Given that only half of global warming is due to CO2, while another half is caused mainly by methane, world-leading scientists such as Professor of Global Environmental Health Kirk Smith and NASA’s Prof. James Hansen call for methane reduction strategies, for instance through reducing livestock, to be implemented rather than risky and untried geoengineering carbon sequestration strategies.
Dr Smith writes:
“One tonne of methane is responsible for nearly 100 times more warming over the first five years of its lifetime in the atmosphere than a tonne of CO2. Methane is removed from the atmosphere much more rapidly than CO2, with a half-life of 8.5 years compared with many decades for CO2.”
According to NASA article entitled “Global warming in the twenty-first century: An alternative scenario“, co-authored by Professor Hansen:
“Rapid warming in recent decades has been driven mainly by non-CO2 greenhouse gases (GHGs), such as chlorofluorocarbons (CFCs), Methane (CH4), and Nitrous Oxide (N2O), not by the products of fossil fuel burning. If sources of Methane and Ozone (O3) precursors were reduced in the future, the change in climate forcing by non-CO2 GHGs in the next 50 years could be near zero.”
Source: Global warming in the twenty-first century: An alternative scenario NASA site – abbreviated version – Proceedings of the National Academy of Sciences (PNAS) – full article
Date: 2001
Source: Methane controls before risky geoengineering, please – Dr Kirk Smith New Scientist Magazine – article preview – GoodPlanet.info – full article
Date: 25 June 2009


