A grown-up response to climate change

By Ian Douglas Science Last updated: September 14th, 2009

It is very likely that the global mean temperature will rise by at least two degrees by the end of the century, and continue to rise after that. Historical rises have corresponded with increases in concentration of carbon dioxide in the atmosphere, and the burning of fossil fuels is the source of this increased concentration.

A changing climate addressed
Not so complicated, is it. It is true that there have been natural climate changes in the past, but this isn’t one of them. Nor is it harmless, or simply a way to enjoy some nicer weather in summer, or take the edge off winter chills.
The Royal Society has been looking at methods of negating the effects of increased levels of carbon dioxide in the atmosphere, and have published their findings in a paper that makes recommendations on emissions, but concentrates on the possibilities of bioengineering to trap the CO2 and reduce the effect of solar radiation on average temperatures.
Carbon dioxide removal techniques discussed include afforestation (cheap, but of limited use for carbon removal), bioenergy and carbon sinks on land, burial of carbon-trapping biomass such as wood on land and in the ocean to trap the carbon dioxide that would otherwise be released in decomposition or burning, enhanced weathering of rocks (very effective but expensive) and ocean fertilisation.
Solar radiation management techniques tend to seem a little more far-fetched, involving as they might increasing the reflectivity of large parts of the earth’s surface or the clouds or space-based reflector systems, but they’re seriously discussed. Their costs and feasability (generally prohibitive) and effectiveness (low to poor) are laid out for use in a sensible informed dicsussion.
Effectiveness and affordability are compared in text and graphical formats, and a framework for governance of any schemes, which would have to be huge in their scope, is laid out.
A good, science-based statement of the possibilities of working to limit climate change is a welcome addition to the debate.
The decision to take the climate science for granted in this report might attract some criticism from followers of Ian Plimer, author of the milion-selling but ludicrous Heaven and Earth, bible of the denial camp. Fortunately for the authors of the report Mr Plimer is entirely mistaken in his views, from his belief in an entirely fictional period of cooling after the second world war to the idea that the sun is mostly made of iron rather than hydrogen and helium and that this, through the device of solar flares, has some cyclical effect on temperatures on earth, so they need not distract us any further.