Sentences with phrase «increased stratospheric water vapor»

Lower stratospheric cooling is mainly caused by the effects of ozone depletion with a possible contribution from increased stratospheric water vapor and greenhouse gases increase.

Climate and ozone response to increased stratospheric water vapor.

Shindell, D.T., 2001: Climate and ozone response to increased stratospheric water vapor.

On the other hand, decreasing stratospheric ozone (above 25 km), increasing stratospheric water vapor, and increasing atmospheric CO2 uniformly with height) will produce global surface and tropospheric warming along with stratospheric cooling.

«Stratospheric water vapor has a positive climate feedback effect: a warming climate increases stratospheric water vapor, and the increased stratospheric water vapor enhances surface warming.

Not exact matches

The stratopsheric cooling may be caused by the tropospheric water vapor (see figure 3 of http://www.springerlink.com/content/6677gr5lx8421105/fulltext.pdf)-- but in that figure water vapor is fixed only above sigma = 0.14 (~ 140 hPa), so the cooling may also be caused by the increase in lower stratospheric water vapor.

The most important non-CO2 forcing is methane, whose increases in turn cause tropospheric ozone and stratospheric water vapor to increase.

The relative contribution of each trace GHG to increased Eocene and Cretaceous land temperatures at 4 × CO2, assessed with multiple separate coupled - ocean atmosphere HadCM3L model simulations, revealed methane and associated increases in stratospheric water vapor dominate, with nitrous oxide and tropospheric ozone contributing approximately equally to the remainder.

Oinas et al also show that stratospheric dynamics make their contribution in the polar vortex regions to produce local warming in the 1 mb region for the uniformly applied increase in stratospheric water vapor.

(PS regarding Venus — as I have understood it, a runaway water vapor feedback would have occured when solar heating increasing to become greater than a limiting OLR value (Simpson - Kombayashi - Ingersoll limit — see http://chriscolose.wordpress.com/2010/08/23/climate-feedbacks-part-1/ — although I should add that at more «moderate» temperatures (warmer than today), stratospheric H2O increases to a point where H escape to space becomes a significant H2O sink — if that stage worked fast enough relative to solar brightening, a runaway H2O case could be prevented, and it would be a dry (er) heat.

But then there's feedbacks within the stratosphere (water vapor), which would increase the stratospheric heating by upward radiation from below, as well as add some feedback to the downward flux at TRPP that the upward flux at TRPP would have to respond to via warming below TRPP.

As to the idea of CH4 contributing to an increase in O2 in the atmosphere we are leaving out the recent examples of increased water vapor in the Stratospheric region.

Warming must occur below the tropopause to increase the net LW flux out of the tropopause to balance the tropopause - level forcing; there is some feedback at that point as the stratosphere is «forced» by the fraction of that increase which it absorbs, and a fraction of that is transfered back to the tropopause level — for an optically thick stratosphere that could be significant, but I think it may be minor for the Earth as it is (while CO2 optical thickness of the stratosphere alone is large near the center of the band, most of the wavelengths in which the stratosphere is not transparent have a more moderate optical thickness on the order of 1 (mainly from stratospheric water vapor; stratospheric ozone makes a contribution over a narrow wavelength band, reaching somewhat larger optical thickness than stratospheric water vapor)(in the limit of an optically thin stratosphere at most wavelengths where the stratosphere is not transparent, changes in the net flux out of the stratosphere caused by stratospheric warming or cooling will tend to be evenly split between upward at TOA and downward at the tropopause; with greater optically thickness over a larger fraction of optically - significant wavelengths, the distribution of warming or cooling within the stratosphere will affect how such a change is distributed, and it would even be possible for stratospheric adjustment to have opposite effects on the downward flux at the tropopause and the upward flux at TOA).

«Climate models show cooler stratospheric temperatures happen when there is more water vapor present» «The stratosphere is the typically dry layer of the atmosphere above the troposphere, where temperatures increase with height.»

Instead, they discuss new ways of playing around with the aerosol judge factor needed to explain why 20th - century warming is about half of the warming expected for increased in GHGs; and then expand their list of fudge factors to include smaller volcanos, stratospheric water vapor (published with no estimate of uncertainty for the predicted change in Ts), transfer of heat to the deeper ocean (where changes in heat content are hard to accurately measure), etc..

b) The models all assume that stratospheric water vapor would increase with increasing CO2 (the famous «positive feedback»), but it has actually decreased, providing negative feedback instead.

Some of the mid-latitude increase of stratospheric water vapor (1 % per year) over the period of 1980 - 2006 can be explained by the increase of atmospheric methane, but not all.

The most important non-CO2 forcing is methane, whose increases in turn cause tropospheric ozone and stratospheric water vapor to increase.

«stratospheric water vapor probably increased between 1980 and 2000, which would have enhanced the decadal rate of surface warming during the 1990s by about 30 % as compared to estimates neglecting this change.

Chemistry - climate models predict increases of stratospheric water vapor, but confidence in these predictions is low.

In fact, since 1980 (the start of the data analyzed), an overall increase in stratospheric water vapor content as been responsible for perhaps 15 % of the overall temperature increase.

Soloman and her co-authors argue that El Niño has been one of the drivers of changes in stratospheric water vapor, noting that «The drop in stratospheric water vapor observed after 2001 has been correlated to sea surface temperature (SST) increases in the vicinity of the tropical «warm pool» which are related to the El Niño Southern Oscillation (ENSO).»

They also point out that an increase in stratospheric water vapor during the 1990s may have led to about 30 percent more warming during that decade than otherwise would have occurred.

Recently, there have been debates about the slowing of the warming rates since 2005, with explanations (44 ⇓ — 46) ranging from increases in stratospheric water vapor and background aerosol to increased coal burning in the emergent economy of China of the past 20 y.

The climate model reproduces the temperature trends only when stratospheric water vapor also increases.

Ozone changes in 2055, when the projected equivalent chlorine loading returns to its 1980 value, show the positive impact of stratospheric cooling by GHGs and the negative impact of water vapor increases, which outweigh the cooling.

A few years later, methane levels were indeed found to be rising, and the increase in stratospheric water vapor was confirmed in 1995.