No, all that the researchers have done is show a change.
They haven't shown that the change was EITHER natural or manmade.
Thus, the entire premise of the article is unfounded.
Posted on 01/06/2003 10:48:27 AM PST by cogitator
Scientists discover global warming linked to increase in tropopause height over past two decades
LIVERMORE, Calif. -- Researchers at the Lawrence Livermore National Laboratory have discovered another fingerprint of human effects on global climate.
Recent research has shown that increases in the height of the tropopause over the past two decades are directly linked to ozone depletion and increased greenhouse gases.
The tropopause is the transition zone between the lowest layer of the atmosphere -- the turbulently-mixed troposphere -- and the more stable stratosphere. The tropopause lies roughly 10 miles above the Earth's surface at the equator and five miles above the poles. To date, no scientist has examined whether observed changes in tropopause height are in accord with projections from climate model greenhouse warming experiments.
The comparison was made by Livermore scientists Benjamin Santer, James Boyle, Krishna AchutaRao, Charles Doutriaux and Karl Taylor, along with researchers from the National Center for Atmospheric Research, NASA Goddard Institute for Space Studies, the Max-Planck Institute for Meteorology and the Institut for Physik der Atmosphere in Germany. Their findings are reported in the today's (Jan. 3) online edition of the Journal of Geophysical Research-Atmospheres.
This research undercuts claims by greenhouse skeptics that no warming has occurred during the last two decades. Such claims are based on satellite measurements of temperatures in the troposphere, which show little or no warming since the beginning of the satellite record in 1979.
"Weather balloons and weather forecast models show that there's been a pronounced increase in the height of the global tropopause over the last two decades," Santer said. "Our best understanding is that this increase is due to two factors: warming of troposphere, which is caused by increasing greenhouse gases, and cooling of the stratosphere, which is mainly caused by depletion of stratospheric ozone. Tropopause height changes give us independent evidence of the reality of recent warming of the troposphere."
The Livermore research supports the bottom-line conclusion of the 2001 Intergovernmental Panel on Climate Change (IPCC), which states that, "most of the observed warming over the last 50 years is likely to have been due to the increase in greenhouse gas concentrations."
Earlier research showed that changes in the Earth's surface temperature, ocean heat content, and Northern Hemisphere sea ice cover are other indicators of human effects on climate change.
"The climate system is telling us a consistent story -- that humans have had a significant effect on it," Santer said. "We're seeing detailed correspondence between computer climate models and observations, and this correspondence is in a number of different climate variables. Tropopause height is the latest piece of the climate-change puzzle."
To support the research, Livermore scientists examined tropopause height changes in climate-change experiments using two different computer climate models. Both models showed similar decadal-scale increases in the tropopause height in response to changes in human-caused climate forcings. The patterns of tropopause height change were similar in models and so-called 'reanalysis' products (a combination of actual observations and results from a weather forecast model).
The model experiments focused on both manmade climate forcings, such as changes in well-mixed greenhouse gases, stratospheric and tropospheric ozone, and on natural forcings, such as changes in volcanic aerosols. The forces have varying effects on atmospheric temperature, that in turn affect tropopause height, the report concludes.
Founded in 1952, Lawrence Livermore National Laboratory is a national security laboratory, with a mission to ensure national security and apply science and technology to the important issues of our time. Lawrence Livermore National Laboratory is managed by the University of California for the U.S. Department of Energy's National Nuclear Security Administration.
Sign me Up!
Try selling "Global Warming" worries to folks in Northern Ohio!
This research undercuts claims by greenhouse skeptics that no warming has occurred during the last two decades. Such claims are based on satellite measurements of temperatures in the troposphere, which show little or no warming since the beginning of the satellite record in 1979.
I can only think that if the troposphere is thicker (and therefore has more mass?), and its average temperature is unchanged, then its total heat content must have increased.
My wife has this.
But, so what? The box just got bigger. This doesn't show that the rate of heat input increased.
Now if the altitude of the Tropopause has increased, does that not imply lower average temperatures below the Tropopause?
