Global Dimming: Have We Underestimated Global Warming Because Of It?

[RestoreGore]

http://www.globalissues.org/EnvIssues/GlobalWarming/globaldimming.asp

Global dimming is a dangerous phenomenon sparked by the use of aerosols, airplane contrails, and other chemicals that may have led scientists to actually underestimate the affects of global warming. Now that many countries especially in Europe have been cleaning up pollutants, temperatures have been increasing at an alarming rate. Could one be connected to the other? I think it is worth discussing, especially regarding the affects of anthropogenic climate change we are seeing excelerating at this time in relation to the decrease in other pollutants. I do not believe however, that I have ever heard Al Gore speak of the possibility of global dimming in regards to temperature increases now in his presentations and I really wish he would do so. I think that to mitigate the pollutants that may cause global dimming without addressing the burning of coal, oil, and other fossil fuels that cause global warming leaves us with a grave imbalance and not much time to save this planet for the future.

http://video.google.com/videoplay?docid=1027879546389218797&q=An+inconvenient+truth

As this video by the BBC shows, it is frightening, though some might believe a bit too fatalistic. That is for the viewer to decide.

http://www.realclimate.org/index.php?p=105

More regarding this phenomenon.

Pledge To Be A Climate Messenger

[iamjoy]

1. Global Cooling

supposedly, the chloroflourocarbons reflect light and heat back into the atmosphere. In the 1970's the biggest climate change theory was that we were heading for another ice age. We also realized how bad cloroflorocarbons were for the air we breathe.

We cleaned up the CFs which is good in so many ways, but it does make global warming worse.

[Harper_is_Bush]

2. "In the 1970's the biggest climate change theory was ice age"

You've been hoodwinked by the global warming deniers.

The 1970's "theory" of an oncomming ice age was never more than a minor musing by a few scientists. It was never a "big" theory, and never gained any traction. In fact, I don't believe there is a single peer-reviewed paper that supported it.

The story has become big now because it's convenient to global warming denial.

[RestoreGore]

5. I haven't been hoodwinked by anyone

As I understand it, global warming now will be even WORSE than suspected because of the mitigation of these aerosol pollutants. I am stating that the climate crisis is even worse than is being predicted because we continue to spew fossil fuels into the air. I am not denying anything, and I sure as hell don't listen to global warming deniers. I can think for myself. I am speaking of a BALANCE here. Cleaning up pollutants without balancing it by lessening the impact of greenhouse gases may well have brought us to the tipping point already NOW. I'm not in the seventies.

[Harper_is_Bush]

9. good grief, pay attention to who is replying to whom. n/t

[The Traveler]

8. Well, it was more complicated than that

There was a lot of debate between the "freeze over" vs "burn up" crowd ... I was a physics student in those days and several of my profs were directly involved in this work. (Studied thermo under Joe Ford, one of the "fathers of chaos theory".) Anyway, models were crude and all the data really showed was that some sort of effect was inevitable.Successful implemntation of clean air standards certainly had an impact ... but those standards helped reduce reflective materials without addressing green house gases.

Recently it has been suggested we seed the upper atmosphere with sulfer (?) to reflect light and moderate climate change thereby. Well, I'm sceptical we can predict or manage all the side effects of THAT.

[sofa king]

17. The closest thing to an article I read about that idea was...

A rather tounge-in-cheek article in Analog Science Fiction, which attempted to make the case that the burn-off of European forests staved off the Little Ice Age, and the Petroleum Era counteracted a similar cold snap in the late 1800s.

However, I saw that little 5000 word article cited by global warming opponents as recently as five years ago.

[RC]

12. Correction

Ozone: The gas formed of three bounded oxygen atoms. In the upper atmosphere sufficiently energetic solar photon break apart oxygen molecules; then ozone it is formed by oxygen molecules combining with the free oxygen atoms. It is also naturally formed by lightning.
Ozone blocks ultraviolet radiation.
Cloroflorocarbons: industrial chemicals that catalyze the breakdown of ozone in the upper atmosphere.
Ozone hole: A region in the upper atmosphere over the Antarctic continent that is unusually depleted of atmospheric ozone.

[msongs]

3. a PBS "Nova" broadcast talked about this for an hour long show nt

[Ilsa]

4. An Inconvenient Truth was finally available at the movie place

I patronize. Great to see it. They only had about 4 copies, but I was happy to see that they were all out last weekend, even if it meant I had to wait a little longer. ASide from freepers, I guess I'm the last person to get to watch it. i was really impressed. and frightened for my children and the future.

[FedUpWithIt All]

6. I read something about this a couple of years ago.

It concerned me a lot because it would mean the more we reduce these types of emissions the more heat from the sun will be trapped. This is why i have long believed the projections are WAY off.

[RestoreGore]

7. I think the projections are off too

I think we have less than ten years before that window closes.

