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Originally Posted by Cannon Shell
The earth is always in a warming or cooling trend. That is not the dispute. The dispute is the effect of man on that warming or cooling. The author of that report comes to the conclusion that based on the data presented that humans account for a minuscule amount of the factors that may cause or accelerate global warming. Perhaps IF you read that you would understand that. The question that i have is that if effect of human activity and the much used "carbon" footprint is virtually nil then why are we spending so much time, money and energy on worrying about it? Science is making new discoveries and refuting old ones all the time. There is so much data with contrary findings that i tend to believe the less radical of the two arguments. That is that global warming is overstated and largely free of human interference.
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Science isn't "... and refuting old ones all the time". Very rarely have "old discoveries" been completely refuted. Science, 99% of the time, builds and expands, rather than tears down. That's the type of assumption some might make when their science exposure is pretty much only from the evening news (which loves to try and make things black and white and extremely simplistic)
A different kind of author might draw a much different conclusion. Try this: it's a peer-reviewed well-respected consensus of the science to date. Sorta cinched the global warming-man's involvement thing. Nothing has been refuted since, only expanded upon by further information. You might have to pay to read it on-line.
Nature 408, 184-187 (9 November 2000) | doi:10.1038/35041539; Received 6 January 2000; Accepted 26 September 2000
Acceleration of global warming due to carbon-cycle feedbacks in a coupled climate model
Peter M. Cox1, Richard A. Betts1, Chris D. Jones1, Steven A. Spall1 & Ian J. Totterdell2
Hadley Centre, The Met Office, Bracknell, Berkshire RG12 2SY, UK
Southampton Oceanography Centre, European Way, Southampton SO14 3ZH, UK
Correspondence to: Peter M. Cox1 Correspondence and requests for materials should be addressed to P.M.C. (e-mail: Email:
pmcox@meto.gov.uk).
The continued increase in the atmospheric concentration of carbon dioxide due to anthropogenic emissions is predicted to lead to significant changes in climate1. About half of the current emissions are being absorbed by the ocean and by land ecosystems2, but this absorption is sensitive to climate3, 4 as well as to atmospheric carbon dioxide concentrations5, creating a feedback loop. General circulation models have generally excluded the feedback between climate and the biosphere, using static vegetation distributions and CO2 concentrations from simple carbon-cycle models that do not include climate change6. Here we present results from a fully coupled, three-dimensional carbon–climate model, indicating that carbon-cycle feedbacks could significantly accelerate climate change over the twenty-first century. We find that under a 'business as usual' scenario, the terrestrial biosphere acts as an overall carbon sink until about 2050, but turns into a source thereafter. By 2100, the ocean uptake rate of 5 Gt C yr-1 is balanced by the terrestrial carbon source, and atmospheric CO2 concentrations are 250 p.p.m.v. higher in our fully coupled simulation than in uncoupled carbon models2, resulting in a global-mean warming of 5.5 K, as compared to 4 K without the carbon-cycle feedback.