Sentences with phrase «data on their climate sensitivity»

Not exact matches

«Based on the satellite data gathered, we can identify areas that, over the past 14 years, have shown high sensitivity to climate variability,» says researcher Alistair Seddon at the Department of Biology at the University of Bergen (UiB).

The data is only 33 years in length, but based on that data, there is no first order correlation between temperature and CO2 during its 33 year period and this suggests that then signal to CO2 (ie., Climate Sensitivity) is so low that it can not be measured within the sensitivity, resolution and errors of our best current temperature meSensitivity) is so low that it can not be measured within the sensitivity, resolution and errors of our best current temperature mesensitivity, resolution and errors of our best current temperature measurements.

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

A 2008 study led by James Hansen found that climate sensitivity to «fast feedback processes» is 3 °C, but when accounting for longer - term feedbacks (such as ice sheet disintegration, vegetation migration, and greenhouse gas release from soils, tundra or ocean), if atmospheric CO2 remains at the doubled level, the sensitivity increases to 6 °C based on paleoclimatic (historical climate) data.

But to reiterate: the difference between climate sensitivity estimates based on land vs. ocean data indicates that something is seriously wrong, either with the model, or the data, or some of both.

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 LGClimate Sensitivity) lists 13 studies (Table 9.3) that constrain climate sensitivity using various types of data, including two usinSensitivity) lists 13 studies (Table 9.3) that constrain climate sensitivity using various types of data, including two using LGclimate sensitivity using various types of data, including two usinsensitivity using various types of data, including two using LGM data.

The Schmittner et al. analysis marks the insensitive end of the spectrum of climate sensitivity estimates based on LGM data, in large measure because it used a data set and a weighting that may well be biased toward insufficient cooling.

I am a coauthor on a manuscript in revision, Olson et al., JGR - Atmospheres (2011), which has a climate sensitivity analysis from modern (historical instrumental) data, using a similar UVic perturbed - physics ensemble approach.

Because this climate sensitivity is derived from empirical data on how Earth responded to past changes of boundary conditions, including atmospheric composition, our conclusions about limits on fossil fuel emissions can be regarded as largely independent of climate models.

The warming effect of CO2 on climate is physically well - understood, and the sensitivity of global temperature to CO2 is independently confirmed by paleoclimatic data, see e.g. Rohling et al. 2012 or the brand - new paper by Friedrich et al. 2016 (here is a nice write - up on this paper from Peter Hannam in the Sydney Morning Herald).

This is of particular interest in relation to «effective climate sensitivity» estimates that rely heavily on OHC uptake data.

This is similar to how the denier claims of no global warming, or of no anthropogenic influence upon warming, or of low climate sensitivity, depend on all observational data being wrong in the same direction.

This kind of forecast doesn't depend too much on the models at all — it is mainly related to the climate sensitivity which can be constrained independently of the models (i.e. via paleo - climate data), moderated by the thermal inertia of the oceans and assuming the (very likely) continuation of CO2 emissions at present or accelerated rates.

In particular, Annan and Hargreaves (2006) used a Bayesian statistical approach that combines information from both 20th century observations and from last glacial maximum data to produce an estimate of climate sensitivity that is much better constrained than by either set of observations alone (see our post on this, here).

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.

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.

I have defined on Climate Audit a non-biased sensitivity analysis of the Yamal CRU data for Steve McIntyre:

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

But I would suppose that equilibrium climate sensitivity [background] and even global mean surface temperature on a decadal scale could be better nailed down by model pruning and better ocean data.

Finally, note that the effect of the last few years of data is smaller on the transient climate response than on climate sensitivity.

A series of sensitivity tests show that our detection results are robust to observational data coverage change, interpolation methods, influence of natural climate variability on observations, and different model sampling (see Supplementary Information).

As well as your objections, the number 5.35 is based on the hypothetical numbers derived from the estimations of climate sensitivity and the output of non-validated models, and have absolutely no meaning whatsoever, since there is no empirical data to support them.

In this work, we use a standard linear definition of climate sensitivity, which we state here, and go on to show how it can be derived from observational data.»

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

So once again, can anyone supply me with a reference in the peer reviewed literature of a numeric value for climate sensitivity that is based on measured data, and not just estimations and the output of non-validated models?

That finding, supported by Forest 2006 Fig.S.7, means that the SFZ 2008 surface model data on their own provide very little discrimination against high climate sensitivity, unlike the CSF 2005 data.

