Sentences with phrase «assumed constant relative humidity»

Actual physical observations have shown that net cloud feedback is very likely to be negative rather than strongly positive and that the net water vapor plus lapse rate feedback is around half of the amount estimated with assumed constant relative humidity.

Presumably the water vapour feedback in models is dealt with by determining / estimating / calculating the radiative forcing from water vapour and then making some assumption about the water vapour response to atmospheric warming (e.g. assuming constant relative humidity).

They had built the first completely correct radiative - convective implementation of the standard model applied to Earth, and used it to calculate a +2 C equilibrium warming for doubling CO2, including the water vapour feedback, assuming constant relative humidity.

Not exact matches

The modes assume near constant leves of water vapor, but they are not necessarily so close, however, water tends towards equilibrium, so in the long run, the mode averages may not be far off in that regard, but relative humidity does vary greaty, especially during shorter periods of time.

And, since IPCC assumed essentially constant relative humidity with warming to arrive at the water vapor feedback and it appears that RH decreases with warming (Minschwaner + Dessler 2005, NOAA radiosonde and satellite humidity records), the water vapor feedback is very likely too high by around 0.3 C to 0.6 C, bringing the overall adjusted ECS to roughly 0.9 C to 1.2 C.

IOW we have both the magnitude and the sign of water vapor feedback still in question (except, of course, by the IPCC orthodoxy, which assumes positive feedback at a rate high enough to essentially maintain constant relative humidity in lockstep with Clausius - Clapeyron).

One such feedback might exist if, as assumed in some models, relative humidity is constant, so increasing the temperature has the positive feedback of increasing the water vapor.

Therefore, assuming that the relative humidity remains about constant, the strength of the greenhouse effect will increase with surface temperature.

I believe the declining one is relative humidity, declining as CO2 and temperature go up (instead of remaining constant, as GCMs assume).

(We have good reasons to assume relative humidity will remain constant in the boundary layer and in air which has recently been in contact with the boundary layer.)

But, I think it's quite reasonable to demand good evidence for these purported feedbacks and in the absence of that evidence assume the simple physics of radiation and humidity dependence at constant relative humidity hold.