Greenhouse theory smashed by biggest stone [meteorite, not human emissions]

PhysOrg.com ^ | 13 March 2006 | Staff

[editor-surveyor]

"This -- if it proves out -- should throw the environmentalists into a tizzy."

Or it could be their greatest empowerment: an excuswe to tax and control water.

[editor-surveyor]

Which reminds me - whatever happened to the "small comets" hypothesis?

That's just one more area of research that has been essentially smothered due to it's ability to demolish any "old earth" hypothesis. If it is real, then by the end of 100,000 years or so there would be five times as much water on earth as there is now.

[beezdotcom]

That's just one more area of research that has been essentially smothered due to it's ability to demolish any "old earth" hypothesis. If it is real, then by the end of 100,000 years or so there would be five times as much water on earth as there is now.

I strongly doubt that is why it's been "smothered". There would certainly be some "old earth" grant money in hypothesizing where all the extra water might have gone. I suspect Hillary's thighs.

[RegulatorCountry]

"Al Gore must be spinning in his grave."

Nah, just lightly pirouetting in his play-Whitehouse in Tennessee.

[El Gato]

Um, didn't we intentionally denotate at least that much in the 1950s? Between China, The USSR, and the US, I would think that we easily blew up 100 MT of stuff in a 20 year period.

The author mentions these tests. In fact he credits them with temporarily stopping the planetary temperature rise. The figures showing this are in his paper They were not at as high an altitude, most were surface or subsurface detonations and most were not nearly so large individually. (the largest was bigger however, the Soviets did a one time demonstration of 50 MT, which was detonated at 4 km altitude)

[El Gato]

The author that the difference is the level at which the disturbance occurred. Volcanoes and even nuclear tests don't occur at 10 Km altitude. Read it here

[El Gato]

Both would place particulates high in the atmosphere,

But not so high as the Tunguska event, which is estimated at 10 km for the center of the explosion. Although it's the effect on the water vapor in the troposphere and mesosphere that the author argues is different between the volcanoes and nuclear tests on the one hand, and the Tunguska event.

He also argues that the effect is at permanent, or at least of longer lasting effect than events lower in the atmosphere.

[El Gato]

It is really all the contrails of high alititude airliners injecting water vapor at a critical altitude, where it accumulates and retains more heat for the earth...

Actually the author indicates the critical altitude is somewhat higher. If anything, the ice crystals injected by the airlines would have a cooling effect, but they also would settle out fairly rapidly.

[El Gato]

This link has been pulled. Guess they didn't want contrary opinions getting in the way of their funding.

Worked for me, almost two weeks later.

[Smokin' Joe]

From the paper linked in the posts above:

When a nuclear charge explodes at the Earth’s surface or in the atmosphere, the shock wave vents water vapor from the troposphere to the stratosphere through tropopause.

For some period (approx. 3 years) water vapor in the stratosphere and aerosol, and dust in the troposphere and stratosphere suffice for the defense of the Earth from solar radiation. But then all gradually settled, and global warming continued.

All nuclear explosions above the ground and the sea together gave rise to tendency for decreasing the global temperature of Earth’s surface. The last nuclear test in open atmosphere was on the 16th October 1980.

Interesting.

If the Tunguska event was an exploding meteorite (or even a comet), and the explosion pushed water vapor higher up or even added some of its own to the mix, then according to the paper, the conclusion could be drawn that atmospheric nuclear testing is all that has interrupted a linear trend in temperature increases since 1908.

Further the conclusion could be drawn that the cause of the warming is not human, or even necessarily solar activity (although that may be a factor), but the Tunguska event and the associated displacement of water vapor. Hmmmmm.

[Sundog]

I'm much more inclined to think the lessening magnetosphere around the earth is letting more particles through, yielding additional heating, but the spirit of the thread was more toward possible junk science theories than anything.

[El Gato]

I'm much more inclined to think the lessening magnetosphere around the earth is letting more particles through, yielding additional heating,

I can't imagine that the additional particles carry all that much energy.

What's needed is something that changed or changes the feedback loops that keep the temperature stable. And it needs to be either a persistent change, or be renewed.

[El Gato]

He must have considered this in his calculations, but once again the coverage doesn't mention such an obvious detail!

The coverage of any scientific subject often leaves out the more important details on how the conclusion was reached. However, here's a link to the paper itself. He writes:

But water vapour in the mesosphere is another matter. At a pressure hundreds of times less than at atmospheric pressure at sea level, the freezing point of water vapour shifts to a vastly negative temperature without the intermediate liquid state (see Fig. 3). Therefore there exists a sizable layer spanning the higher part of the stratosphere and lower part of the mesosphere where water is in the gas state. The mesospheric composition is slightly distinct from the stratospheric one at significant, with less density of gases. The gaseous state of water vapor has lower density than the ambient gases (atomic masses of H2O, O2, and N2 equal 18, 32, and 28, respectively). Therefore it has some tendency to move up in rapidly moving flows with some stirring against the background of diffusion. When it migrates, gas climbs to a temperature below freezing point, crystallizes and migrates down. There it evaporates missing the liquid state, and the process repeats. Thus, mesopause with a strongly negative temperature of around -95o prevents water vapor leaving beyond the upper bound of the mesosphere.

He's clearly not talking about just ice crystals, or just condensed liquid water, but rather water vapor as well. He's also talking about considerably higher altitude phenomena than is usually the case when talking about the greenhouse and albedo effects of clouds.

[westmichman]

This is where I got the water vapor idea. Thought you might be interested. I was wrong, it's not water vapor but ice crystals that are the dirty little secret.
PING

[cogitator]

This particular idea has already been addressed here:

http://www.realclimate.org/index.php/archives/2006/03/meteors-nuclear-tests-and-global-warming/

Summary: the idea needs a lot more work.

[westmichman]

I still think the idea that what we are doing is causing global warming is a bunch of garbage designed to destroy capitalism. The sun causes global warming, period. What were the CO2 emissions coming from that caused the glaciers to recede from Michigan?

[cogitator]

The sun causes global warming, period. What were the CO2 emissions coming from that caused the glaciers to recede from Michigan?

Actually, to say that the Sun causes global warming, period, doesn't even characterize the main cause of glacial/interglacial cycles. The main cause of those cycles is Milankovitch forcing, due to variability of the Earth's orbital eccentricity, axial tilt, and axial precesssion. These factors alter the amount of solar insolation the Earth receives (so it's the Earth's fault, not the Sun). Changing solar insolation alters the Earth's radiative balance.

Increasing concentrations of CO2 in the atmosphere in the middle of a stable interglacial period (i.e. now) also alters Earth's radiative balance. The predicted effect of this change is an increase in global temperature.