Sentences with phrase «warming simulations with»

In most future global warming simulations with climate models no meltwater from Greenland is included so far.

Not exact matches

By the end of the simulated grand solar minimum, however, the warming in the model with the simulated Maunder Minimum had nearly caught up to the reference simulation.

The second simulation overlaid that same weather data with a «pseudo global warming» technique using an accepted scenario that assumes a 2 - to 3 - degree increase in average temperature, and a doubling of atmospheric carbon dioxide.

Their new analysis is based on a computer simulation of the changes in temperature of the atmosphere associated with greenhouse warming.

Model simulations of 20th century global warming typically use actual observed amounts of atmospheric carbon dioxide, together with other human (for example chloroflorocarbons or CFCs) and natural (solar brightness variations, volcanic eruptions,...) climate - forcing factors.

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.

Studies such as Otto et al. (2012) display how the numerical scale of the simulation numbers allows for clear separation between a climate with lower level of heat - trapping gases (1960s) and the recent period (2000s), such that the 2010 heat wave in western Russia was more likely to occur with the additional warming due to climate change (Figure 3).

To investigate cloud — climate feedbacks in iRAM, the authors ran several global warming scenarios with boundary conditions appropriate for late twenty - first - century conditions (specifically, warming signals based on IPCC AR4 SRES A1B simulations).

The ocean warming rates are much larger in the 20th century simulations, with an average four times larger than the control in the late 20th century simulations.

This analysis by Sedláček & Knutti (2012) does not attempt to connect modelled and observed ocean warming patterns with human activity, but does demonstrate that natural variability is incompatible with the warming in the 20th century simulations, and with historical observations.

Running simulations with an Earth System model, the researchers find that if atmospheric CO2 were still at pre-industrial levels, our current warm «interglacial» period would tip over into a new ice age in around 50,000 years» time.

Methods: In these experiments, the research team conducted large ensembles of simulations with two state - of - the - art atmospheric general circulation models by abruptly switching the sea - surface temperature warming on from January 1st to focus on the wintertime circulation adjustment.

Scientists at Lawrence Livermore National Laboratory within the Atmospheric, Earth, and Energy Division, along with collaborators from the U.K. Met Office and other modeling centers around the world, organized an international multi-model intercomparison project, name CAUSES (Clouds Above the United States and Errors at the Surface), to identify possible causes for the large warm surface air temperature bias seen in many weather forecast and climate model simulations.

First, most climate simulations, including ours above and those of IPCC [1], do not include slow feedbacks such as reduction of ice sheet size with global warming or release of greenhouse gases from thawing tundra.

Because this issue continues to affect all coupled ocean - atmosphere models (e.g., 22 — 24), the warming (Fig. 3) represents the expression of positive biotic feedback mechanisms missing from earlier simulations of these climates obtained with prescribed PI concentrations of trace GHGs.

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.

The model simulation quite clearly indicates that any natural «AMO» surface warming of the tropical Atlantic should be in phase with a strengthening, not a weakening, of the THC.

WebHubTelescope — That's part of the picture but it is commonly stressed, with good reason, that land - sea warming contrast is a feature of equilibrium simulations as well as transient.

It discusses the only the impact of the ocean on rates of warming and how that reduced expected trends in Antarctica with respect to earlier simulations that did not include such effects.

Looking over long term simulations in some of the AR4 models, I've often gotten the impression of a decadal warming / plateau alternation (and in some the Dust Bowl warm years even line up with a warm phase).

Computer simulations of the atmosphere and ocean, when run with rising greenhouse gases, show the warm pool heating at the same rate as other ocean regions, in contrast to what has been observed there so far, the researchers said.

It is not that the polar regions are amplifying the warming «going on» at lower latitudes, it is that any warming going on AT THE POLES is amplified through inherent positive feedback processes AT THE POLES, and specifically this is primarily the ice - albedo positive feedback process whereby more open water leads to more warming leads to more open water, etc. *** «Climate model simulations have shown that ice albedo feedbacks associated with variations in snow and sea - ice coverage are a key factor in positive feedback mechanisms which amplify climate change at high northern latitudes...»

Using the business - as - usual scenario for GHG radiative forcing (RCP8.5) and their novel estimate of Earth's warm - phase climate sensitivity the authors find that the resulting warming during the 21st century overlaps with the upper range of the Coupled Model Intercomparison Project Phase 5 (CMIP5) climate simulations.

Dr. Judith Curry notes «The most recent climate model simulations used in the AR5 indicate that the warming stagnation since 1998 is no longer consistent with model projections even at the 2 % confidence level» This means the hypothesis upon which these models have been built is wrong and should be abandoned.

For instance, perfect initialization of the state of the Atlantic ocean, a correct simulation of the next 10 years of the solar cycle, a proper inclusion of stratospheric water vapor, etc may be important for whether the next 5 years are warmer than the previous 5, but it has nothing to do with climate sensitivity, water vapor feedback, or other issues.

«The consensus had been that global warming was delaying the monsoon... which is also what we found with the simulation if you didn't correct the SST biases,» Pascale said.