This research undercuts claims by greenhouse skeptics that no warming has occurred during the last two decades. Such claims are based on satellite measurements of temperatures in the troposphere, which show little or no warming since the beginning of the satellite record in 1979.
"Weather balloons and weather forecast models show that there's been a pronounced increase in the height of the global tropopause over the last two decades," Santer said. "Our best understanding is that this increase is due to two factors: warming of troposphere, which is caused by increasing greenhouse gases, ...
Now if the altitude of the Tropopause has increased, does that not imply lower average temperatures below the Tropopause?
Ouch. That makes my head hurt trying to figure this mess out. Why can't we just say, "changes in the earth's climate are likely caused by the sun," and leave it at that?
No, all that the researchers have done is show a change.
They haven't shown that the change was EITHER natural or manmade.
Thus, the entire premise of the article is unfounded.
It was 0.6 C over the whole 20th Century. In the past 25 years or so, global temperatures have increased about 0.4 C, (or 1.8 C century). Those two observations aren't in conflict because there was a slight drop in global temperatures from the 1940s to the 1970s.
I think it implies that temperatures below the tropopause have increased.
Sorry to hear that. She must be an airhead.
Global cooling may be harmful to your health if you are homeless or impoverished. Freezing temperatures have been known to cause physical injury and death, especially among disadvantaged people.
If you learn that your frostbite is due to cooling actions instigated by environmentalists, consult your local lawyer. He or she can advise you of your chances of winning a lawsuit against the "Gotta be cool" crowd.
It would make sense to observe an increase in troposheric temperature followed by an increase in height/mass and say that the latter was a reaction to the former. However, there is quite definitely no such observation.
Which led to a number of books published about the coming ice age. The more recent rise in temperature has led to many books published about global warming.
I don't know the exact statistics, but there seems to be a strong correlation.
"This research undercuts claims by greenhouse skeptics that no warming has occurred during the last two decades. Such claims are based on satellite measurements of temperatures in the troposphere, which show little or no warming since the beginning of the satellite record in 1979.
"Weather balloons and weather forecast models show that there's been a pronounced increase in the height of the global tropopause over the last two decades," Santer said. "Our best understanding is that this increase is due to two factors: warming of troposphere, which is caused by increasing greenhouse gases, and cooling of the stratosphere, which is mainly caused by depletion of stratospheric ozone. Tropopause height changes give us independent evidence of the reality of recent warming of the troposphere."
The first paragraph says "there is no evidence of warming in the troposphere". The second says that the increased size in the tropopause is due to two factors, one of which is "warming of troposphere".
Do you see what kind of crap this article is? If there is no evidence that there is warming of the troposphere then how can you say that the warming of the troposphere causes the increase in size of the tropopause?
If anything, this same evidence - no warming of the troposphere - disproves the hypothesis.
As near as I can tell from this almost unintelligible summary, this is just another computer-model masturbation by some guys with too much beer and not enough grant money.
"..seems like..." is not the correct operative word. We KNOW that the last time the planet was warmer than it is now, it was a period of great beneficence to most kinds of life (especially human). The "Medieval Optimum" period WITHIN RECORDED HISTORY was warmer than now, and the historical and archealogical record all indicate that it was a "boom" period for humanity.
The "global warmers" are just looking for another lever to overturn our liberties and institute more CONTROLS over our lives.
Explains those hot and cold spells.
"Recent research has shown that increases in the height of the tropopause over the past two decades are directly linked to ozone depletion and increased greenhouse gases."
The research says nothing of the sort. They use false information (that there is warming in the troposphere which even the article states is false) and make an unjustified assumption (that man-made activitis caused both the warming of the troposphere (which is false)and the increase in size of the tropopause (which is unknown)) to fit a pre-conceived idea that some political document that has been said to be false by even some of the author's of it is true.
GIGO!
