Political Crossfire Forums

[Winchester]

Quote: "Dimming the Sun" investigates the discovery that the sunlight reaching Earth has been growing dimmer, which may seem surprising given all the international concern over global warming. At first glance, less sunlight might hardly seem to matter when our planet is stewing in greenhouse gases. But the discovery of global dimming has led several scientists to revise their models of the climate and how fast it's changing. According to one recent and highly controversial model, the worst-case warming scenario could be worse than anyone has predicted. "Dimming the Sun" unravels this baffling climate conundrum and the implications for Earth's future.

To find out what global dimming means for the fate of the planet, NOVA reports on the findings of the world's top climate detectives, including an American scientist who found a grim but crucial opportunity immediately following September 11, 2001, when the entire U.S. airline fleet was grounded for three days. This presented a unique opportunity to study the effects of airplane vapor trails on the atmosphere (see The Contrail Effect). Comparing changes in the daily temperature range showed that the absence of dimming from aircraft pollution alone made a marked difference to the temperature. This result hints at how much the effects of atmospheric pollution had been underestimated.

Working in Israel, Dr. Gerald Stanhill was one of the first to discover the surprising fact that less solar energy is reaching the Earth's surface. While his measurements were met with skepticism, a review of worldwide data by Stanhill and a German researcher demonstrated that during the 1980s and early '90s, sunlight reaching Earth's surface had dropped just about everywhere. Halfway around the world, independent studies by Australian scientists confirmed this disturbing diagnosis. (For more, see Discoveries in Global Dimming.)

Scientists have long known that increasing air pollution—the smog that clouds urban skies—endangers our respiratory health. But they had underestimated the impact of pollution on the amount of sunlight reaching Earth. Some scientists now believe that global dimming may also disturb rainfall patterns such as the Asian monsoon. If they are right, global dimming may be one of many factors that contributed to severe droughts and famines in Africa during the 1980s.

The good news is that pollution controls have slowed and possibly even halted global dimming during the last decade. The bad news—and the ironic twist in NOVA's story—is that without pollution, more sunlight is reaching Earth, revealing the full impact of global warming. Although all climate models have important uncertainties, the unsettling implication is that, with dimming fading away in many regions, global temperatures may rise even faster than most models have predicted.

www.pbs.org/wgbh/nova/sun/about.html

Anyone else see this show on NOVA? Really quite interesting. Apparently all the pollution (particles) has somewhat been a counter towards greenhouse gases and global warming. Not sure what to think right now as I'm still trying to digest the show.

[The Impeacher]

Winchester wrote: Quote: "Dimming the Sun" investigates the discovery that the sunlight reaching Earth has been growing dimmer, which may seem surprising given all the international concern over global warming. At first glance, less sunlight might hardly seem to matter when our planet is stewing in greenhouse gases. But the discovery of global dimming has led several scientists to revise their models of the climate and how fast it's changing.

[...]

The good news is that pollution controls have slowed and possibly even halted global dimming during the last decade. The bad news—and the ironic twist in NOVA's story—is that without pollution, more sunlight is reaching Earth, revealing the full impact of global warming. Although all climate models have important uncertainties, the unsettling implication is that, with dimming fading away in many regions, global temperatures may rise even faster than most models have predicted.

www.pbs.org/wgbh/nova/sun/about.html

Anyone else see this show on NOVA? Really quite interesting. Apparently all the pollution (particles) has somewhat been a counter towards greenhouse gases and global warming. Not sure what to think right now as I'm still trying to digest the show.

yes, it was FASCINATING!

we had a thread not unlike this a short while ago:

John Galt is confused by clear air.

this is the so-called "threshold" or sling-shot effect they have been starting to worry about. the net impact of warming could accelerate before we reap the benefits of cleaner air.

my guess is that since we also know "clear air" radiates heat faster, i am hopefully that increased storm activity from the warming may compensate. its going to be a bumpy ride, though....

alternately, it also makes a good argument for a "clean" form of cloud seeding.

it stands to reason, if more energy hits the ground [water], we will have more natural clouds, "clean" clouds.

its also part and partial to why i feel the rain forests are also so important...

[John Galt]

That is what we call "trolling" but in any event, you are confused by evaporation.

[The Impeacher]

John Galt wrote: That is what we call "trolling" but in any event, you are confused by evaporation.

did you see the Nova in question? do you have anything of conent to add to the discussion?

[Winchester]

John Galt wrote: but in any event, you are confused by evaporation.

Don't konw what his views are on evaporation but they actually had an interesting section on evaporation in the show. Evaporation is not determined by temperature like water heating on a stove, but by the amount of sunlight hitting the earths surface.

[John Galt]

The Impeacher wrote: John Galt wrote: That is what we call "trolling" but in any event, you are confused by evaporation.

did you see the Nova in question? do you have anything of conent to add to the discussion?

Yes Impeacher, I had a warning to give to you since you were trolling.

Do not continue.