These observations, together with computer model simulations and historical climate reconstructions from ice cores, ocean sediments and tree rings all provide strong evidence that the majority of the warming over the past century is a result of human activities.

Moreover, it also includes a number of detection and attribution studies, the IPCC's «gold standard» in terms of inferring climate change and establishing consistency of AO - GCM simulations of greenhouse gas induced warming with observations.

As shown in Figure 2, the IPCC FAR ran simulations using models with climate sensitivities (the total amount of global surface warming in response to a doubling of atmospheric CO2, including amplifying and dampening feedbacks) correspoding to 1.5 °C (low), 2.5 °C (best), and 4.5 °C (high).

Even in the warmest scenario, fewer than 5 % of model simulations of the long - term, 80 - year trend agree with observations by 2020 and fewer than 2.5 % agree by 2030.

Climate scenarios from the Half a degree Additional warming, Projections, Prognosis and Impacts project (HAPPI) are largely consistent with transient scenarios extracted from RCP4.5 simulations of the Coupled Model Intercomparison Project phase 5 (CMIP5).

«The simulations rule out (at the 95 % level) zero trends for intervals of 15 years or more, suggesting that an absence of warming of this duration is needed to create a discrepancy with the observed warming rate.»

2.10 All model simulations, whether they were forced with increased concentrations of greenhouse gases and aerosols or with increased concentrations of greenhouse gases alone, show the follow - ing features: greater surface warming of the land than of the sea in winter; a maximum surface warming in high northern latitudes in winter... All these changes are associated with identifiable physical mechanisms.

Option C won't make it go away either because simulations are so massaged by confirmation bias that many reasonable people, understanding this, may tentitively choose option A. On the other hand, the problem of catastrophic global warming may well go away with additional data.

The AMO during the Little Ice Age was characterized by a quasi-periodicity of about 20 years, while the during the Medieval Warm Period the AMO oscillated with a period of about 45 to 65 years... The observed intermittency of these modes over the last 4000 years supports the view that these are internal ocean - atmosphere modes, with little or no external forcing... However, the geographic variability of these periodicities indicated by ice core data is not captured in model simulations.»

Whereas most proxy - based reconstructions point to an early - middle LIG climatic optimum with reduced summer sea ice concentrations between 126 and 116 ka, the results of our model simulations only support a pronounced reduction in summer sea ice concentration for the LIG - 125 and LIG - 130 runs (in both time slice as well as transient runs; Figs. 8 and 9), but also indicate that sea ice was still present in the central Arctic Ocean even under climatic conditions significantly warmer than today (Fig. 4).

Consequently, for large hard emissions floors, atmospheric levels of CO2 continue to rise throughout our 750 - year simulation, and are still increasing at the end of the experiment, along with associated levels of mean global warming.

This pattern can not be explained by natural variability alone, and is consistent with model simulations of a warming climate.2

And from NOAA:» The simulations rule out (at the 95 % level) zero trends for intervals of 15 yr or more, suggesting that an observed absence of warming of this duration is needed to create a discrepancy with the expected present - day warming rate.»

Coupled simulations, using six different models to determine the ocean biological response to climate warming between the beginning of the industrial revolution and 2050 (Sarmiento et al., 2004), showed global increases in primary production of 0.7 to 8.1 %, but with large regional differences, which are described in Chapter 4.

Although there is less warming at low latitudes than at high northern latitudes, there is also less internal variability at low latitudes, which results in a greater separation of the climate simulations with and without anthropogenic forcings.

TCADI simulations show enhanced warming due to greater sensitivity to CO2, aerosol effects, and greater methane feedbacks, and recovery is much slower in RCP2.6 than with the NINT and TCAD versions.

Given past non-stationarity, and particularly erratic LIA, a «warm LIA» climate scenario for the coming century that combines high precipitation variability (similar to LIA conditions) with warm and dry conditions (similar to MCA conditions) represents a plausible situation that is supported by recent climate simulations.

«Because of the pronounced effect of interannual noise on decadal trends, a multi-model ensemble of anthropogenically - forced simulations displays many 10 - year periods with little warming.

Wynant et al. showed a similar negative overall feedback with warming over all latitudes, based on model simulations using superparameterization to better simulate cloud behavior.

-- Wyant et al. (2007) show net negative cloud feedback with warming using model simulations with superparameterization for clouds.

Climate simulations are consistent in showing that the global mean warming observed since 1970 can only be reproduced when models are forced with combinations of external forcings that include anthropogenic forcings (Figure 9.5).

The only evidence the government scientists provide on the key points of attribution (the cause of the warming) come from simulations of the climate done with computers.

Furthermore, a paper just published by the Journal of Climate concludes that high estimates of future global warming from most computer climate simulations are inconsistent with observed warming since 1850.

Based on Monte Carlo simulations and considering experimental designs with a fixed budget for the number of simulations that modeling centers can perform, the most accurate estimate of historical greenhouse gas — induced warming is obtained with a design using a combination of all - forcings, natural forcings — only, and aerosol forcing — only simulations.