If the methodology used to derive the so called «Climate Sensitivity» was valid, then it would be independent on the set of data used, as long as the size of the domain is greater then zero.

«Skeptical» claims that that discrepancy can only arise from a difference in climate sensitivity are shown, therefore, to be far from skeptical, and to merely read into data the conclusions they wish to find rather than analyze the data on its merits.

After a careful reassessment of climate sensitivity and climate history data, NASA climate science chief James Hansen and his colleagues concluded that the tipping point at which substantial ice - sheets on Earth will disappear is around 450ppm (+ / -100 ppm) of CO2.

If climate sensitivity is a variable and not a constant what can we really learn from paleo data other than what the climate sensitivity was, on average, over an extended period of time?

Our key observation, ignoring climate models and focusing on climate data, is that CO2 climate sensitivity has been far overstated by the IPCC and its disciples, primarily because of their misguided allegiance to un-validated computer models that engineers dealing with public safety issues would completely ignore.

Until warmists admit to the obvious empirical data that proves that climate sensitivity has never been measured, we will go on having these fruitless discussions.

Italian flag analysis: 30 % Green, 50 % White, 20 % Red (JC Note: all climate models produce this result in spite of different sensitivities and using different forcing data sets; the models do not agree on the causes of the early 20th century warming and the mid-century cooling and do not reproduce the mid-century cooling.)

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].

It aims to provide a review of the literature on crop pollination, with a focus on the effects of climate change on pollinators important for global crop production, and to present an overview of available data on the temperature sensitivity of crop pollinators and entomophilous crops.

The frontpage implies that climate science to date has not been «real,» while the many errors made by the speakers as well as their serious credibility issues (Willie Soon's infamous paper, another paper more recently with Noah Robinson that made up data, Spencer's flawed book on climate sensitivity, Singer's history since about 1990, Schmitt's uncorrected error in a NASA paper, Bast and Taylor's lies in defense of Schmitt, and so on) suggest the opposite — the speakers at the ICCC are the ones attempting to falsify the science.

Based on observational data climate sensitivity is clearly rather small and much smaller that the majority of models.»

Using your definition of what «empirical» means, where is the empirical data that proves that the climate sensitivity for a doubling of CO2, caused by a change on radiative forcing of abouit 3.7 Wm - 2, is any particular number you like to claim?

«Lewis & Crok perform their own evaluation of climate sensitivity, placing more weight on studies using «observational data» than estimates of climate sensitivity based on climate model analysis.»

While Alley «interprets» reconstructed data series from selected periods of our geological past to try to prove his «control knob» hypothesis (and a 2xCO2 climate sensitivity of 3 °C) the Lacis et al. paper relies on model simulations (hey, Gavin Schmidt is one of the co-authors).

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»

As we discussed regarding the Norwegian paper, studies estimating climate sensitivity based on recent data may be biased low due to a failure to account for increased heat transfer to the 700 — 2000 meter ocean layer (Figure 3).

As for the LGM, equilibrium climate sensitivity estimates depend strongly on the temperature data used.

manacker / max You write «Past predictions of 2xCO2 climate sensitivity at equilibrium (ECS) have been made based on model simulations, rather than on analyses of real - time data».

For a complete discussion of this and an updated forecast of the possible coming cooling based on the natural 1000 year and 60 year periodicities in the temperature data see http://climatesense.norpag.blogspot.com As to climate sensitivity we have no good ideas of what it is -.

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.

I think that climate blogs have rather argued that recent data are just natural variability, and thus don't have any effect on long - term trends nor sensitivity.

Past predictions of 2xCO2 climate sensitivity at equilibrium (ECS) have been made based on model simulations, rather than on analyses of real - time data.

In his House of Commons presentation, toward the end, he gives a sketch of an alternative derivation of the «Climate Sensitivity» based on observed rates of evaporation increase per change in sea surface temperature, and this based on data from the 2007 paper by Wentz et.

In most cases, these range from about 2 to 4.5 C per doubled CO2 within the context of our current climate — with a most likely value between 2 and 3 C. On the other hand, chapter 9 describes attempts ranging far back into paleoclimatology to relate forcings to temperature change, sometimes directly (with all the attendant uncertainties), and more often by adjusting model parameters to determine the climate sensitivity ranges that allow the models to best simulate data from the past — e.g., the Last Glacial Maximum (LGM).