Sentences with phrase «as increasing water vapour»

Simulations with GCMs by Stevenson et al. (2000) and Grewe et al. (2001) for the 21st century indicate a decrease in the lifetime of tropospheric ozone as increasing water vapour enhances the dominant ozone sink from the oxygen radical in the 1D excited state (O (1D)-RRB- plus water (H2O) reaction.

Not exact matches

This is a function of the increase in fractionation as water vapour is continually removed from the air.

And that additional water vapour would in turn cause further warming - this being a positive feedback, in which carbon dioxide acts as a direct regulator of temperature, and is then joined in that role by more water vapour as temperatures increase.

Source: Lyman 2010 The reaction of the oceans to climate change are some of the most profound across the entire environment, including disruption of the ocean food chain through chemical changes caused by CO2, the ability of the sea to absorb CO2 being limited by temperature increases, (and the potential to expel sequestered CO2 back into the atmosphere as the water gets hotter), sea - level rise due to thermal expansion, and the amount of water vapour in the atmosphere.

Scientists agree that a doubling of atmospheric CO2 levels could result in temperature increases of between 1.5 and 4.5 °C, caused by rapid changes such as snow and ice melt, and the behaviour of clouds and water vapour.

The increase in water vapour as the surface warms is key, but so might be changes in boundary layer stability, rossby wave generation via longitudinally varying responses at the surface, impacts of the stratopshere on the steering of the jet, and the situation is completely different again for tropical storms.

Indeed, there is a clear physical reason why this is the case — the increase in water vapour as surface air temperature rises causes a change in the moist - adiabatic lapse rate (the decrease of temperature with height) such that the surface to mid-tropospheric gradient decreases with increasing temperature (i.e. it warms faster aloft).

As I understand all models they all predict a water vapour based forcing caused by increased temperatures leading to increased levels of water vapour and hence an increased greenhouse effect.

Other feedbacks include forests, and most importantly, water vapour, which as the temperature of the atmosphere rises increases in the atmosphere (think tropical rain forest), and water vapour is a potent greenhouse gas (but it is not the «controller» of our climate because it does not accumulate in the atmosphere, only gases like CO2, methane and nitrous oxide do this) See Skeptical Science https://skepticalscience.com/co2-lags-temperature.htm

The rise of CO2 from 270ppm to now over 400ppm, the extent of equatorial and sub tropical deforestation, the soot deposits on the polar ice caps, the increase in atmospheric water vapour due to a corresponding increase in ocean temps and changes in ocean currents, the extreme ice albedo currently happening in the arctic etc, etc are all conspiring in tandem to alter the climate as we know it.

Furthermore natural global temperature swings alter the natural background greenhouse effect constantly as water vapour held in the atmosphere increases and decreases naturally with changing global temperatures.

The IPCC's AR5 indicates that, apart from the Water Vapour Increase feedback, permafrost melt and the other main feedbacks were viewed as being insignificant to the outcome of the RCP scenarios.

The atmosphere now holds 4 % more water vapour than it did 40 years ago as a result of increasing temperatures.

While what I have described is a bit simplistic, it gives the gist of why the CO2 emissions are significant: not only is CO2 a greenhouse gas, but its effect causes other significant changes to take place, such as increased uptake of water vapour into the atmosphere.

Line - by - line computer code simulations show that a 10 % increase in CO2 concentration has the same effect as a uniform 1.80 % change in water vapour on the out - going longwave radiation.

One idea was that increased IR radiated from water vapour in these air masses could off - set expansion due to release of latent heat, and ad drive horizontal circulation This had to be attacked as it showed a role for radiative gases in atmospheric circulation.

As the planet warms, increasing levels of water vapour in the atmosphere caused by higher evaporation levels form more clouds and snow increasing the albedo of the planet, reflecting heat back into space more efficiently, thus working to regulate the temperature downward.

If water vapour feedback was positive then due to the increased evaporation spurred on by the original warming in the MWP there should have ensued a period of elevated temperatures for thousands of years until the cooling of the Holocene as we dip into the next glacial period overwhelmed the positive water vapour forcing.

Source: Lyman 2010 The reaction of the oceans to climate change are some of the most profound across the entire environment, including disruption of the ocean food chain through chemical changes caused by CO2, the ability of the sea to absorb CO2 being limited by temperature increases, (and the potential to expel sequestered CO2 back into the atmosphere as the water gets hotter), sea - level rise due to thermal expansion, and the amount of water vapour in the atmosphere.

A slight change of ocean temperature (after a delay caused by the high specific heat of water, the annual mixing of thermocline waters with deeper waters in storms) ensures that rising CO2 reduces infrared absorbing H2O vapour while slightly increasing cloud cover (thus Earth's albedo), as evidenced by the fact that the NOAA data from 1948 - 2008 shows a fall in global humidity (not the positive feedback rise presumed by NASA's models!)

Basically, Dr Ferenc Miskolczi's life as a NASA climate research scientist was made hell because he discovered that the extra water vapour being evaporated is not having a positive - feedback (increasing the CO2 warming effect by absorbing more infrared from the sun), instead it is going into increased cloud cover, which reflects incoming sunlight back to space.

This radiative response by the system is due predominantly to increased thermal radiation, but it is modified by climate feedbacks such as changes in water vapour, clouds and surface albedo, which affect both outgoing longwave and reflected shortwave radiation.

The relative humidity suggests as well that the OLR from the water vapour in the spectral regions where figure 6 - A shows high optical thickness has been slowly increasing, as the source of radiation to the cosmos moved to slightly «lower and warmer» layers.

