Sentences with phrase «warming effect of clouds»

The net effects of clouds on the nighttime minimum temperature is small except in the winter high latitudes where the greenhouse warming effect of clouds exceeds their solar cooling effect.

Not exact matches

Scientists can measure how much energy greenhouse gases now add (roughly three watts per square meter), but what eludes precise definition is how much other factors — the response of clouds to warming, the cooling role of aerosols, the heat and gas absorbed by oceans, human transformation of the landscape, even the natural variability of solar strength — diminish or strengthen that effect.

Besides SSCE, scientists have also been investigating stratospheric sulfur injections — firing sun - reflecting aerosols into the air, similar to the cooling effect after a volcanic eruption — and cirrus cloud thinning, where you thin the top level of clouds, which have a warming effect on the planet.

In a recent study, for instance, well - respected climate models were shown to have completely opposing estimates for the overall effect of the clouds and smoke in the southeast Atlantic: Some found net warming, whereas others found cooling.

These sulphur containing particles reflect sunlight and help form brighter clouds, creating a global effect that temporarily diminishes the warming effects of carbon dioxide.

Scientists have been interested in the effects of pollution on Arctic clouds because of their potential warming effect.

It may seem surprising to people, but you can look at something like Mars, which has a very thin atmosphere, and you can look at something like Venus which we tend to think of as sort of having this rather heavy, clouded atmosphere, which [is] hellishly warm because of runaway greenhouse effect, and on both of those planets you are seeing this phenomenon of the atmosphere leaking away, is actually what directly has led to those very different outcomes for those planets; the specifics of what happened as the atmosphere started to go in each case [made] all the difference.

Scientists know that the clouds can act as a sunshield, cooling parts of the globe and offsetting the global warming caused by the greenhouse effect (see «Not warming, but cooling», New Scientist, 9 July 1994).

The theory of dangerous climate change is based not just on carbon dioxide warming but on positive and negative feedback effects from water vapor and phenomena such as clouds and airborne aerosols from coal burning.

And, Stevens says, the study doesn't discuss the types of clouds that are thought to be the most crucial for future warming: low - lying clouds over the subtropical oceans, which have a strong cooling effect but may be dissipating as the world warms.

The research also appears to solve one of the great unknowns of climate sensitivity, the role of cloud formation and whether this will have a positive or negative effect on global warming.

«There's other things besides just warming — there's cloud cover and rain that can ameliorate the effects of the warming.

[Response: Note also that more low clouds would unambiguously mean a cooling effect, but more high clouds could lead to either a warming effect or a cooling effect, depending on the altitude of the clouds and the typical particle size in the GCR - induced clouds (if any).

They tend to believe that as the planet warms, low - level cloud cover will increase, thus increasing planetary albedo (overall reflectiveness of the Earth), offsetting the increased greenhouse effect and preventing a dangerous level of global warming from occurring.

The net effect of human - generated aerosols is more complicated and regionally variable — for example, in contrast to the local warming effect of the Asian Brown Cloud, global shipping produces large amounts of cooling reflective sulphate aerosols: http://www.sciencedaily.com/releases/1999/08/990820022710.htm

Accounting for pollution effects on storm clouds in this way could affect the ultimate amount of warming predicted for the earth in the next few decades.

Constable would often record his thoughts on the back of the studies, for example on Branch Hill Pond, Hampstead he writes: «We have had noble clouds and effects of light and dark and colour — as is always the case with such seasons as the present», while on Cloud Study, Hampstead he describes a «morning under the sun, clouds silvery grey on warm sultry ground».

Data from satellite observations «suggest that greenhouse models ignore negative feedback produced by clouds and by water vapor, that diminish the warming effects» of human carbon dioxide emissions.

By the way, low clouds in darkness increase surface temperature, sort of like the inverse property of commonly understood Cosmic ray effect, not causing a cooling because there are more CR's, but rather a warming, which only low clouds in total darkness can do, so the probable CR temperature signal gets cancelled from one latitude dark vs bright region to the next.

It is my understanding that the uncertainties regarding climate sensitivity to a nominal 2XCO2 forcing is primarily a function of the uncertainties in (1) future atmospheric aerosol concentrations; both sulfate - type (cooling) and black carbon - type (warming), (2) feedbacks associated with aerosol effects on the properties of clouds (e.g. will cloud droplets become more reflective?)

The relative importance of GHG warming and indirect effect and a revised version of the IPCC TAR of the cloud feedback is exactly what I am working on.

He conveniently ignores that decreased cloud cover could be a result of the warming, executing a cause / effect bait - and - switch on us.

The bottom line is that uncertainties in the physics of aerosol effects (warming from black carbon, cooling from sulphates and nitrates, indirect effects on clouds, indirect effects on snow and ice albedo) and in the historical distributions, are really large (as acknowledged above).

I've touched on lake - effect snows, the classic pattern in the Upper Midwest and western New York State in which frigid winds blowing over relatively warm Great Lakes waters generate persistent cloud bands and lots of snow.

What is the best guess of the experts regarding the balance of the cooling versus warming effects of increasing clouds / water vapor?

Just two remarks: you keep on saying that the effect of increased cloudiness «should be warming», whereas the data shown in the article clearly show the opposite (more clouds cause lower surface level air temperatures).

