Sentences with phrase «when atmospheric models»

* * * The evidence to support the theory of anthropogenic, or human - caused, climate change has been mounting since the mid-1950s, when atmospheric models predicted that growing levels of CO2 in the atmosphere would add to the natural «greenhouse effect» and lead to warming.

I understand that global surface temperatures are not responding as rapidly as they should be when the atmospheric models are considered.

I understand that global surface temperatures are not responding as rapidly as they should be when the atmospheric models are considered.

Not exact matches

The US model performed on average as well as, or better than, the European model when using the full suite of atmospheric data from the ECMWF.

When Douglas MacMartin of the California Institute of Technology in Pasadena approached the National Science Foundation for support on a modeling effort on [albedo modification], officials told him the work was too theoretical for the engineering division and too applied for the atmospheric science program.

«Exactly when is model - dependent, but what is clear is that the formation of continental crust naturally leads to two rises in atmospheric oxygen, just as we see in the fossil record,» Lee said.

Scientists finally confirmed this hypothesis in the 1960s when it became possible to develop adequate models of solar atmospheric heating.

Both models help mission team members plan when and where to look for unusual atmospheric disturbances as Titan summer approaches.

The atmospheric components of climate models were never really designed for the study of TCs, but the fact that they can produce features with TC - like character when run at sufficiently high resolutions, gives us increased confidence in the possibility that climate models can be used to analyze climate change impacts on TCs.

The lag between decreases in sea ice extent during late summer and changes in the mid-latitude atmospheric circulation during other seasons (like autumn and winter, when the recent loss of sea ice is much smaller) have been demonstrated empirically, but have not been captured by existing dynamical models.

The combination of observation - based estimates... with NCAR CSM1.4 - carbon model projection indicates that 10 % of the surface water along the investigated Arctic transect will become undersaturated for at least one month of the year when atmospheric CO2 exceeds 409 ppm.

When GCMs are used to model atmospheric conditions and spatial grid size is reduced is there a scale at which chaotic conditions prevail and make modeling difficult in the same way that weather is harder to model than climate?

When the reseachers at the Center for International Climate and Environmental Research — Oslo (CICERO) applied their computer «model and statistics to analyse temperature readings from the air and ocean for the period ending in 2000, they found that climate sensitivity to a doubling of atmospheric CO2 concentration will most likely be 3.7 °C, which is somewhat higher than the IPCC prognosis.»

This thesis presents the results of several general circulation model simulations aimed at studying the effect of ocean circulation changes when they occur in conjunction with increased atmospheric trace gas concentrations.

When ocean models were first coupled to atmospheric models well over a quarter century ago, systematic errors in each component near their interface led to sizeable drift and unrealistic climate simulations.

This mode of intra-annual tropical atmospheric variability is strongly associated with California rainfall events when its active phase shifts eastward, as is currently being suggested by dynamical model forecasts.

To illustrate the implications, Weitzman notes that, when we run the climate models, a normal («thin - tailed») distribution of impacts from a doubling of atmospheric greenhouse gas concentrations above pre-industrial levels produces a median temperature change of 3 degrees Celsius with a 15 % probability of a warming above 4.5 degrees Celsius.

Climate sensitivity is not any threat The climate sensitivity (i.e. increase of glogal climate temperature, when atmospheric CO2 content has been doubled) assessed by IPCC — on the basis of climate models results — is uncertain and exaggerated.

I had already been introduced to atmospheric physics whilst on an Erasmus year in Spain, and I knew I liked modelling after having modelled galactic hydrogen lines in my final year physics project (we had to model them, as the radio telescope was kaput - even when pointed at the sun we got no signal).

[18] When models of different physical processes are combined, such as combinations of atmospheric, ocean and wave models, the multi-model ensemble is called hyper - ensemble.

The identified atmospheric feedbacks including changes in planetary albedo, in water vapour distribution and in meridional latent heat transport are all poorly represented in zonal energy balance model as the one used in [7] whereas they appear to be of primary importance when focusing on ancient greenhouse climates.

Using a crop model they compared how well spring wheat in China and groundnuts in West Africa would grow under these scenarios when compared to a third «control» scenario that holds atmospheric carbon dioxide at 440ppm.

Figure 1 shows the increase in model atmospheric dust when this source is added, relative to a simulation without the added dust source.

