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Thank you for this. Interesting reading.
I was in one blizzard, [URL="http://en.wikipedia.org/wiki/Great_Blizzard_of_1978"]Great Blizzard of 1978.[/URL] I never knew the wind could blow so hard in winter and be so cold. Highway departments were using bulldozers to remove snow from roadways. A nearby U.S. Army facility stuck a tank on a main highway, and then stuck a tank retriever trying to free the tank. Side roads were cleared with front-loaders. They were scooping up the snow and dumping it over fence-rows. Near my fathers' home, the piles of snow were 30 feet high; a continuous wall on both side of the road. It was six weeks before things began to return to normal because of a bitter cold February where nighttime low temperatures were averaging -10°F and daytime was never above 15°F. :smile: [i][Moderator note: Please cool it with the all-bold, storm - no need to shout. We're all about quality of content here.][/i] |
[url]http://www.bbc.co.uk/blogs/dailypolitics/andrewneil/2010/01/the_dam_is_cracking.html[/url]
[QUOTE]Then at the weekend another howler was exposed. The IPCC 2007 report claimed that global warming was leading to an increase in extreme weather, such as hurricanes and floods. Like its claims about the glaciers, this was also based on an unpublished report which had not been subject to scientific scrutiny -- indeed several experts warned the IPCC not to rely on it. The author, who didn't actually finish his work until a year after the IPCC had used his research, has now repudiated what he sees has its misuse of his work. His conclusion: "There is insufficient evidence to claim a statistical link between global warming and catastrophe loss." Yet it was because of this -- now unproved -- link that the British government signed up to a $100 billion transfer from rich to poor countries to help them cope with a supposed increase in floods and hurricanes.[/QUOTE] Caveat: which author? |
Contributions of Stratospheric Water Vapor
[url]http://www.sciencemag.org/cgi/content/abstract/science.1182488[/url]
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[QUOTE=__HRB__;203629][url]http://www.sciencemag.org/cgi/content/abstract/science.1182488[/url][/QUOTE]
Interesting ... the sign of the claimed effect (less stratospheric moisture --> lower rate of increase in global surface temperature) is opposite what I would've guessed on first thought. Note that it appears that none of the major GCMs yet account for this effect, otherwise I would've expected some mention of how the observed trends compare to the various model predictions. (if anyone here has access to the full article, do be so kind as to tell us if thew article mentions implications-for/comparisons-with the numerical models. In politico-climatological news: [url=http://www.aolnews.com/world/article/bin-laden-lashes-out-at-us-on-climate-change/19337366]Bin Laden Lashes Out at US on Climate Change[/url]:[i]Osama bin Laden has lashed out at the U.S. and all industrial nations for causing climate change, saying ending global dependence on the American dollar would be the way to solve the problem.[/i] [quote]In a brief audiotape aired on Al Jazeera television, bin Laden blamed the West for causing hunger and other disasters across the globe, and said the danger of climate change was "not an ideological luxury but a reality." "We should refrain from dealing in the U.S. dollar and should try to get rid of this currency as soon as possible," as well as boycott American goods, he added, saying such actions would have "a huge impact." "This is a message to the whole world about those responsible for climate change and its repercussions -- whether intentionally or unintentionally -- and about the action we must take," the al-Qaida leader said on the tape, the second by him to be released in a week. But he singled out the U.S. for the biggest responsibility, saying that while major industrial nations had agreed to the 1997 Kyoto Protocol curbing emission of harmful gasses, former President George W. Bush had dismissed the agreement to placate big business. On ending reliance on the U.S. dollar, bin Laden said, "I know this has great consequences and grave ramifications, but it is the only means to liberate humanity from slavery and dependence on America," The Associated Press said in a report from Cairo, Egypt.[/quote] [i]My Comment:[/i] He`s apparently still miffed at not being an invited speaker in Copenhagen ... get over it,buddy, that's what happens when you go way over your 15 minutes of allotted time at one conference after another. |
[QUOTE=ewmayer;203720]Interesting ... the sign of the claimed effect (less stratospheric moisture --> lower rate of increase in global surface temperature) is opposite what I would've guessed on first thought.[/QUOTE]
I'm curious why you would have guessed that, given that water vapor is a greenhouse gas? |
[QUOTE=philmoore;203733]I'm curious why you would have guessed that, given that water vapor is a greenhouse gas?[/QUOTE]
I expected - again, this is just based on first-glance guessing as to the sign of the feedback effect - H2O to make more of a GG contribution in the troposphere ... in the upper atmosphere I expected reduced H20 would result in more radiation penetrating to the troposphere. Illustrates why one needs to properly model the physics at all atmospheric levels to capture the often-competing effects due to a change in a concentration of a single atmospheric component. |
[quote=ewmayer;203738]in the upper atmosphere I expected reduced H20 would result in more radiation penetrating to the troposphere.[/quote]Huh? The primary long-wave flux is from the surface upwards, which the GHGs intercept and re-radiate (some downwards, thus global warming). Sunlight is weak in longwave IR, and the GHGs are mostly transparent where sunlight is most intense (it peaks in the mid-visible).
So why would you expect "more radiation" [I'm presuming you mean global-warming-relevant radiation, i.e., IR] "penetrating to the troposphere" as a result of reduced H[sub]2[/sub]O above the troposphere, other than the teensy insignificant (compared to ground-originated longwave IR) bit of longwave sunlight? (What I'm getting at is that IR is a relatively minor proportion of total solar radiation coming to Earth from space, but a major proportion of what Earth's surface radiates upward. Upward radiation peaks in the IR; sunlight doesn't. This is related to the respective black-body spectrum and equivalent temperatures of Sun and Earth.) |
[QUOTE=cheesehead;203764]Huh? The primary long-wave flux is from the surface upwards, which the GHGs intercept and re-radiate (some downwards, thus global warming). Sunlight is weak in longwave IR, and the GHGs are mostly transparent where sunlight is most intense (it peaks in the mid-visible).
So why would you expect "more radiation" [I'm presuming you mean global-warming-relevant radiation, i.e., IR] "penetrating to the troposphere" as a result of reduced H[sub]2[/sub]O above the troposphere, other than the teensy insignificant (compared to ground-originated longwave IR) bit of longwave sunlight?[/QUOTE] I'm talking about total incoming solar radiation which does not get bounced back into space by "stuff" in the upper atmosphere. H2O in the upper atmosphere can potentially have very disparate effects depending on whether it is acting more as a GHG or (if a significant fraction of it condenses into stratospheric clouds) a simple reflector. |
[quote=ewmayer;203769]I'm talking about total incoming solar radiation which does not get bounced back into space by "stuff" in the upper atmosphere. H2O in the upper atmosphere can potentially have very disparate effects depending on whether it is acting more as a GHG or (if a significant fraction of it condenses into stratospheric clouds) a simple reflector.[/quote]Okay. H[sub]2[/sub]O easily transforms from GHG to high-visible-albedo liquid/solid.
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[QUOTE=cheesehead;203780]Okay. H[sub]2[/sub]O easily transforms from GHG to high-visible-albedo liquid/solid.[/QUOTE]Pretty much what has happened at Venus. Most of the water is long gone but the small percentage which remains is stabilised by SO[sub]2[/sub] to form H[sub]2[/sub]SO[sub]4[/sub] droplets which themselves produce high-albedo clouds. The albedo is so high that, despite Venus being closer to the Sun than we are, less incident solar radiation reaches the Venusian lower atmosphere than it does on the earth.
This effect must explain why Venus has a so much lower greenhouse effect than the earth. Paul |
Not what I had in mind, but I'll wait for more explanation by Ernst.
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