In contradiction to perceived wisdom, the airborne fraction of carbon dioxide hasn't increased during the last five decades, or, indeed, for the last 150 years, claims new research
The findings suggest that estimates of mankind's impact on the environment are more than 80 percent higher than they should be.
To assess whether atmospheric CO2 levels are increasing, Wolfgang Knorr of the Department of Earth Sciences at the University of Bristol has re-analyzed available atmospheric carbon dioxide and emissions data since 1850, reports Science Daily.
Says Knorr: "Several recent studies have highlighted the possibility that the oceans and terrestrial ecosystems have started loosing part of their ability to sequester a large proportion of the anthropogenic CO2 emissions. This is an important claim, because so far only about 40 percent of those emissions have stayed in the atmosphere, which has prevented additional climate change.
"[My] study re-examines the available atmospheric CO2 and emissions data including their uncertainties. It is shown that with those uncertainties, the trend in the airborne fraction since 1850 has been 0.7 ± 1.4 percent per decade, i.e. close to and not significantly different from zero.
"The analysis further shows that the statistical model of a constant airborne fraction agrees best with the available data if emissions from land use change are scaled down to 82 percent or less of their original estimates. Despite the predictions of coupled climate-carbon cycle models, no trend in the airborne fraction can be found. "
Climate computer models also assume that the airborne CO2 fraction will increase. Knorr's findings seem to suggest that the warmist's claims of an approaching climate Armageddon are somewhat overstated.