For new technologies the ETA team often starts with a life - cycle energy, water, or materials analysis to understand the technology's impacts when scaled up, and then uses other models as needed, such as an atmospheric chemistry model or energy system model.

In particular the satellites show zero overall atmospheric warming during the 1978 - 1997 period, which is when the surface statistical models show the supposed warming that AGW is based on.

Answer: if warming releases CO2 from the ocean, whether coming out of an ice age or when initiated by ACO2, it upsets IPCC's model that the bulge in atmospheric CO2 measured at MLO is all due to man.

But almost universally, when they try to explain it, they all use the purely radiative approach, which is incorrect, misleading, contrary to observation, and results in a variety of inconsistencies when people try to plug real atmospheric physics into a bad model

the purely radiative approach, which is incorrect, misleading, contrary to observation, and results in a variety of inconsistencies when people try to plug real atmospheric physics into a bad model

As we now that there has been a period of 18 years with no surface warming when atmospheric CO2 was increasing for each and every year we know that the majority of the warming in the last 50 years was not due to the increase in atmospheric CO2 and the IPCC general circulation model calculated warming due to CO2 is orders of magnitude too high.

The partial radiative perturbations (PRPs) due to changes in cloud and due to the effects of the pre-existing climatological cloud distribution on non-cloud changes, known as «cloud masking», are calculated when atmospheric CO2 concentration is doubled for the HadSM3 and MIROC models and for a large ensemble of parameter perturbed models based on HadSM3.

Trenberth used the Version 5 RSS - SSM / I data set for atmospheric water content, q, to claim that it represented a better choice for observing trends in q when validating climate models.

The IPCC defines Equilibrium climate sensitivity as the change in global mean temperature that results when the climate system, or a climate model, attains a new equilibrium with the forcing change resulting from a doubling of the atmospheric CO2 concentration.

When heavy rainfall probabilities were next investigated in ensembles of two atmospheric general circulation models, run with and without anthropogenically - induced sea surface temperature changes, results were model - dependent.

In other words, we obtained a site specific, tortuosity - depth relationship by adjusting diffusivity until the model reproduced the observed CO2 firn - air profile when driven by the independently derived atmospheric CO2 history (see Fig.

As there are multiple periods in the geological record of tens of millions years in duration when CO2 levels were high and the planet was cold and when CO2 levels were low and the planet was warm, it appears there is a basic fundamental assumption in the model of atmospheric radiation that is incorrect or there is an omission of another mechanism from the standard models of atmosphere radiation.

This model, when forced with observed sea surface temperatures and atmospheric conditions, can reproduce the observed rise in hurricane counts between 1980 and 2012, along with much of the interannual variability (Figure 5).

«The paper by Skinner provides important evidence the Southern Ocean is at least a substantial source of the CO2 increase (by showing a 50 % decrease of 14C in the atmospheric CO2), which is a critical piece of the puzzle when trying to understand, model, and quantify the CO2 source / sink behaviour of the Southern Ocean in a warming world today and in the future.

There are numerous models that show a relationship, but the models omit more elements of atmospheric complexity than they include (and exclude any solar forcing with the exception of irradiance in some models), they can not backcast past ca 1900, they can not forecast next month, and they do generate greatly dissimilar forecasts when fed with the same assumptions of future conditions.

None of these could have been caused by an increase in atmospheric CO2, Model projections of warming during recent decades have greatly exceeded what has been observed, The modelling community has openly acknowledged that the ability of existing models to simulate past climates is due to numerous arbitrary tuning adjustments, Observations show no statistically valid trends in flooding or drought, and no meaningful acceleration whatsoever of pre-existing long term sea level rise (about 6 inches per century) worldwide, Current carbon dioxide levels, around 400 parts per million are still very small compared to the averages over geological history, when thousands of parts per million prevailed, and when life flourished on land and in the oceans.

Since we can not measure any individual forcing directly in the atmosphere, the models draw upon results of laboratory experiments in passing sunlight through chambers in which atmospheric constituents are artificially varied; such experiments are, however, of limited value when translated into the real atmosphere, where radiative transfers and non-radiative transports (convection and evaporation up, advection along, subsidence and precipitation down), as well as altitudinal and latitudinal asymmetries, greatly complicate the picture.