(Note that radiative forcing is not necessarily proportional to reduction in atmospheric transparency, because relatively opaque layers in the lower warmer troposphere (water vapor, and for the fractional area they occupy, low level clouds) can reduce atmospheric transparency a lot on their own while only reducing the net upward LW flux above them by a small amount; colder, higher - level clouds will have a bigger effect on the net upward LW flux above them (per fraction of areal coverage), though they will have a smaller effect on the net upward LW flux below them.

The second order effect of increasing cloudiness caused by more GCRs when «atmospheric conditions are suitable» for the formation of high clouds due to the other effects of global warming should be warming.

So, the question of whether or not more of these clouds would be formed, along with the question of their net effect (given that they reflect sunlight from above, but also trap heat from below), gives rise to some degree of imprecision when it comes to the degree of warming predicted by models.

Re 9 wili — I know of a paper suggesting, as I recall, that enhanced «backradiation» (downward radiation reaching the surface emitted by the air / clouds) contributed more to Arctic amplification specifically in the cold part of the year (just to be clear, backradiation should generally increase with any warming (aside from greenhouse feedbacks) and more so with a warming due to an increase in the greenhouse effect (including feedbacks like water vapor and, if positive, clouds, though regional changes in water vapor and clouds can go against the global trend); otherwise it was always my understanding that the albedo feedback was key (while sea ice decreases so far have been more a summer phenomenon (when it would be warmer to begin with), the heat capacity of the sea prevents much temperature response, but there is a greater build up of heat from the albedo feedback, and this is released in the cold part of the year when ice forms later or would have formed or would have been thicker; the seasonal effect of reduced winter snow cover decreasing at those latitudes which still recieve sunlight in the winter would not be so delayed).

Higher clouds are an expected effect of warming, and to first order, independent of GCRs — see ftp://eos.atmos.washington.edu/pub/breth/papers/2007/Zhu-etal-LowCldClimSens-JGR-2007.pdf Note the increase in high clouds (Fig2b3) and decrease in low clouds (Fig2e1) downwind of S America in the equatorial trade winds..

I'm not a cloud expert, and I may be describing this particular uncertainty inaccurately, but I use this as one example, and (unless this aspect of the science has changed in recent months) I believe that one aspect of uncertainty has to do with these clouds and their ultimate net effect as the atmosphere warms.

«While low clouds have a predominantly cooling effect due to their shading of sunlight, most cirrus clouds have a net warming effect on the Earth,» Spencer said.

This is what I get out of it: the Arctic - ice - albedo situation is more complicated than earlier thought (due to clouds, sun - filled summers, dark winters, etc), but NET EFFECT, the ice loss and all these other related factors (some negative feedbacks) act as a positive feedback and enhance global warming.

# 92 Spencer el al 2007 paper doesn't really support the precise mechanism proposed by Lindzen for Iris effect, but more simply observes a strong TOA negative correction associated with warming events at 20 ° S - 20 ° N (that is: in the 2000 - 2005 period of observation, the most significative warming episodes of the surface + low troposphere — 40 days or more — leads to a negative SW+LW cloud forcing at the top of the atmosphere).

If water (rain, clouds, oceans) is the stabilizer, then it should overwhelm any warming by trace gases, albedo effects of glacial advances and retreats, etc..

Spencer + Braswell have shown that over the tropics on a shorter - term basis, the net overall feedback from clouds with warming is negative; this is largely due to an increase in reflection of incoming radiation by increased clouds with a smaller effect from the reduction of energy trapping high altitude clouds, which slow down outgoing radiation by absorbing and re-radiating energy.

CLOUD's genesis is in the mid-1990s, when space physicist Hendrik Svensmark hypothesized that cosmic rays as mediated by solar effects, play a very large role on the physics of climate, and could explain the warming and cooling trends.

His research looked at cause and effect of clouds and warming.

But I discovered missing a lot information about the quantitative effect of the warming due to clouds.

Contrary to the analysis of a majority of studies, his found that for the past decade, variations in clouds seemed more a cause of warming than an effect.

Stuart L I am a stupid layman, but wonder about the effects of water vapour (clouds) when I lived in the UK cloud conditions would cause the temps to be milder (warmer) here in Philippines cloud causes cooler conditions, how can one calculate the overall effect on the earths surface?.

These models suggest that if the net effect of ocean circulation, water vapour, cloud, and snow feedbacks were zero, the approximate temperature response to a doubling of carbon dioxide from pre-industrial levels would be a 1oC warming.

The film continues to consider the argument in The Great Global Warming Swindle connecting the effect of solar flux on cosmic rays, and cloud formation.

Its warming effect, however, is simultaneously amplified and dampened by positive and negative feedbacks such as increased water vapor (the most powerful greenhouse gas), reduced albedo, which is a measure of Earth's reflectivity, changes in cloud characteristics, and CO2 exchanges with the ocean and terrestrial ecosystems.

''... the warming is only missing if one believes computer models where so - called feedbacks involving water vapor and clouds greatly amplify the small effect of CO2.»

The overall effect of the high thin cirrus clouds then is to enhance atmospheric greenhouse warming.

Thus, while the net radiative effect of clouds is that of warming (cooling) across the tropics during La Niña (El Nino) events, the magnitude is quite small and varies greatly from one event to another..»

In addition, the larger amount of open water leads to more moisture in the air, which affects the formation of clouds that have their own effect on warming, either enhancing or reducing it.

He added that certain processes, such as how clouds will respond to changes in the atmosphere and the warming or cooling effect of clouds, are uncertain and different modeling groups make different assumptions about how to represent these processes.