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what we knew in 1997

Steve

Well-known member
Over the past century, global measurements of the temperature at the Earth's surface have indicated a warming trend of between 0.3 and 0.6 degrees C. But many - especially the early - computer-based global climate models (GCM's) predict that the rate should be even higher if it is due to the man-made "Greenhouse Effect". Furthermore, these computer models also predict that the Earth's lower atmosphere should behave in lock-step with the surface, but with temperature increases that are even more pronounced

Unlike the surface-based temperatures, global temperature measurements of the Earth's lower atmosphere obtained from satellites reveal no definitive warming trend over the past two decades. The slight trend that is in the data actually appears to be downward. The largest fluctuations in the satellite temperature data are not from any man-made activity, but from natural phenomena such as large volcanic eruptions from Mt. Pinatubo, and from El Niño. So the programs which model global warming in a computer say the temperature of the Earth's lower atmosphere should be going up markedly, but actual measurements of the temperature of the lower atmosphere reveal no such pronounced activity.

So What is Going On?

The atmosphere is extremely complex in its behavior. Because of this, finding the correct explanation for the behavior we observe is complex as well. Virtually all scientists will agree that a doubling of the amount of carbon dioxide in the Earth's atmosphere should have some effect on the temperature of the Earth. But it is much less certain how or if we will recognize the effects of this increase. There are several reasons:

* First, the influence of a man-made doubling of the amount of carbon dioxide in the atmosphere is small compared to the Earth's natural cooling rate, on the order of only a percent.
* Second, there is a much more important greenhouse gas than carbon dioxide, namely water vapor. Water vapor over the Earth is extremely variable, both in space and in time.
* Third, the ways in which clouds and water vapor feed back and ultimately influence the temperature of the Earth are, at best, poorly understood.
* Fourth, while the whole Earth is indeed in a state that scientists describe as "radiative equilibrium," where the incoming sunlight equals the outgoing infrared radiation to provide a roughly constant overall temperature, the surface is far from this radiative balance condition. Evaporation and convection processes in the atmosphere transport heat from the surface to the upper troposphere, where it can be much more efficiently radiated into space since it is above most of the greenhouse-trapping water vapor. So in short, it is this convective overturning of the atmosphere - poorly represented in computer models of global warming - that primarily determines the temperature distribution of the surface and upper troposphere, not radiation balance.
 

Steve

Well-known member
just how bad is our climate change/global warming?

so bad even Jupiter and Mars are effected?

Jupiter's recent outbreak of red spots is likely related to large scale climate change as the gas giant planet is getting warmer near the equator.
http://apod.nasa.gov/apod/ap080523.html

Mars is being hit by rapid climate change and it is happening so fast that the red planet could lose its southern ice cap, writes Jonathan Leake.

Scientists from Nasa say that Mars has warmed by about 0.5C since the 1970s. This is similar to the warming experienced on Earth over approximately the same period.

Since there is no known life on Mars it suggests rapid changes in planetary climates could be natural phenomena.

well as long as the moons are cold and barren we will be fine..
MIT researcher finds evidence of global warming on Neptune's largest moon
CAMBRIDGE, Mass. -- We're not the only ones experiencing global warming. A Massachusetts Institute of Technology researcher has reported that observations obtained by NASA's Hubble Space Telescope and ground-based instruments reveal that Neptune's largest moon, Triton, seems to have heated up significantly since the Voyager space probe visited it in 1989. The warming trend is causing part of Triton's surface of frozen nitrogen to turn into gas, thus making its thin atmosphere denser.

"At least since 1989, Triton has been undergoing a period of global warming. Percentage-wise, it's a very large increase," said Elliot, professor of Earth, Atmospheric and Planetary Sciences and director of the Wallace Astrophysical Observatory. The 5 percent increase on the absolute temperature scale from about minus-392 degrees Fahrenheit to about minus-389 degrees Fahrenheit would be like the Earth experiencing a jump of about 22 degrees Fahrenheit.

well at least on Pluto it really isn't global because it was delisted as a planet..

Pluto is undergoing global warming, researchers find

BIRMINGHAM, Ala.--Pluto is undergoing global warming, Elliot said the new results have surprised the observers, who as recently as July thought that Pluto's atmosphere may be cooling. "From the July data, we knew that Pluto's atmosphere had changed since 1988, but the August data allowed us to probe much more deeply into Pluto's atmosphere and have given us a more accurate picture of the changes that have occurred," he said.

Jay Pasachoff, an astronomy professor at Williams College, said that Pluto's global warming was "likely not connected with that of the Earth.

man that pasachoff is one bright rocket scientist isn't he.. :?
 
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