Analyzing gas bubbles inside ice cores drilled in deep Antartic ice, we know that the pre-industrial concentration of CO2 (prior to 1750 AD) was 280 ppm. 2007 readings showed that it had risen to 383 ppm. More than 70% of the increase in greenhouse gases (GHG), came about after 1970. At the latest readings taken last April by Hawaii’s Mauna Lau Observatory, it stood at 396.18 ppm. “This worldwide rise in CO2 concentration stems mainly from the planet’s use of fossil fuels” (Source IPCC, p.37).
The US-Russian-French research station located in Vostok, in Eastern Antarctica, is researching the deepest ice cores, which have been used to reconstruct the latest 400,000 years of development: the current situation bears no resemblance at all to that particular period. The scientific community is looking into the possible causes of global warming or cooling of the planet, both natural and man-made: the anthropogenic (man-made) causes which are contributing to global warming are the rise in GHGs, or the tropospheric ozone; but scientists have also conducted research into the cooling effect of other man-made factors such aerosol sprays and increased surface albedo stemming from changes in land usage. Similarly, solar variation as an important natural factor contributing to global warming, and volcanic eruptions as a natural contributing factor to cooling, are also the subject of ongoing research.
By reviewing and analyzing the results of the studies that have been conducted so far, the latest IPCC Report (2007) stated with a certain degree of accuracy for the first time ever (it was not so clear in previous Reports) that the main cause of global warming are anthropogenic in origin GHGs.
This analysis should dispel the existing doubts that appear regularly concerning climate change as an unequivocal phenomenon on which man-made activity has an unquestionable effect. Scientific knowledge continues to advance and it is quite likely that in the next few years the complex simulation models will have developed considerably and will allow us to understand the variables that determine the speed at which the process is evolving.
Meanwhile, a part of the debate focuses on deciding whether or not it is really worth making climate change a transversal constraint on many policies, with the subsequent economic impact that this entails. I recommend you take a look at a selection of videos that, combining a keen sense of humor and indisputable knowledge, deal with the negation of scientific evidence on climate change, and maybe even shed some light on the political attitude of delaying measures for mitigating climate change. I’ll be sharing with you six more major truths about climate change in the next weeks.