Originally Posted by Dreamworld
The fundamental of your argument, C02 and gases are responsible for the Globe Warming, and higher temperatures is fallacious. In that pretty chart Al Gore showed us, there is a 100 year separation in between temperature and C02 levels, and it showed C02 came in affect 100 years after temperature. Destroying the whole fundamental aspect of that side of the argument. Tempature cause C02 levels not the other way around.
Explain this please.
Thank you for the opportunity, I would be happy to. Actually, I linked this and quoted it extensively already, but I understand it was probably easy to miss with the low signal-to-noise ratio in this thread.
Here is a solid link for you :
http://www.realclimate.org/index.php...-temp-and-co2/
This was written in 2007 by Eric Steig, an isotope geochemist at the University of Washington in Seattle. His primary areas of research include core records, geological history of ice sheets, ice sheet dynamics, statistical climate analysis, and atmospheric chemistry. He is an editor of the journal Quaternary Research and has published more than 60 peer-reviewed articles in international journals.
Sections pertinent to your question:
What is being talked about here is influence of the seasonal radiative forcing change from the earth's wobble around the sun (the well established Milankovitch theory of ice ages), combined with the positive feedback of ice sheet albedo (less ice = less reflection of sunlight = warmer temperatures) and greenhouse gas concentrations (higher temperatures lead to more CO2 leads to warmer temperatures). Thus, both CO2 and ice volume should lag temperature somewhat, depending on the characteristic response times of these different components of the climate system. Ice volume should lag temperature by about 10,000 years, due to the relatively long time period required to grow or shrink ice sheets. CO2 might well be expected to lag temperature by about 1000 years, which is the timescale we expect from changes in ocean circulation and the strength of the "carbon pump" (i.e. marine biological photosynthesis) that transfers carbon from the atmosphere to the deep ocean.
But the calculations can only be done well when the temperature change is large, notably at glacial terminations (the gradual change from cold glacial climate to warm interglacial climate). Importantly, it takes more than 5000 years for this change to occur, of which the lag is only a small fraction (indeed, one recently submitted paper I'm aware of suggests that the lag is even less than 200 years). So it is not as if the temperature increase has already ended when CO2 starts to rise. Rather, they go very much hand in hand, with the temperature continuing to rise as the the CO2 goes up. In other words, CO2 acts as an amplifier, just as Lorius, Hansen and colleagues suggested.
In summary, the ice core data in no way contradict our understanding of the relationship between CO2 and temperature, and there is nothing fundamentally wrong with what Gore says in the film. Indeed, Gore could have used the ice core data to make an additional and stronger point, which is that these data provide a nice independent test of climate sensitivity, which gives a result in excellent agreement with results from models.
Additional link: http://www.realclimate.org/index.php...2-in-ice-cores
Where we hear it in another form (from 2004):
The reason has to do with the fact that the warmings take about 5000 years to be complete. The lag is only 800 years. All that the lag shows is that CO2 did not cause the first 800 years of warming, out of the 5000 year trend. The other 4200 years of warming could in fact have been caused by CO2, as far as we can tell from this ice core data.
The 4200 years of warming make up about 5/6 of the total warming. So CO2 could have caused the last 5/6 of the warming, but could not have caused the first 1/6 of the warming.
From studying all the available data (not just ice cores), the probable sequence of events at a termination goes something like this. Some (currently unknown) process causes Antarctica and the surrounding ocean to warm. This process also causes CO2 to start rising, about 800 years later. Then CO2 further warms the whole planet, because of its heat-trapping properties. This leads to even further CO2 release. So CO2 during ice ages should be thought of as a "feedback", much like the feedback that results from putting a microphone too near to a loudspeaker.
Please tell me if you need more on this subject. Happy to oblige.
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