Sentences with phrase «albedo decreases»

Because each process responds positively to warming (i.e., albedo decreases as warming increases), they are all likely to become increasingly important in the future.

The main cloud bands move more poleward to regions where solar insolation is less intense so total global albedo decreases.

When the oceans are cold and frozen it snows not enough and albedo decreases.

When oceans are cold, it snows less and Albedo decreases.

For instance, Han et al. (1998) showed that cloud albedo decreases with decreasing droplet size for the optically thinner clouds over the oceans.

So for example deglaciation warmed global mean temps by about 5 C over 10k years with a radiative forcing of about 6.5 W / m2 (total of both GHG increases and albedo decreases).

Oh, but a simpler idea: what if asteroid dust single scatter albedo decreases from visible to solar IR?

• albedo decreases as ice melts (ice is perhaps 80 % reflective, while ocean albedo can be as low as 3.5 %) • increased water vapor in a warmer climate • warmer oceans absorb less carbon dioxide • warmer soils release carbon dioxide and methane • plants in a hotter climate are darker

«Scientists have talked about Arctic melting and albedo decrease for nearly 50 years,» said Ramanathan, a distinguished professor of climate and atmospheric sciences at Scripps who has previously conducted similar research on the global dimming effects of aerosols.

Here's an example of your general illogic: Suppose we had a time period in which the planet's albedo decreased (fewer clouds or aerosols, let's say) but the average surface temperature of the planet also decreased.

A typo in mine at # 25 is where 40,000 m3 should read 400,000 m3, and an addendum is the reference for the forcing from the Albedo Loss feedback shown in the satellite record: «Observational determination of albedo decrease caused by vanishing Arctic sea ice» See: http://eisenman.ucsd.edu/publications/Pistone-Eisenman-Ramanathan-2014.pdf

The Amazon and other rainforests drying out The Siberian bogs (the size of germany, france and the UK combined) start to release methane in accelerating annual volumes Ice Albedo decreasing Ocean conveyor (thermohaline systems to some) weakening due to freshening of the seas

With regard to Dr Tobis» observation that: «there's a something on the order of a 10 % chance that we may have already passed the 2 C mark by any reasonable definition» the evidence of a study of Albedo Loss published last January appears to put the issue beyond doubt: «Observational determination of albedo decrease caused by vanishing Arctic sea ice» (Kristina Pistone, Ian Eisenman, and V. Ramanathan)

As a result the Earth's global albedo decreased by the equivalent of around — 5 W / m ^ 2, i.e. decrease of reflected SW radiation (= heating of our planet).

Project Earthshine shows the albedo decreasing to 1998 and then increasing since perfectly matching the end of global warming in 1998 and the start of cooling after 1998.

«The decrease in Earth's reflectance from 1984 to 2000 translates into an albedo decrease equivalent to a forcing of 6.8 W / m ^ 2.

How much it has grown is not stated in the paper: «Observational determination of albedo decrease caused by vanishing Arctic sea ice» http://eisenman.ucsd.edu/publications/Pistone-Eisenman-Ramanathan-2014.pdf but it seems very clear that Arctic sea - ice loss is in accelerating decline towards zero in the coming decades, meaning that this forcing will rise very substantially along with those from land - ice and snow cover decline.

However, if we cross off the oddballs here, we see that the second tier of the tree decomposes to just three mechanisms, solar irradiance increase, albedo decrease, and heat reservoir release.

Rather, an albedo decrease (3.4 W / m ² to 6.8 W / m ²) was driving the warming for the period in question.

I have issues with the second tier where albedo decrease is lumped in with CO2 effects.

An albedo decrease of only 1 %, bringing the Earth's albedo from 30 % to 29 %, would cause an increase in the black - body radiative equilibrium temperature of about 1 °C, a highly significant value, roughly equivalent to the direct radiative effect of a doubling of the atmospheric CO2 concentration.

«Scientists have talked about Arctic melting and albedo decrease for nearly 50 years,» said Ramanathan, a distinguished professor of climate and atmospheric sciences who has previously conducted similar research on the global dimming effects of aerosols.

With respect to Judith Curry: I will ask her to give references to better underpin her claims (for example on the claim that albedo increase on land due to more snow is compensating for the albedo decrease above the arctic sea).

Eric mentioned the «Observational determination of albedo decrease caused by vanishing Arctic sea ice» study, here more data:

Observational determination of albedo decrease caused by vanishing Arctic sea ice.

Perovich has done lots of data collection which shows the effects of surface melt ponds on albedo, as also shown by Pistone et al. in figure 3 of their recent PNAS paper: «Observational determination of albedo decrease caused by vanishing Arctic sea ice».

Averaged over the globe, this albedo decrease corresponds to a forcing that is 25 % as large as that due to the change in CO2 during this period, considerably larger than expectations from models and other less direct recent estimates.

Cloud amount and albedo decreased over mid-latitude oceans in both hemispheres (especially over the North Atlantic), over the southeast Indian Ocean, and in a northwest - to - southeast line stretching across the central tropical South Pacific.»

Not exact matches

These factors have decreased the region's albedo, or the fraction of incoming light that Earth reflects back into space — a change that the CERES instruments are able to measure.

