Slashdot Mirror

The quantities man put up are staggering compared to any natural production.

Could you please source that statement? Since we've only recently discovered some of the natural sources it does surprise me that we would know anything about the ratio.

Given how CFCs work, if significant natural sources existed then we would have observed a significant ozone hole well before human production of CFCs started up. They're long-life molecules which do not fall out of the atmosphere easily, but we know there was no pre-existing ozone hole before the invention of CFCs and their use in industry.

This is a decent report on the matter: http://downloads.climatescience.gov/sap/sap2-4/sap2-4-final-ch2.pdf

energy prices are climbing precisely when Americans are suffering through the toughest economic times since the 1920s?

I don't see too many of them buying more economical cars, smaller houses or switching off their "security lighting" as a result of this crisis. The USA still has some of the cheapest fuel in the world, how can they not manage?

I know it's tough to believe in global warming in the USA because most of the time GW Bush was in power there were governmental campaigns to obfuscate it (in pretty much the same way the creationists use "teach the controversy" to pretend evolution is still 'unproven') but even they're starting to admit there might be something going on now.

Short version here.

If they are accounted for, why is this news?

Well, actually climate models do account for aerosols and this isn't news.

Until very recently, there was little if any evidence (that was available and analyzed, at any rate) that the troposphere was warming to a degree that matched the greenhouse warming models. Only a few weeks ago did I learn that some relatively recent papers did in fact indicate that the troposphere appeared to be warming in a way that better matched the models. ... Your comment about "overlapping sensitivities" means next to nothing in this context.

And just to save you from pointing out that "this context" isn't what was quoted directly above that, I know. The reason I ignored all the sentences that preceded the statement about overlapping sensitivities is that I'm not saying Liu and Weng did shoddy work or that there are problems with their instruments in particular, so there's no need to recite their validation techniques.

What I'm saying is that all of these remote measurements are subject to larger uncertainties than surface data. The reasons I gave are similar to those on page 6 of this report. I'm merely trying to emphasize that the troposphere debate was due to uncertainties in remote measurements, which still remain larger than surface measurement uncertainties.

Actually, change "multiple factors" to "multiple factors (table 1 on page 5)" and "with no corresponding increase in ozone, no increase in stratospheric methane or water vapor, and no increased solar output" to "with no increase in stratospheric ozone, methane or water vapor, no increased solar output, no volcanic eruptions, and no decrease in well-mixed greenhouse gases"

There are no sinks for CFCs in the lower atmosphere. As a result they are transported to the stratosphere (10 to 50km altitude) where they are broken down by UV radiation, releasing free chlorine atoms which cause significant ozone depletion. In 1998 global atmospheric concentrations of on of the CFCs, CFC-11 was 268pptv. Over the past few decades CFCs 11,12 and 113 have increased more rapidly (on a percent basis) than any other greenhouse gas, but there is now clear evidence that growth rates of CFCs have slowed significantly in the aftermath of the Montreal Protocol (1985) to prevent ozone depletion. In fact, the 1998 atmospheric concentration of CFC-11 was lower than the concentration 5 years earlier. The total forcing value for Chlorofluorocarbons is +0.3Wm-2. This includes CFC-11, 12, 113, 114, 115, methylchloroform and carbon tetrachloride. Under the Montreal Protocol, the production of CFCs 11, 12 and 113 has been successfully phased out since 1995. However, despite these measures, the concentration of CFCs in the atmosphere will remain significant into the next century because of the relatively long lifetimes associated with these compounds.

Good to see that the American Geophysical Union and the National Science Teachers Association have criticized Bush's statements on ID. I wish more scientific and professional organisations would do the same.

I think its a product of having a bean counter as NASA administrator. NASA desperately needs to retire O'Keefe NOW because everyday he stays he is going to drive morale further in to the ground and further crater an agency that is almost past the point of no return. But I shudder to think what kind of loser and sycophant Bush will pick to replace him.

O'Keefe has NO background in aerospace and he has no grasp of what he's doing when it comes to space exploration or aeronautics. Closest he came was a stint as Navy secretary, here is his bio. I think Bush appointed him because he viewed NASA as a management problem to be cleaned up and he wasn't there because he has any vision for making NASA relevent again. As I recall when he arrived, they put NASA on a hard deadline to complete ISS launches, they even created a screen saver counting down the seconds until the next ISS launch deadline and they created an atmosphere where managers sacrificed Columbia because they were so busy obsessing over O'Keefe's bean counter deadline.

To O'Keefe the Hubble is:

- A safety problem

- An untidy accounting problem he needs to zero out

so he's willing to wast hundreds of millions of dollars to do nothing but burn it up in an orderly way.

As for the safety issue that O'Keefe is obesessing over, well you see he is a bean counter not a test pilot, not an engineer, not an astronaut, and he apparently can't cope with risk or danger. When Columbia crashed on his watch it so bent his head that its completely crippled his ability to move forward, and he, with the help of the commission that investigated Columbia has effectively crippled NASA's manned space program. At this point the shuttle can do nothing but fly back and forth to the ISS and then only very carefully and at great expense. The shuttle is essentially no more valuable than the ISS and the ISS has no value anyone can discern in its current crippled configuration and its deadend future.

The dangers of Hubble reentering on its own are wildly overblown. Fact is most its going to burn up and what doesn't is probably going to land in the middle of nowhere, most of the earth being empty. Columbia is a lot bigger than Hubble and it broke up over the U.S. and the debris didn't cause widespread loss of life. It is no more danger than a not particularly large meteor.

Wasting precious resources just to deorbit Hubble is insanity.

You can hold out hope all this will change with the holy grail, the CEV, but just note that the EARLIEST a manned CEV launch will launch is 2014 and that is assuming there aren't massive schedule slips which is the NASA/Boeing/Lockheed wat. That is ten years out just to put a small crew back in to space in a capsule. Apollo put men on the moon in less than ten years using now ancient technology and they were pushing back real frontiers and doing things never done before.

The CEV schedule alone is just completely pathetic. It has all the earmarks of an excuse to funnel large quantities of money in to the pockets of Lockheed and Boeing and never actually fly anything.