If there was no warming of the troposphere, there would be no change in the height of the tropopause. Analyses of Microwave Sounding Unit (MSU) data to derive tropospheric temperatures have heretofore not shown an increasing tropospheric temperature trend. However, that picture is changing, according to abstracts of papers from two different groups that will be presented at the February American Meteorological Society meeting. These analyses, which include one by the Marshall Space Flight Center/University of Huntsville group that performed prior widely-quoted MSU tropospheric temperature analyses, DO show a warming of the troposphere. The increase in tropopause height is consistent with these analyses.
The implication that the authors of the study under discussion may have wished to avoid was that the prior analyses of tropospheric temperature were in error. I guess he'll wait for the researchers themselves to provide the update at the AMS meeting in February.
If the temperature rise in the next century doesn't exceed 2 C globally, the effects are likely to remain minimal, but they will be noticeable. In a second reply to you I will direct you to a thread where I expand on this topic.
Short answer: 330-520 meters at all stations.
Yeah--that's the ticket! It's...it's tropopause height, not temperature, that is a measure of "global warming!"
Where have I heard that before?
If the &$!@&$# planet froze over, they'd find a correlation between the length of porcupine quills and "global warming."
That's the ticket!
--Boris
The fact that we are at Solar Maximum has NOTHING to do with it.
Man has MUCH more affect on the earth than does - you know - the zillion-gigawatt fluctuations in the sun's output.
If you drive an evil SUV, it should be impounded, and YOU should be thrown into prison.
(Please, don't anybody ask me for links to solar-output / sunspot-flare activity data - I'm very busy, I don't have the time)
There are also some 'experts' who say that since the sun has already burned off more than half its 'estimated' original hydrogen content, it may go nova at any moment - thereby obliterating everything for 42 quadrillion miles in every direction.
Fine. Whatever. I have work to do.
All right who raised the tropopause and didn't put it back down when they were done?
So how does helping to provide evidence that blames United States SUV owners for causing global warming actualy help to 'ensure national security' ? And why on earth are they grasping at straws to help prove that ? They used 'computer models' to implicate human causation. As others have pointed out we still have no scientific factual evidence that explains the changing height that was reportedly measured. Human action is being indirectly implicated through a 'computer model'. Someone needs to explain to these boneheads that human designed computer models can never be considered unbiased when utilized to address human related issues. They can only provide probablities. Not solid evidence. Nor implied evidence. Models and predictions from computers are not scientific fact.
An intellectually honest answer would say just what this article says: Evidence to this point shows no warming of the troposphere.
Anything more than that is not justified at this point.
I find it fascinating that true believers of the global-warming religion go to such lengths to ignore real evidence in favor of computer projections and other estimates that have no basis in reality and are changed every few years when the data disprove them.
These terms are pretty well defined by now.
"troposphere: 1. The lower layers of atmosphere, in which the change of temperature with height is relatively large. It is the region where clouds form, convection is active, and mixing is continuous and more or less complete. [JP1] 2. The layer of the Earth's atmosphere, between the surface and the stratosphere, in which temperature decreases with altitude and which contains approximately 80% of the total air mass. (188) Note: The thickness of the troposphere varies with season and latitude. It is usually 16 km to 18 km thick over tropical regions, and less than 10 km thick over the poles."
I couldn't find an equivalently detailed definition for stratosphere, but one way to define it is the area of the atmosphere where the temperature increases with altitude, rather than decreases.
The abstracts for these papers are already available online; I can provide URLs to the papers if you want them. These papers include figures of data that has already been acquired and analyzed. Such is the pace of scientific advance these days. If people cling to outdated arguments, then they will be left behind.
An intellectually honest answer would say just what this article says: Evidence to this point shows no warming of the troposphere.
An accurate answer would say: previous analyses of the data show no warming of the troposphere; current analyses of the data now show warming of the troposphere.
I find it fascinating that true believers of the global-warming religion go to such lengths to ignore real evidence in favor of computer projections and other estimates that have no basis in reality and are changed every few years when the data disprove them.
The real evidence is the observed increase in the height of the tropopause. There are only a few explanations for that observation that make sense.
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