Sentences with phrase «constraints on climate sensitivity»

The glacial / interglacial cycle is one of the stronger constraints on climate sensitivity, and so on CO2 sensitivity.

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.

This issue is of vital importance when discussing observational constraints on climate sensitivity, since the natural changes we observe — due to ENSO, AMO, volcanoes — do not all share the same horizontal structure as the forced response to CO2.

Read more «Constraints on Climate Sensitivity From Space - Based Measurements of Low - Cloud Reflection»»

Data - based evidence on radiative forcing and constraints on climate sensitivity, Quaternary Science Reviews 2010.

Having better constraints on the timing and magnitude of past climate changes should ultimately lead to better constraints on climate sensitivity and the role of natural variability in the climate system.

Therefore, unless those uncertainties are reduced, the constraints on climate sensitivity from the 20th Century will not be useful.

We contended here before that this is a bit of a leap, since there are other constraints on climate sensitivity (such as the last ice age) and other sources of uncertainty (solar, ozone, land use, etc.).

You can spend as much time as you like explaining the basis of the paleo - climate constraints on climate sensitivity, only to have the next comment claim that it's tiny based on an unpublished back - of - the - agenda calculation he read online.

There is a new paper on Science Express that examines the constraints on climate sensitivity from looking at the last glacial maximum (LGM), around 21,000 years ago (Schmittner et al, 2011)(SEA).

There is a new paper on Science Express that examines the constraints on climate sensitivity from looking at the last glacial maximum (LGM), around 21,000 years ago (Schmittner et al, 2011)(SEA).

The IPCC AR4 (9.6: Observational Constraints on Climate Sensitivity) lists 13 studies (Table 9.3) that constrain climate sensitivity using various types of data, including two using LGM data.

Radiative forcing is not a zero - sum game in the sense you laid it out, but it is fairly standard practice to use the observed temperature record to put some constraints on both climate sensitivity and the magnitude of unknown forcing.

There is an Aldrin et al paper, published some time ago — which gave a decent constraint on climate sensitivity, though nothing particularly surprising or interesting IMO.

If the current instrumental record is a very poor constraint on climate sensitivity — which Figure 2 suggests is the case — then it's entirely possible for the additional decade of temperature data to have no effect whatsoever on estimates of sensitivity.

Ironically, it is exactly because aerosol forcing is so uncertain and because the climate hasn't equilibrated yet that the observed warming since pre-industrial times is only a very weak constraint on climate sensitivity.

Not exact matches

We have discussed climate sensitivity frequently in previous posts and we have often referred to the constraints on its range that can be derived from paleo - climates, particularly the last glacial maximum (LGM).

The tight constraint on the lower limit of climate sensitivity indicates we're looking down the barrel of significant warming in future decades.

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.

There are two recent papers on paleo constraints: the already mentioned PALAEOSENS (2012) paper which gives a good survey of existing estimates from paleo - climate and the hierarchy of different definitions of sensitivity.

In Part 1 of this article the nature and validity of emergent constraints [1] on equilibrium climate sensitivity (ECS) in GCMs were discussed, drawing mainly on the analysis and assessment of 19 such constraints in Caldwell et al. (2018), [2] who concluded that only four of them were credible.

In Part 1 of this article the nature and validity of emergent constraints [i] on equilibrium climate sensitivity (ECS) in GCMs were discussed, drawing mainly on the analysis and assessment of 19 such constraints in Caldwell et al (2018; henceforth Caldwell), [ii] who concluded that only four of them were credible.

There are three main methodologies that have been used in the literature to constrain sensitivity: The first is to focus on a time in the past when the climate was different and in quasi-equilibrium, and estimate the relationship between the relevant forcings and temperature response (paleo constraints).

We have discussed climate sensitivity frequently in previous posts and we have often referred to the constraints on its range that can be derived from paleo - climates, particularly the last glacial maximum (LGM).

As you say in a previous post on sensitivity... «There are three main methodologies that have been used in the literature to constrain sensitivity: The first is to focus on a time in the past when the climate was different and in quasi-equilibrium, and ESTIMATE the relationship between the relevant forcings and temperature response (paleo constraints).

They show that this places a strong constraint on our ability to determine a specific «true» value of climate sensitivity, S.

There are three main methodologies that have been used in the literature to constrain sensitivity: The first is to focus on a time in the past when the climate was different and in quasi-equilibrium, and estimate the relationship between the relevant forcings and temperature response (paleo constraints).

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.

«Observational Constraints on Mixed - Phase Clouds Imply Higher Climate Sensitivity.»

However, if those sensitivity tests confirm the inter-model relationship (green arrow in Figure 1), the credibility of assumed physical mechanisms and observational constraints on climate change projections increases.

[19] Lewis, «An Objective Bayesian Improved Approach for Applying Optimal Fingerprint Techniques to Estimate Climate Sensitivity,» and Otto et al., «Energy Budget Constraints on Climate Response.»

That LOD is a hard constraint on «climate sensitivity» (though maybe not that sensitive.)

We suggest that the best constraint on actual climate sensitivity is provided by paleoclimate data that imply a sensitivity 3 ± 1 °C for 2 CO2 [Hansen et al., 1984, 1993, 1997b; Hoffert and Covey, 1992].

The IPCC tries to overcome this actually insuperable Lorenz constraint on modelling by estimating climate sensitivity via a probability - density function.

This data seems to suggest modern warming stronger than that seen in the medieval periods displayed (see figure 2): «Ensemble reconstruction constraints on the global carbon cycle sensitivity to climate»

The sensitivity he then derives is projected back using the 0.8 deg C warming over the 20th C. However, this is ludicrous — the sensitivity in the recent period can't be more than say, 1 ppmv per 0.1 deg C. Projected back you would have say a 10 ppmv (max) change over the 20th C. Paleo - climate constraints demonstrate that CC feedback even on really long time scales is not more than 100 ppmv / 6 deg C (i.e. 16 ppmv / deg C), and over shorter time periods (i.e. Frank et al, 2010) it is more like 10 ppmv / deg C. Salby's sensitivity appears to be 10 times too large.

Gavin writes «Paleo - climate constraints demonstrate that CC feedback even on really long time scales is not more than 100 ppmv / 6 deg C (i.e. 16 ppmv / deg C), and over shorter time periods (i.e. Frank et al, 2010) it is more like 10 ppmv / deg C. Salby's sensitivity appears to be 10 times too large.»

These new constraints on Phanerozoic ca will greatly assist in establishing benchmarks for Earth system sensitivity to CO2 (also known as «slow - feedback» or «long - term» climate sensitivity).

Evaluating Emergent Constraints on Equilibrium Climate Sensitivity.

In Part 1 of this article the nature and validity of emergent constraints [1] on equilibrium climate sensitivity (ECS) in GCMs were discussed, drawing mainly on the analysis and assessment of 19 such constraints in Caldwell et al. (2018), [2] who concluded that only four of them were credible.

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.

[16] Qu, X., A. Hall, A. M. DeAngelis, M. D. Zelinka, S. A. Klein, H. Su, B. Tian, and C. Zhai, 2018: On the emergent constraints of climate sensitivity.

Part 1 of this article the nature and validity of emergent constraints [1] on equilibrium climate sensitivity (ECS) in GCMs were discussed, drawing mainly on the analysis and assessment of 19 such constraints in Caldwell et al. (2018), [2] who concluded that only four of them were credible.

[17] Cox, P. M., C. Huntingford, and M. S. Williamson, 2018: Emergent constraint on equilibrium climate sensitivity from global temperature variability.