Sentences with phrase «atmospheric water vapor feedbacks»

Not exact matches

In an essay in BioScience magazine, the Wildlife Conservation Society's Douglas Sheil and co-authors discuss the «biotic pump» hypothesis of Russian researchers Anatassia Makarieva and Victor Gorshov, which contends that rainforests attract water vapor, leading to rain, lower local atmospheric pressure and a feedback loop that keeps the whole system going.

Even models that correctly capture cloud behavior may fail to fully account for other climate feedbacks from factors like changing snow and sea ice cover, atmospheric water vapor content, and temperature.

The factors that determine this asymmetry are various, involving ice albedo feedbacks, cloud feedbacks and other atmospheric processes, e.g., water vapor content increases approximately exponentially with temperature (Clausius - Clapeyron equation) so that the water vapor feedback gets stronger the warmer it is.

The important point here is that a small external forcing (orbital for ice - ages, or GHG plus aerosols & land use changes in the modern context) can be strongly amplified by the positive feedback mechanism (the strongest and quickest is atmospheric water vapor - a strong GHG, and has already been observed to increase.

This provides a stable reference temperature structure for the fast feedback processes to operate and maintain the amounts of atmospheric water vapor and clouds at their quasi-equilibrium concentrations.

A particularly serious omission of the Carlin «report» is the latest research on the atmospheric H2O response to greenhouse - driven warming [«Water - vapor climate feedback inferred from climate fluctuations,» in GEOPHYSICAL RESEARCH LETTERS, VOL.

Thus, the phase change of water from liquid to gas, after absorbing photons, is a feedback, the absorption of photons and the emission of photons atmospheric water vapor is a forcing, but the photons released when gaseous water become liquid water is a feedback.

Add CO2 — > increased atmospheric LW absorption — > direct radiative constraint from the E (SRF, clear) = 2OLR (clear) geometric requirement — > immediate (instantaneous) negative radiative water vapor feedback.

The typical logic is this: adding CO2 — > increased atmospheric LW absorption — > temperature adjustment — > negative water vapor / cloud feedback.

Of course, when it comes to the atmospheric temperature increase caused by a doubling of CO2, the water vapor feedback is critical in determining the final outcome.

At this point since there are papers out there that suggest a negative feedback and the 2.5 + x positive water vapor feedback from the IPCC is clearly a non-starter in view of the pause, CAGW has to demonstrate via real atmospheric studies what the actual feedback is.

Results of previously published empirical studies are used to demonstrate that the water vapor feedback mechanism, so important to the calculation of a significant climatic effect for a doubling of the atmospheric CO2 concentration, appears to be counter-balanced by another feedback mechanism of opposite sign.

Pinatubo was particularly good for this, because as Soden et al 2002 showed, the GCMs of the day not only accurately modeled the atmospheric drying after the eruption, but also demonstrated that a positive water vapor feedback was required to explain the MSU - measured lower troposphere temperatures.

The results, summarized in Fig. 2, show unequivocally that the radiative forcing by noncondensing GHGs is essential to sustain the atmospheric temperatures that are needed for significant levels of water vapor and cloud feedback.

The physics is very clear that CO2 is the principal greenhouse forcing gas, and that atmospheric water vapor acts as a feedback magnifier that enhances the terrestrial greenhouse effect.

Part Four — discussion and results of a paper by Dessler et al using the latest AIRS and CERES data to calculate current atmospheric and water vapor feedback vs height and surface temperature

Andrew Lacis wrote: (3) Water vapor and clouds account for about 75 % the strength of the terrestrial greenhouse effect, but are feedback effects that require sustained radiative forcing to maintain their atmospheric distribution.

Non-condensing greenhouse gases, which account for 25 % of the total terrestrial greenhouse effect, thus serve to provide the stable temperature structure that sustains the current levels of atmospheric water vapor and clouds via feedback processes that account for the remaining 75 % of the greenhouse effect.

A. Lacis writes «The physics is very clear that CO2 is the principal greenhouse forcing gas, and that atmospheric water vapor acts as a feedback magnifier that enhances the terrestrial greenhouse effect.

