a historical approach

The website: http://www.aip.org/history/climate/co2.htm uses a historical approach to define the events that lead the vast majority of scientists to understand that indeed humans can greatly affect both their local and global environments. It begins with an anecdotal story in which Tyndall hypothesizes about the global ice ages by observation of the landscape. They then go on to concede that the data available at the time was insufficient but the physics suggested that some process had to be occurring in order for the known physics to match observation. It then shows that Tyndall calculates the heat trapping capacity of water vapor and CO2. While working on their theories they come across more and more evidence of how burning coal could lead to a rise in temperature. It is noted that these were always footnotes or speculations in working with the basic science of CO2 infrared absorption. It goes on to show that as technology progresses we then are able to use spectrographic data, but due to the lack of precision of the instruments, they were not able to concretely demonstrate a specific trend. It wasn't until a dynamic layered model of the upper atmosphere was envisioned that scientists could relate all the observations into a theory. It goes on to mention that by the 1930's one naval researcher had developed a decent theory, but was so obscure that his work was not widely read. It goes on to talk about the lack of evidence for global warming at the time until the second world war and the the advent of computers to be able to calculate the intricate effects of the H2O/CO2 layering that work together to create the greenhouse effect. At this time researchers used radiometric analysis to determine that the carbon in the atmosphere was indeed the fossil fuels that were being emitted by human industry. Until the 70's researchers were not as interdisciplinary and so were missing key components of the puzzle. With more crossover between disciplines and the Vostok ice-core samples they clearly showed an increase and that there is a lag time between introduction of CO2 and heat increase. And by 2005 the evidence was unmistakable that humans do indeed impact global climate.

This argument is very well laid out and the hyperlinks leading to more information are well suited for anyone trying to understand more about this.

Through the historical argument they show many of the stumbling blocks that scientists faced as they came to understand this phenomena, also how scientists work together and build upon ideas from their predecessors while also removing faulty ones. This shows that science is a dynamic process that changes as new information becomes available, either through new ideas/ hypotheses or by technological advancement that allows more detailed observations.

Now that science has revealed a potential problem it is up to human society to act.

I doubt that if scientists observed a large asteroid headed for earth, that there would be much denial about it or lack of political will to do something about it. But because of the complexity of the chemistry, physics and biology that are involved in understanding this issue, it makes people weary of accepting the facts, and it makes it easier to politicize this issue.