[The Impeacher]

John Galt wrote: The Impeacher wrote: John Galt wrote: That is what we call "trolling" but in any event, you are confused by evaporation.

did you see the Nova in question? do you have anything of conent to add to the discussion?

Yes Impeacher, I had a warning to give to you since you were trolling.

Do not continue.

That is what i call evasion of the topic, but in any event, you are confused by nature itself.


feel free to demonstrate what i am confused about, or on what the "truth" of the matter is.

[Free Thinkr]

Winchester wrote: Quote: "Dimming the Sun" investigates the discovery that the sunlight reaching Earth has been growing dimmer, which may seem surprising given all the international concern over global warming. At first glance, less sunlight might hardly seem to matter when our planet is stewing in greenhouse gases. But the discovery of global dimming has led several scientists to revise their models of the climate and how fast it's changing. According to one recent and highly controversial model, the worst-case warming scenario could be worse than anyone has predicted. "Dimming the Sun" unravels this baffling climate conundrum and the implications for Earth's future.

To find out what global dimming means for the fate of the planet, NOVA reports on the findings of the world's top climate detectives, including an American scientist who found a grim but crucial opportunity immediately following September 11, 2001, when the entire U.S. airline fleet was grounded for three days. This presented a unique opportunity to study the effects of airplane vapor trails on the atmosphere (see The Contrail Effect). Comparing changes in the daily temperature range showed that the absence of dimming from aircraft pollution alone made a marked difference to the temperature. This result hints at how much the effects of atmospheric pollution had been underestimated.

Working in Israel, Dr. Gerald Stanhill was one of the first to discover the surprising fact that less solar energy is reaching the Earth's surface. While his measurements were met with skepticism, a review of worldwide data by Stanhill and a German researcher demonstrated that during the 1980s and early '90s, sunlight reaching Earth's surface had dropped just about everywhere. Halfway around the world, independent studies by Australian scientists confirmed this disturbing diagnosis. (For more, see Discoveries in Global Dimming.)

Scientists have long known that increasing air pollution—the smog that clouds urban skies—endangers our respiratory health. But they had underestimated the impact of pollution on the amount of sunlight reaching Earth. Some scientists now believe that global dimming may also disturb rainfall patterns such as the Asian monsoon. If they are right, global dimming may be one of many factors that contributed to severe droughts and famines in Africa during the 1980s.

The good news is that pollution controls have slowed and possibly even halted global dimming during the last decade. The bad news—and the ironic twist in NOVA's story—is that without pollution, more sunlight is reaching Earth, revealing the full impact of global warming. Although all climate models have important uncertainties, the unsettling implication is that, with dimming fading away in many regions, global temperatures may rise even faster than most models have predicted.

www.pbs.org/wgbh/nova/sun/about.html

Anyone else see this show on NOVA? Really quite interesting. Apparently all the pollution (particles) has somewhat been a counter towards greenhouse gases and global warming. Not sure what to think right now as I'm still trying to digest the show.
Just saw it tonight, in fact. Proof positive that we don't understand the way our global climate works, IMO. Notice when they first started noticing that there was less surface radiation from the sun, most climatologists disputed that? How in the hell could climatologists not have been on to this very important fact? There's really only one answer, IMO.

The question is "now what," and frankly, no one knows. The one guy saying that we need to do "something" in within a decade; what, exactly? Do without cars and electricity? If it's truly the problem some of them say it is, we might as well concede defeat. We're effed.

[Winchester]

Free Thinkr wrote:
Just saw it tonight, in fact. Proof positive that we don't understand the way our global climate works, IMO. Notice when they first started noticing that there was less surface radiation from the sun, most climatologists disputed that? How in the hell could climatologists not have been on to this very important fact? There's really only one answer, IMO.

The question is "now what," and frankly, no one knows. The one guy saying that we need to do "something" in within a decade; what, exactly? Do without cars and electricity? If it's truly the problem some of them say it is, we might as well concede defeat. We're effed.

That's kind of the conclusion I've come to. If man is contributing to global warming, it'll be too late to do anything to slow it down before were effed. I don't see everyone getting on board with a solution, if in fact a solution can be found, until we're past the point of no return. Our energies will probably be better spent on learning to adapt to any forthcoming changes.

[Free Thinkr]

Winchester wrote: Free Thinkr wrote:
Just saw it tonight, in fact. Proof positive that we don't understand the way our global climate works, IMO. Notice when they first started noticing that there was less surface radiation from the sun, most climatologists disputed that? How in the hell could climatologists not have been on to this very important fact? There's really only one answer, IMO.

The question is "now what," and frankly, no one knows. The one guy saying that we need to do "something" in within a decade; what, exactly? Do without cars and electricity? If it's truly the problem some of them say it is, we might as well concede defeat. We're effed.

That's kind of the conclusion I've come to. If man is contributing to global warming, it'll be too late to do anything to slow it down before were effed. I don't see everyone getting on board with a solution, if in fact a solution can be found, until we're past the point of no return. Our energies will probably be better spent on learning to adapt to any forthcoming changes.
*nods*

Florida s*cks anyhow. :P