1 Positive 1.1 Carbon cycle feedbacks 1.1.1 Arctic methane release 1.1.1.1 Methane release from melting permafrost peat bogs 1.1.1.2 Methane release from hydrates 1.1.2 Abrupt increases in atmospheric methane 1.1.3 Decomposition 1.1.4 Peat decomposition 1.1.5 Rainforest drying 1.1.6 Forest fires 1.1.7 Desertification 1.1.8 CO2 in the oceans 1.1.9 Modelling results 1.1.9.1 Implications for climate policy 1.2 Cloud feedback 1.3 Gas release 1.4 Ice - albedo feedback 1.5 Water vapor feedback 2 Negative 2.1 Carbon cycle 2.1.1 Le Chatelier's principle 2.1.2 Chemical weathering 2.1.3 Net Primary Productivity 2.2 Lapse rate 2.3 Blackbody radiation

Re: «atmospheric water vapor acts as feedback magnifier» How do you quantify and validate the global magnitude of impacts (INCLUDING CLOUDS) or even whether they are positive or negative?

Noncondensing greenhouse gases, which account for 25 % of the total terrestrial greenhouse effect, thus serve to provide the stable temperaturestructure that sustains the current levels of atmospheric water vapor and clouds via feedback processes that account for the remaining 75 % of the greenhouse effect.

Noncondensing greenhouse gases, which account for 25 % of the total terrestrial greenhouse effect, thus serve to provide the stable temperature structure that sustains the current levels of atmospheric water vapor and clouds via feedback processes that account for the remaining 75 % of the greenhouse effect.

(3) Water vapor and clouds account for about 75 % the strength of the terrestrial greenhouse effect, but are feedback effects that require sustained radiative forcing to maintain their atmospheric distribution.

The future monitoring of atmospheric processes involving water vapor will be critical to fully understand the feedbacks in the climate system leading to global climate change.

It's my understanding that NVAP data shows as atmospheric CO2 increases, water vapor decreases; exactly opposite what climate models predict because they assume water vapor is a net positive feedback; more wv, more warming, more wv, more warming.....

The Equilibrium Climate Sensitivity (ECS) The Economist refers to is how much Earth temperatures are expected to rise when one includes fast feedbacks such as atmospheric water vapor increase and the initial greenhouse gas forcing provided by CO2.

The IPCC, its models, and the climate establishment insist warming will be more than this because the warming will cause an increase in atmospheric water vapor (the major greenhouse gas) which will amplify the CO2 - caused warming, a net positive feedback.

States that other feedbacks likely to emerge are those in which key processes include surface fluxes of trace gases, changes in the distribution of vegetation, changes in surface soil moisture, changes in atmospheric water vapor arising from higher temperatures and greater areas of open ocean, impacts of Arctic freshwater fluxes on the meridional overturning circulation of the ocean, and changes in Arctic clouds resulting from changes in water vapor content

Fast feedbacks are changes of quantities such as atmospheric water vapor and clouds, which change as climate changes, thus amplifying or diminishing climate change.

Early work at GFDL relating to carbon focused on CO2 as a greenhouse gas and it's potential for doubling in response to human activities, through water vapor and other atmospheric feedbacks in the context of latitudinal, land - sea and other inhomogeneities influencing climate (e.g. Manabe 1968, 1986, 1987).

Principal positive feedback processes in the model are changes in atmospheric water vapor, clouds and snowlice cover.

Negative trends in q as found in the NCEP data would imply that long - term water vapor feedback is negative — that it would reduce rather than amplify the response of the climate system to external forcing such as that from increasing atmospheric CO2.

The basic results of this climate model analysis are that: (1) it is increase in atmospheric CO2 (and the other minor non-condensing greenhouse gases) that control the greenhouse warming of the climate system; (2) water vapor and clouds are feedback effects that magnify the strength of the greenhouse effect due to the non-condensing greenhouse gases by about a factor of three; (3) the large heat capacity of the ocean and the rate of heat transport into the ocean sets the time scale for the climate system to approach energy balance equilibrium.

Once permafrost starts melting, there are feedbacks from changes in albedo, methane emissions, the thermal properties of surface water, and increases in atmospheric water vapor.

Regardless, climate models are made interesting by the inclusion of «positive feedbacks» (multiplier effects) so that a small temperature increment expected from increasing atmospheric carbon dioxide invokes large increases in water vapor, which seem to produce exponential rather than logarithmic temperature response in the models.

The direct CO2 radiative forcing is the change in infrared radiative fluxes for a doubling CO2 (typically from 287 to 574 ppm), without any feedback processes (e.g. from changing atmospheric water vapor amount or cloud characteristics.)

Is there some sort of a «natural thermostat» mechanism by which atmospheric water vapor content is regulated to prevent a long - term «positive feedback» from water vapor, as is assumed by all the IPCC climate models?

The question that this raises: Is there some sort of a «natural thermostat» mechanism by which atmospheric water vapor content is regulated to prevent a long - term «positive feedback» from water vapor, as is assumed by all the IPCC climate models?