The team's computer simulations suggested that the soot can cause a decrease of between 1.6 and 4.1 percent in the glacier's albedo — a measure of its sunlight - reflecting «whiteness» — and that the resulting heating can cause up to a 24 percent increase in the annual snowmelt, Yasunari reported here Monday at a meeting of the American Geophysical Union (AGU).

The surface's reflectivity, which scientists call albedo, could decrease by as much as 10 percent by the end of the century, the study finds.

Also about the ice - albedo feedback within 1K temperature oscillation the albedo will change of, let us say, 10 %, so for an increase of 1K the albedo will decrease from A = 0.3 to A = 0.27.

I guess I am surprised that with better understanding of the importance of water vapor feedback, sulfate aerosols, black carbon aerosols, more rapid than expected declines in sea ice and attendant decreases in albedo, effects of the deposition of soot and dust on snow and ice decreasing albedo, and a recognition of the importance of GHGs that were probably not considered 30 years ago, that the sensitivity has changed so little over time.

[Response: weaker cosmic ray flux - > fewer low clouds - > decrease in sunlight reflected back to space), then you need to explain why the night temperatures appear to increase faster then day temperatures (for any amplification mechanism involving te albedo, you'd expect the opposite, as there is no sunlight to reflect on the dark side of the planet...).

Unless low - level cloud albedo substantially decreased during this time period, the reduced solar absorption caused by the reported enhancement of cloud cover would have resulted in cooling of the climate system that is inconsistent with the observed temperature record.»

As ice melts and ice area decreases, the albedo feedback will amplify global warming.

A journalist from Jyllands Posten present at the conference got the message, as my criticism was echoed in a news report the following day («Klimaforskere i åben krig» [translation «Climate researchers in open war»], May 28, 2002): It's tricky to explain how a warming caused by decreasing albedo would be stronger at the night - side (dark) of the planet.

Melting ice / snow = > decrease in albedo.

[1] CO2 absorbs IR, is the main GHG, human emissions are increasing its concentration in the atmosphere, raising temperatures globally; the second GHG, water vapor, exists in equilibrium with water / ice, would precipitate out if not for the CO2, so acts as a feedback; since the oceans cover so much of the planet, water is a large positive feedback; melting snow and ice as the atmosphere warms decreases albedo, another positive feedback, biased toward the poles, which gives larger polar warming than the global average; decreasing the temperature gradient from the equator to the poles is reducing the driving forces for the jetstream; the jetstream's meanders are increasing in amplitude and slowing, just like the lower Missippi River where its driving gradient decreases; the larger slower meanders increase the amplitude and duration of blocking highs, increasing drought and extreme temperatures — and 30,000 + Europeans and 5,000 plus Russians die, and the US corn crop, Russian wheat crop, and Aussie wildland fire protection fails — or extreme rainfall floods the US, France, Pakistan, Thailand (driving up prices for disk drives — hows that for unexpected adverse impacts from AGW?)

The resulting decrease in albedo then warms the atmosphere.

Calculations as to the magnitude of this effect (that is, how dust is needed to significantly decrease glacier albedo) certainly have been done, though probably not on a global basis.

That is, by decreasing the (rather high) Bond albedo of Earth one could increase rate of entropy production, which is inconsistent with a MEP state.

For example, [Kruss 1983] has this to say about the Lewis glacier on Mt. Kenya: «A decrease in the annual precipitation on the order of 150 mm in the last quarter of the 19th century, followed by a secular air temperature rise of a few tenths of a degree centigrade during the first half of the 20th century, together with associated albedo and cloudiness variation, constitute the most likely cause of the Lewis Glacier wastage during the last 100 years.»

I guess I am surprised that with better understanding of the importance of water vapor feedback, sulfate aerosols, black carbon aerosols, more rapid than expected declines in sea ice and attendant decreases in albedo, effects of the deposition of soot and dust on snow and ice decreasing albedo, and a recognition of the importance of GHGs that were probably not considered 30 years ago, that the sensitivity has changed so little over time.

What is more we know with certainty that there are significant positive feedbacks — water vapor, decreased albedo, etc..

According to the skeptics, the solar irradiance isn't very important, it is the strength of the sun's magnetic field (that allows or stops cosmic rays from coming in which then causes more or less clouds, which increases or decreases the Earth's albedo, which then causes warming or cooling of the Earth's surface).

On the possibility of a changing cloud cover «forcing» global warming in recent times (assuming we can just ignore the CO2 physics and current literature on feedbacks, since I don't see a contradiction between an internal radiative forcing and positive feedbacks), one would have to explain a few things, like why the diurnal temperature gradient would decrease with a planet being warmed by decreased albedo... why the stratosphere should cool... why winters should warm faster than summers... essentially the same questions that come with the cosmic ray hypothesis.

There is also the issue of increased biological activity in melt ponds decreasing albedo (beyond that of the melt ponds themselves).

This positive climate feedback is greater than expected from the additional forcing alone, due to amplification by reduced surface albedo through melting of continental snow and decreased sea - ice coverage, especially in the wintertime.

The resulting increased / decreased ice is amplified by «various feedbacks, including ice - albedo, dust, vegetation and, of course, the carbon cycle which amplify the direct effects of the orbital changes.»