Originally posted by kmax87I don't think this is correct.
All the heat that can be trapped is already done so by current levels of CO2 in the atmosphere. [b]As any increase in CO2 concentration cannot close these windows concerns that increasing CO2 levels will serve as a mechanism for global warming are unfounded.
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As I understand it, an increase in the concentration of CO2 increases the 'optical thickness' of the atmosphere (a measure of the opacity of the atmosphere to longwave radiation emitted from the ground after heating by the sun). This in turn increases the absorptivity of the atmosphere, leading to a greater temperature through more absorption of longwave radiation.
In any case you only have to look at Venus to see the effects of CO2 concentration levels on the surface temperature, though the levels on Venus are astronomically higher than on the Earth.
The key to untangling the mess of what might or might not happen is to understand all the feedbacks involved I think. You mention the negative feedback of water vapor (clear skies = more heating -> more clouds = less heating by the sun). The problem is there are SO MANY feedbacks to consider, positive and negative. How the hell are we supposed to know how they interact and which one wins? For instance increasing water vapor in the atmosphere again increases the atmosphere's optical thickness, leading to more trapping of longwave radiation from the surface and a rise in surface temperature. This rise in surface temperature increases the 'holding capacity' of the atmosphere to water vapor and the evaporation, leading to more water vapor in the air, yet more optical thickness and continuing rise in surface temperature = positive feedback. This feedback is thought to be the reason Venus is the way it is - all of its surface water evaporated and was eventually broken up by dissociation leading to an abundance of CO2 in its atmosphere - the main constituent.
More on feedbacks - the realisation that the shutting down of the Gulf Stream, from the effects of global warming (i.e. melting Greenland's ice sheet), could actually lead to much cooler weather over Europe and possibly kick start an Ice Age is relatively new (to be honest I don't think current models with their predictions of hotter surface temperatures over the next 100 years take this into account, but I'll have to check...). So this is a BIG negative feedback. Who knows which feedbacks, positive or negative, have yet to be discovered?
I recently went to a talk by George Philander - a leading scientist on El Nino dynamics - on the subject of global warming. Two things struck me about it. One was his concern about Michael Crichton's book in that how an intelligent layperson after 2 years of study could come up with such a negative view regarding the possibility of global warming - the concern being that inevitably it is the public that needs to know the truth and it is up to intelligent men such as Mr Crichton to educate them. The other is that concerning global warming, he could only say that the present was a time for 'circumspection'. In other words, no-one really knows, but we'd best all stay alert to any possibility.
Originally posted by ElleEffSeeehahaha, "well aware that extrapolating such a short trend was a mistake", try plugging in the dates 70's to 00's:
Hey I found a link that answers some of William Gray's points!
http://www.realclimate.org/index.php?p=188
"Where does the myth come from? Naturally enough, there is a kernel of truth behind it all. Firstly, there was a trend of cooling from the 40's to the 70's (although that needs to be qualified, as hemispheric or global temperature datasets were only just beginning to be assembled then). But people were well aware that extrapolating such a short trend was a mistake (Mason, 1976) . "
Originally posted by zeeblebotHere's a plot of global mean surface temperature anomaly over the last hundred and fifty years from the Met Office.
hahaha, "well aware that extrapolating such a short trend was a mistake", try plugging in the dates 70's to 00's:
"Where does the myth come from? Naturally enough, there is a kernel of truth behind it all. Firstly, there was a trend of cooling from the 40's to the 70's (although that needs to be qualified, as hemispheric or global temperature datasets w ...[text shortened]... le were well aware that extrapolating such a short trend was a mistake (Mason, 1976) . "
http://www.met-office.gov.uk/research/hadleycentre/CR_data/Annual/HadCRUG.gif
Just judging by eye you can see the overall trend over the period is upwards, with a short period drop-off around 1940-50 - the short period which Mason mentions correctly is not indicative of a longer period trend.
Originally posted by zeeblebotIt's not necessarily the case that one type of research is being funded, but more likely that most research that is being performed is giving up the same results. For example for the upcoming fourth IPCC report, meteorology centers all around the world have submitted output from their latest computer models to a big storage location, which scientists can fetch and peform research on (look up PCMDI - incidently not just anyone can access this data which answers your question about what information isn't freely available). Most models provide experiments such as runs with double CO2 concentrations to compare with the current state climate. These models always produce a higher global mean temperature (though I found out they don't include the effects of a melting Greenland leading to deflection of the Atlantic Gulf Stream as I mentioned in an earlier post - too complicated a process to model as yet). The models aren't engineered specifically to produce this rise in temperature, that's just what they show. When technology improves, effects such as this Gulf Stream deflection possibility can be added and then we'll see what answers they start to come up with.
that sort of scaremongering has been going on for awhile, at least since the seventies .... that funding has to come from somewhere. there a lot of people chasing public dollars, and they can come up with all kinds of reasons why they should be the ones to get it. so where's the counterpoint? it appears only one line of research is being funded; the one that "everyone" agrees with. how is that good?
There seems to be a conflict of interest here with regards to the supposed 'encouragement' of funding for global warming protagonists. Why would the government encourage something that acts to demonize one of its main sources of income, and one of the main drivers of its economy - oil and gas?
Originally posted by ElleEffSeeeThis point was undescored in the Greenhouse Conspiracy. The sense that of the thousands of variables that influence the weather only a few 'important' ones are chosen to run the computer models. It becomes a question that if we are not even sure of the full extent or scope of each feedback mechanism let alone of their coupled interaction then we arrive at conclusions that are at best fundamnetally flawed.
The key to untangling the mess of what might or might not happen is to understand all the [b]feedbacks involved I think. You mention the negative feedback of water vapor (clear skies = more heating -> more clouds = less heating by the sun). The problem is there are SO MANY feedbacks to consider, positive and negative. How the hell are we supposed to know how they interact and which one wins? [/b]
For example the period that followed the second world war ( the fifties particularly if I remember the article correctly) was unusually cool in terms of the temperature record.
By the logic of industrial activity and increased production of greehouse gases that period should have experienced a steady increase in temp but the temperature record goes against the expected correlated industrial activity trend.
The argument that all of acedemic investigation on climate change is funded for those wanting to do research to show global warming may be a baseless assertion, an unfounded perception, but it would seem that the models can say what you want them to say. The IPCC data for Kyoto show upper an lower trends yet it seems the upper trends get more press.
The sacrifices that 'must' be made as part of the process of ratifying the protocols mean that poorer countries that have only now gotten onto the industrial treadmill are further disadvantaged and villified because they cannot jump to the current state of the art in industrial process, but instead are grappling with technologies long junked by the west. It becomes a further example of global arrogance that only when the west has given up a profitable practice will it ever be deemed unacceptable. or carbon trading that does npot even attempt to reduce the net production of excess carbon on the planet but seeks to cleverly redistribute its point of ventilation.