exploring a frozen lake in the icy wilderness of Northern Siberia. In one spot on the lake, they cleared some of the overlying snow, and peered down at the transparent ice below. In it, they saw a myriad of trapped bubbles. After cutting into the ice, they held a flame over the hole they had created. What happened next must surely count as one of nature’s stranger phenomena: A truly huge tongue of fire suddenly erupted from this frozen pit. And the reason for this was that the bubbles were, in fact, trapped methane, slowly being released with the defrosting of the Siberian Tundra. Methane, of course, is a very potent greenhouse gas, contributing towards global warming. It is 21 times more effective in trapping heat in the atmosphere than carbon dioxide, which it does by absorbing infrared radiation that would otherwise leak away into space. Although it is found in natural gas and is biologically produced within anaerobic environments, over the last few centuries it has increasingly derived from all sorts of human activities; from farming to the production of motor cars. According to the Intergovernmental Panel on Climate Change (IPCC), the concentration of methane in the atmosphere has risen 150% globally since 1750 (although this rise appears to have tailed off recently). What is worrying, indeed frightening, about this high concentration of methane is not just the greenhouse effect it exerts per se, but the fact that in concert with a host of other global warming factors, it may help to bring about a ‘runaway effect’, leading to hugely devastating and possibly irreversible changes in the planet’s ecosphere, with each of these factors augmenting, and in turn being augmented by, all of the other factors via the contribution they make to
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