowering of estimated climate sensitivity to doubling of CO2.

However, because climate scientists at the time believed a doubling of atmospheric CO2 would cause a larger global heat imbalance than today's estimates, the actual climate sensitivities were approximatly 18 % lower (for example, the «Best» model sensitivity was actually closer to 2.1 °C for doubled CO2).

Assuming the same climate sensitivity, Lindzen's estimate of a 2.5 °C drop for a -30 W / m2 forcing would imply that currently doubling CO2 would warm the planet by only a third of a degree at equilibrium, which is well outside the bounds of IPCC estimates and even very low by most skeptical standards.

(i) You seem unaware of the fact that this was only Arrhenius's first estimate, and that he himself subsequently estimated climate sensitivity to be more than 3 times lower.

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).

There appear to be upwards of 15 estimates below 1.5 C. Incorporating the numerous lower climate sensitivity estimates would need to rephrase to something like: «Climate sensitivity is likely to be in the range 0.5 °C to 4 °C with a best estimate of 0.6 °C for measurements and 3 °C for climate sensitivity estimates would need to rephrase to something like: «Climate sensitivity is likely to be in the range 0.5 °C to 4 °C with a best estimate of 0.6 °C for measurements and 3 °C for Climate sensitivity is likely to be in the range 0.5 °C to 4 °C with a best estimate of 0.6 °C for measurements and 3 °C for models.

Because of the many uncertainties involved, any estimate of climate sensitivity comes with a range, a lower and upper limit within which the real value could reasonably lie.

But arguments over the precise value of climate sensitivity duck the wider point, which is that even if we're lucky and climate sensitivity is on the low side of scientists» estimates, we're still heading for a substantial level of warming by the end of the century if greenhouse gas emissions aren't addressed, as the IPCC has highlighted.