Sentences with phrase «in model climate sensitivity»

Sherwood, S.C., S. Bony and J.L Dufresne, 2014: Spread in model climate sensitivity traced to atmospheric convective mixing.

Spread in model climate sensitivity traced to atmospheric convective mixing.

Uncertainty in model climate sensitivity traced to representations of cumulus precipitation microphysics.

This SAP report attributes the variation in model climate sensitivity to variations in assumed sulphate forcing rather than clouds, and Lindzen doesn't seem to be associated with it: http://downloads.climatescience.gov/sap/sap2-3/sap2-3-final-report-all.pdf

See Spread in model climate sensitivity traced to atmospheric convective mixing (doi: 10.1038 / nature12829).

But the sentence reading «Spread in model climate sensitivity is a major factor contributing to the range in projections of future climate changes,» strongly suggests it is an input.

«Climate sensitivity is a metric used to characterise the response of the global climate system to a given forcing» and «'' Spread in model climate sensitivity is a major factor contributing to the range in projections of future climate changes» both suggest to me that CS is an input.

-LSB-...] Study paper Spread in model climate sensitivity traced to atmospheric convective mixing Climate Sensitivity in the Anthropocene «Worst» of Climate Predictions Are the Most Likely: New -LSB-...]

«Spread in Model Climate Sensitivity Traced to Atmospheric Convective Mixing.»

That's clear from recent peer - reviewed reports such as Marvel et al 2016: Implications for climate sensitivity from the response to individual forcings, and Sherwood et al. 2014: Spread in model climate sensitivity traced to atmospheric convective mixing.

Not exact matches

The study also explains why climate models usually simulate a lower sensitivity than can be detected in observations.

They used two different climate models, each with a different sensitivity to carbon dioxide, to project California's future under two scenarios: an optimistic one, in which we only double the level of carbon dioxide in the atmosphere — since the 19th century we've already increased it by about a third — and a pessimistic scenario, in which we more than triple CO2.

At the same time, new studies of climate sensitivity — the amount of warming expected for a doubling of carbon dioxide levels from 0.03 to 0.06 percent in the atmosphere — have suggested that most models are too sensitive.

A 2000 - year transient climate simulation with the Community Climate System Model shows the same temperature sensitivity to changes in insolation as does our proxy reconstruction, supporting the inference that this long - term trend was caused by the steady orbitally driven reduction in summer insoclimate simulation with the Community Climate System Model shows the same temperature sensitivity to changes in insolation as does our proxy reconstruction, supporting the inference that this long - term trend was caused by the steady orbitally driven reduction in summer insoClimate System Model shows the same temperature sensitivity to changes in insolation as does our proxy reconstruction, supporting the inference that this long - term trend was caused by the steady orbitally driven reduction in summer insolation.

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.

The models that were least accurate also had the lowest climate sensitivity baked in, the scientists said.

That uncertainty is represented in the latest crop of global climate models, which assume a climate sensitivity of anywhere from about 3 to 8 degrees F.

Isaac Held, a National Oceanic and Atmospheric Administration climate scientist, said he agreed with the researchers about the «the importance of getting the ice - liquid ratio in mixed - phase clouds right,» but he doesn't agree that global climate models generally underestimate climate sensitivity.

The group hopes other scientists will conduct similar experiments using different models to help hone in on a more reliable measure of climate sensitivity.

«When the processes are correct in the climate models the level of climate sensitivity is far higher.

On the face of it the range of the IPCC models is centrally within the A&H 90 % range, but visual inspection of Figure 1 suggests that A&H find that there is about a 45 % probability that climate sensitivity is below the lower end of the range quoted by Meehl in August 2004 (Of course the IPCC draft report, which I have not seen, may include models with lower sensitivity than 2.6 ºC).

As we explain in our glossary item, climatologists use the concept of radiative forcing and climate sensitivity because it provides a very robust predictive tool for knowing what model results will be, given a change of forcing.

We show elsewhere (8) that a forcing of 1.08 W / m2 yields a warming of 3/4 °C by 2050 in transient climate simulations with a model having equilibrium sensitivity of 3/4 °C per W / m2.

Where climate sensitivity is estimated in studies involving comparing observations with values simulated by a forced climate model at varying parameter settings (see Appendix 9.

