Has anyone seen or heard about the Intergovernmental Panel on Climate Change’s conclusion, that was reported in the NY Times a few days ago?
According to the Times.
The study is supposed to be released next year. I want to know what’s in it now.
Y’all may now continue your discussion.
Boris B wrote:
Wait a minute? What are we at odds over? My first post was mainly questions; my next post was debunking griffey’s urban legend that Mt. Pinatubo created CFCs, and ripping up griffey’s website for making a lot of misleading statistics; my third post was a link; my fourth post was me wondering aloud if griffey was a troll. Which part do you disagree with?
merckx replies:
I looked back over those posts and they give me the general impression that you believe in the phenomenon, but I admit they are non-committal. Though you do provide a link to the EPA, which I consider an enemy of liberty and a source of disinformation, so I suspect we may be still at odds. But, perhaps I did jump to a conclusion.
Boris B wrote:
I agree with you that more study is needed, and I agree that claims of super-rapid catastrophic global change need to be treated with skepticism. I haven’t
noticed the press ignoring evidence against global warming, since I’ve seen more than one article talking about that very evidence. On the whole, it seems like
we agree more than we disagree. I’m still not going to give people like griffey, who doesn’t know the difference between an element and a compound, a free
ride to dole out misinformation
merckx replies:
I’ve also seen a few articles in the mainstream press, but coverage generally assumes GW is a scientifically supported and accepted reality. Mainstream coverage certainly appears to be out of proportion to credible scientific advocacy. I see most of the anti-warming science quoted in the alternative press (cable TV news, talk radio, Drudge) and it seems the bulk of real science points to no GW phenomenon. If coverage was essentially limited to credible science (rather than political groups, like the idiotic Sierra Club) I doubt the public would consider GW a potential problem, and we would still have freon in our air conditioners and refrigerators.
merckx
AMAZING!!!
According to the information I can find, the mass of the Earth is 5.975 x 10[sup]27[/sup]grams.
Since there are about 9.091 x 10[sup]5[/sup] grams in a ton, that means 10[sup]15[/sup] gigatons is about 9.091 x 10[sup]29[/sup] grams, or over 1000 times the total mass of the world.
These Gas Hydrates must have some interesting properties indeed, if you can find that much of them JUST IN THE OCEANS!
sigh Thank you for the vivid reminder of why I shouldn’t respond to these posts without proofreading first.
From Buffett (2000)*, " … 10[sup]16[/sup] kg of methane carbon appears to be a reasonable order of magnitude estimate, and this value is roughly 3,000 times larger than the amount of methane carbon in the present-day atmosphere."
10[sup]16[/sup] kg of carbon = 10[sup]19[/sup] g of carbon = 10[sup]10[/sup] (metric) gigatons of carbon
Got my kgs fouled up with my gigatons, and was still off an order of magnitude. Hope this clarifies things.
*Buffett, B.A., 2000, Clathrate hydrates: Annual Review of Earth and Planetary Sciences, v. 28, p. 477-507.
Suppose GW takes place, as described previously? How long will it take to melt the greenland icecap? I once read that the cap is over 2 miles thick in places-are we talking decades, centuries, or millenia? What would the interior of greenland be-assume it would be a big lake-as the ice had depressed the surface of the earth.
Fillet wrote:
Nope, you’re still off by a factor of 1,000,000.
10[sup]16[/sup] kg = 10[sup]13[/sup] tonnes (metric tons) = 10[sup]4[/sup] gigatonnes, not 10[sup]10[/sup] gigatonnes.
tracer, you are absolutely correct. I seem to have lost all computational ability in this thread; my apologies for the confusion.
egkelly, at the moment I can’t put my hands on anything specifically related to Greenland ice volume. My old class notes say that if all the remaining glacial ice were to melt (Greenland and Antarctica would be the primary contributors), sea level would rise about 80 meters (roughly 260 feet). Estimates for sea level rise as a result of global warming in the next 100 years run about 1 meter (2-4 feet), depending on your location.
By way of contrast, when ice sheets reached their maximum extent around 21,000 years ago, sea level was nearly 200 meters (650 feet) lower than at present. Melting of the Laurentide ice sheet was most rapid between 14,000 and 11,000 years ago, with a sea level rise of about 55 meters (approx. 1.8 meters, or 6 feet, per century).
And yes, the interior of Greenland would be submerged if all the ice melted rapidly enough, but I think it would produce a very large bay rather than a lake.
Fillet wrote:
This is only true if you assume that all other variables stay constant – including the temperature of the liquid water in the oceans.
If global average temperatures increase enough for the Greenland and Antarctic ice caps to completely melt, the oceans will also thermally expand. In fact, according to a blurb I heard on the Learning Channel (so you know it must be true :rolleyes: ), this expansion will account for a much larger rise in the sea levels than you would get simply by turning the glacial ice into water.
And then, and then, the shift in the distribution of mass around the oceans from polar to elswhere will cause the Earth to tilt further, creating colder climes at the poles, causing all the water to freeze again, causing another ice age, and then more mass at the poles will re-right the Earth, getting warmer sun back to the poles for longer periods, and then, and then…
It’s true that thermal expansion will also have an effect on sea level as the climate warms. It’s not a straightforward calculation, though, because the thermal expansion coefficient of water is influenced by salinity as well as temperature (salinity having the opposite effect of temperature), and both temperature and salinity are regionally variable. The complexities involved in calculating thermal expansion with warming are the reason why most folks focus on the simple addition of water through ice melting.
::shrug:: I don’t think it matters much which mechanism is responsible, or to what degree; once you’re talking sea level rise on the order of 6-10 feet, a whole lot of places will be in trouble regardless. New Orleans, the Netherlands and Bangladesh spring to mind immediately.
I didn’t see this particular Learning Channel blurb, but as I’ve mentioned before in another thread, these programs tend to exaggerate, or at least emphasize the extreme possibilities, so that the program will be more “entertaining.” (Did they mention that thermal expansion affects only the uppermost few hundred meters of the ocean, not the whole thing?)
Math aside…don’t forget that a English ton is a unit of pounds-force (includes gravitational effect) which should not be directly compared to the mass of the Earth.