[FedUpWithIt All]

10. I have just been trying to mentally and physically prepare myself for whatever...

We really don't know what will happen but the idea that the projections tend to consider only certain factors, rather than a whole picture (assuming we could even anticipate what that might be), does not inspire much confidence.

I just worry that less is being done to try and correct the problems as a result. It is human nature to react when faced with a more immediate threat, rather than some distant possibility.

[OKthatsIT]

11. Let's ask Rep Dennis Kucinich to reintroduce the "Space Preservation Act"

The "Space Preservation Act of 2001" originally introduced in the House by Rep. Dennis Kucinich as HR 2977 has been re-written.

http://www.fas.org/sgp/congress/2001/hr2977.html

The new, revised bill, HR 3616, "Space Preservation Act of 2002" was introduced January 23, 2002.

http://www.fas.org/sgp/congress/2002/hr3616.html

[Mojorabbit]

13. I just watched it

Damn. I don't think we have the technology available to perfectly time a decrease in pollution with a decrease in greenhouse gases. The balance is so intrictate. A lot of people will suffer.

[dipsydoodle]

14. You don't have to look far

to acknowledge the effects of global dimming. During the 2 days following 9/11 you had no air traffic. Your average temperatures in the absense of contrails, measured across all of your weather stations , rose by 1 degree .

[kestrel91316]

15. See??? We need to spew MORE crap into the air, not less!!!

I knew Rush was right!!!!!!!!

[GliderGuider]

16. Jesus Haploid Christ!

What a stunning movie.

That's the first time I've seen Global Dimming and it's implications laid out and connected. I was already a deep pessimist just from understanding Peak Oil with a bit of Global Warming thrown in. Now this. It just adds one more skein to the Gordian Knot we have woven for ourselves, and makes the possibility of a good outcome seem even more remote.

Humanity is twice too clever and not half smart enough for its own good.

What a freaking mess.

On edit:

OK, I went and read the RealClimate article and comments, so I'm a bit calmer now. The science is still coming in, and the TV story was written, edited and produced for maximum impact. However, this is yet one more datum on my personal internal graph - the one that tells me that every time we find out something new about the climate, it's always that the news has gotten worse. We appear have a lot yet to discover about exactly how we have inadvertently doomed our species.

It's still a freaking mess.

[Dogmudgeon]

18. We have underestimated *everything*

And the main thing we've underestimated has been our ignorance of what we're doing.

It's like the "controversy" over whether we're headed for a "waterworld" era or a new ice age. Either scenario will be bad news. Either would happen as a result of anthropogenic modification of the atmosphere, the climate, and the entire ecology of the Earth. And due to the complexity of the climate, we can't be sure exactly what we'll get other than "something different". Maybe real different.

For example, most of us were thinking that this past summer would be about as bad for hurricanes as the summer of 2005. We didn't count on the presence of high-altitude shear winds, which is yet another manifestation of climate change. We were wrong about the details, but right about the problem.

I'm still an "advocate" of the new ice age idea, and think we'll see the climate "snap back" within about 10-50 years. On the other hand, I could easily be wrong, and we could be in for two or three hundred years of abnormally high temperatures. Either way, it supports my underlying idea that we've thrown the climate out of balance, and probably at a critical time in geoclimate history, too.

One factoid I regularly present is that many, if not most (if not all) Heinrich Events (cooling/little-ice-age) have been preceeded by a dramatic warming spike. In one case, I believe the spike was estimated from proxy data at over 50°F. We could see 90°F temperatures in NYC and Paris in, for instance, January of 2020, and then, on the other side of a cooling snap, see summer snowstorms in Florida and Lebanon in July of 2028. We were 2/3rds of the way there on the NYC/Paris forecast this week. It was similar in its extreme to a 50°F day in Florida in July.

Unlike the scenario in The Day after Tomorrow, those kinds of extremes will not cause the deaths of half the world's people. What WILL cause the deaths of half the world's people will be the loss of predictable agriculture -- something that could happen in any number of climate-change scenarios -- and all scenarios of un-planned-for Peak Oil.

The possibility that the climate could swing from one extreme to the other is attractive to the climate change "skeptic". They will get to have their cake and debunk it, too; in no given year will they be without a snappy comeback, a tart cocktail party quip, or a blog "bwa-ha". They can repeat their favorite mantra, "The Science! The Science!" and convince everyone that they are fighting for rational thought itself. And the fact that similar climate changes have happened in the past, before industrialization, will allow them to crack wise that this is something entirely natural.

Natural? Well, so is death, whether at age 105 from age-related vascular system failure during sex, or at age 28 from starvation and hypothermia during influenza.

In many respects, I am a pessimist. I do not think we've got ten (or five or twenty) years before we pass the point where our efforts to stop an age of ice or fire are futile. I think we passed it some time ago, perhaps as long ago as the 1970s, during the last (less intense) ripple of strange weather we experienced. However, we DO have the power to make the coming era a challenge rather than a human die-off (from a number of confluent problems). Indeed, we have our choice of one among any number of futures. Which of them do we want to be ours?

--p!