Themes: Aerosols, Arctic and Antarctic climate, Atmospheric Science, Climate modelling, Climate sensitivity, Extreme events, Global warming, Greenhouse gases, Mitigation of Climate Change, Present - day observations, Oceans, Paleo - climate, Responses to common contrarian arguments, The Practice of Science, Solar forcing, Projections of future climate, Climate in the media, Meeting Reports, Miscellclimate, Atmospheric Science, Climate modelling, Climate sensitivity, Extreme events, Global warming, Greenhouse gases, Mitigation of Climate Change, Present - day observations, Oceans, Paleo - climate, Responses to common contrarian arguments, The Practice of Science, Solar forcing, Projections of future climate, Climate in the media, Meeting Reports, MiscellClimate modelling, Climate sensitivity, Extreme events, Global warming, Greenhouse gases, Mitigation of Climate Change, Present - day observations, Oceans, Paleo - climate, Responses to common contrarian arguments, The Practice of Science, Solar forcing, Projections of future climate, Climate in the media, Meeting Reports, MiscellClimate sensitivity, Extreme events, Global warming, Greenhouse gases, Mitigation of Climate Change, Present - day observations, Oceans, Paleo - climate, Responses to common contrarian arguments, The Practice of Science, Solar forcing, Projections of future climate, Climate in the media, Meeting Reports, MiscellClimate Change, Present - day observations, Oceans, Paleo - climate, Responses to common contrarian arguments, The Practice of Science, Solar forcing, Projections of future climate, Climate in the media, Meeting Reports, Miscellclimate, Responses to common contrarian arguments, The Practice of Science, Solar forcing, Projections of future climate, Climate in the media, Meeting Reports, Miscellclimate, Climate in the media, Meeting Reports, MiscellClimate in the media, Meeting Reports, Miscellaneous.

Hi, I don't mean to turn this into yet another sceptic thread, but I've read in another site that there apparently are doubts about current models assuming that climate sensitivity is constant.

The climate sensitivity is an output of complex models (it is not decided ahead of time) and it doesn't help as much with the details of the response (i.e. regional patterns or changes in variance), but it's still quite useful for many broad brush responses.

In addition, past data can be used to provide independent estimates of climate sensitivity, which provide a reality check on the models.

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.

However, there are lots of disagreements discussed here — in regard to climate sensitivity, hurricanes, aerosols, climate modelling etc. but most of these are serious discussions amongst people who are genuinely trying to come to an answer.

Stowasser, M., K. Hamilton, and G.J. Boer, 2006: Local and global climate feedbacks in models with differing climate sensitivity.

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.

Therefore, I wouldn't attach much credence, if any, to a modelling study that didn't explore the range of possibilities arising from such uncertainty in parameter values, and particularly in the value of something as crucial as the climate sensitivity parameter, as in this example.

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.

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.

They got 10 pages in Science, which is a lot, but in it they cover radiation balance, 1D and 3D modelling, climate sensitivity, the main feedbacks (water vapour, lapse rate, clouds, ice - and vegetation albedo); solar and volcanic forcing; the uncertainties of aerosol forcings; and ocean heat uptake.

Given that clouds are known to be the primary source of uncertainty in climate sensitivity, how much confidence can you place in a study based on a model that doesn't even attempt to simulate clouds?

So, the key thing in evaluating climate sensitivity is to use the LGM as a test of how well the models are doing clouds, using the LGM, and then see what happens in the same model when you project to the future.

Re Clive Best — there is a range in climate sensitivity among models.

Liu, J., et al., 2003: Sensitivity of sea ice to physical parameterizations in the GISS global climate model.

There have been quite a number of papers published in recent years concerning «emergent constraints» on equilibrium climate sensitivity (ECS) in comprehensive global climate models (GCMs), of both the current (CMIP5) and previous (CMIP3) generations.

However, in view of the fact that cloud feedbacks are the dominant contribution to uncertainty in climate sensitivity, the fact that the energy balance model used by Schmittner et al can not compute changes in cloud radiative forcing is particularly serious.

However, because of the various unknowns in the cloud process, the models give quite different climate sensitivities, accounting for much of the IPCC spread.

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.

They conclude, based on study of CMIP5 model output, that equilibrium climate sensitivity (ECS) is not a fixed quantity — as temperatures increase, the response is nonlinear, with a smaller effective ECS in the first decades of the experiments, increasing over time.

Indeed, Gore could have used the ice core data to make an additional and stronger point, which is that these data provide a nice independent test of climate sensitivity, which gives a result in excellent agreement with results from models.

It is not all that earthshaking that the numbers in Schmittner et al come in a little low: the 2.3 ºC is well within previously accepted uncertainty, and three of the IPCC AR4 models used for future projections have a climate sensitivity of 2.3 ºC or lower, so that the range of IPCC projections already encompasses this possibility.

These models all suggest potentially serious limitations for this kind of study: UVic does not simulate the atmospheric feedbacks that determine climate sensitivity in more realistic models, but rather fixes the atmospheric part of the climate sensitivity as a prescribed model parameter (surface albedo, however, is internally computed).

Lindzen and Giannitsis (2002) pose the hypothesis that the rapid change in tropospheric (850 — 300 hPa) temperatures around 1976 triggered a delayed response in surface temperature that is best modelled with a climate sensitivity of less than 1 °C.

Another way to estimate climate sensitivity from both models AND observations is to calculate the ratio of observed warming to forecast warming... then multiply that by the ECS value used in the model.