So, that's 1.2 degrees C for the basic physics of added greenhouse effect of a doubling of carbon dioxide in the atmosphere; coupled with a further increase of a similar magnitude from changes in atmospheric water vapour that come about as a direct consequence.

Some point to aerosols (but that is not very plausible, as that should give an increase since 1975 for Europe and in part for North America), but I have the impression that increased water vapour levels are at the base of this change.

That increases the CO2 levels near the sea surface (but that is readlily dispersed by convection, as good as the water vapour).

As climate forcing and temperature increase, the amount of water vapour in the air increases and clouds may change.

As air warms it can hold more water, the increase in water vapour is said to be responsible for a possible amplification of global warming as the temperature warmAs air warms it can hold more water, the increase in water vapour is said to be responsible for a possible amplification of global warming as the temperature warmas the temperature warms.

Hence, even as the potential for heavier precipitation results from increased water vapour amounts, the duration and frequency of events may be curtailed, as it takes longer to recharge the atmosphere with water vapour.

High sensitivity is caused by increasing water vapour as the tropopause rises and diminishing low cloud cover, but the sensitivity decreases for still larger CO2 as cloud optical thickness and planetary albedo increase, as shown by Russell et al. [112].

It is well known that a doubling of atmospheric CO2 levels could result in temperature increases of between 1.5 and 4.5 °C, due to fast changes such as snow and ice melt, and the behaviour of clouds and water vapour.

Oh and, while the water vapour content of air may be dependent on temperature, cloud cover certainly isn't No, not entirely, but increased water vapour is the main contributors to cloud formation, and, as you almost point out, increased temperature increases water vapour in the atmosphere.

Bear in mind that the representation of clouds in climate models (and of the water vapour which is intimately involved with cloud formation) is such as to amplify the forecast global warming from increasing atmospheric carbon dioxide — on average over most of the models — by a factor of about three (5).

Total water vapour in the atmosphere may increase as the temperature of the surface rises, but if at the same time the mid - to upper - level concentration decreases then water vapour feedback will be negative.

Lindzen doesn't really separate them, he talks about low level cloud feedbacks as being one of the major negative feedbacks that would accrue from increased water vapour and is still consistently saying the same thing.

-- GHGs can work both as forcing and as feedback, the notion is clear, also that water vapour is a positive feedback effect — When water warms the amount of water vapour will increase, as will C02

This is based on the increase in CO2 concentration needed to make the gas as effective as water vapour in absorbing LWIR ie based on equivalence:

This is based on the increase in CO2 concentration needed to make the gas as effective as water vapour in absorbing LWIR ie based on equivalence: For a product term PwL of 0.0231 * (4 * 3.281) ft.atm a water vapour absorptivity of o. 2 absorbs 84Wm - 2 of land LWIR in 4m.

R Stevenson says: May 22, 2011 at 9:07 am This is based on the increase in CO2 concentration needed to make the gas as effective as water vapour in absorbing LWIR ie based on equivalence: For a product term PwL of 0.0231 * (4 * 3.281) ft.atm a water vapour absorptivity of o. 2 absorbs 84Wm - 2 of land LWIR in 4m.

But it was cold this winter and C02 is plant food and only a trace gas and the greenhouse effect has been disproved anyway and even if the greenhouse effect does exist, C02 has negligible impact compared to water vapour and our only source of heat is the sun so it must be the sun, unless it is due to the C02 from volcanoes, but C02 follows warming so it can't be the C02 and the medieval warm period was warmer anyway and all the temperature reconstructions that show this not to be true are produced by corrupt scientists being paid by corrupt governments that have colluded to create an excuse to form a one world unelected social - ist government and even if the scientists are not that corrupt, although the e-mails prove they are, they have still got it wrong as the climate sensitivity is not as high as they think it is because it is basically the planets orbits and cosmic rays so we can say for a fact that the warming that probably does not exist is definatley not due to humans and even if it was the evidence is not sufficient to make drastic changes to the economy and increase taxes so that the politicians and scientists and business leaders get rich and leave us all poor — do they think we are stupid or something?

The average atmospheric water vapour content has increased since at least the 1980s over land and ocean as well as in the upper troposphere.

Increases in CO2 have very little effect in this water vapour dominated environment as it is a very weak absorber.

As a result of climate warming, water vapour increases, which is a feedback loop.

As you equilibriate, the planet warms (reducing the TOA imbalance) and water vapour increases, increasing the amount of surface LW absorbed in the atmosphere, but not adding to the TOA imbalance (though it does slow the equilibration).

The link between heat and Hurricane intensity is unquestionable, as atmospheric water vapour density increases with higher temperatures, the energy source is likewise augmented, same goes for cyclones.

Increased water vapour = > clouds = > net cooling effect as we all know.

The models (and there are many) have numerous common behaviours — they all cool following a big volcanic eruption, like that at Mount Pinatubo in 1991; they all warm as levels of greenhouse gases are increased; they show the same relationships connecting water vapour and temperature that we see in observations; and they can quantify how the giant lakes left over from the Ice Age may have caused a rapid cooling across the North Atlantic as they drained and changed ocean circulation patterns.

And that additional water vapour would in turn cause further warming - this being a positive feedback, in which carbon dioxide acts as a direct regulator of temperature, and is then joined in that role by more water vapour as temperatures increase.

Due to «climate cell convection», and the property of being lighter than air, a «water vapour» (WV) molecule finds itself rising to increasing altitudes through the «adiabat» (as altitude increases the temperature of an «adiabatic atmosphere» decreases) of the troposphere.

This would have the effect of generally dampening daytime temps but increasing nighttime temps (increased water vapour and the released CO2 from the warming oceans, acting as an insulator).