Riding in a taxi through south Belfast yesterday, it was a warm spring day. “Seventeen degrees”, observed the cabbie, “that’s not natural in February”. Climate change is something that hits you in the face when you step out the door; it means walking to the station on 8th February in an open-necked cotton shirt and sports jacket and not worrying that a coat might have been advisable. But is it all so straightforward?
The Journal of Glaciology is probably not the highest selling magazine. Were it not for yesterday’s Irish Times weather page, a report on the causes of the collapse of the Larsen B ice shelf in Antarctica in 2002 would have passed without notice amongst most people in Ireland.
The demise of the ice shelf has been cited as a significant indicator of climate change, and so it appears to be; but the story is not as simple as the exhaust fumes from my old Nissan causing carbon dioxide in the atmosphere, which is increasing the temperature and melting the ice. The Irish Times piece was also covered by BBC Wales who reported a new study from scientists from the University of Aberystwyth and Colorado University:
Prof Glasser said the dramatic event was “not as simple as we first thought”.
He acknowledged that global warming had a major part to play in the collapse, but emphasised that it was only one of a number of contributory factors.
“Because large amounts of meltwater appeared on the ice shelf just before it collapsed, we had always assumed that air temperature increases were to blame,” he added.
“But our new study shows that ice-shelf break up is not controlled simply by climate.
“A number of other atmospheric, oceanic and glaciological factors are involved.
“For example, the location and spacing of fractures on the ice shelf such as crevasses and rifts are very important too because they determine how strong or weak the ice shelf is.”
Dr Scambos, of the University of Colorado’s national snow and ice data centre, said the ice shelf had probably been in distress for decades before its demise.
“It’s likely that melting from higher ocean temperatures, or even a gradual decline in the ice mass of the peninsula over the centuries, was pushing the Larsen to the brink,” he added.
Climate change may be a much longer process than is accounted for by simple post-war industrialisation. If there is a centuries long shift that has been exacerbated by the huge increase in carbon emissions, what Plan B is there? What measures are proposed if carbon emissions are reduced, but the reduction does not halt the increase? Who is planning for the shift of the population of Bangladesh or the resettlement of the peoples of drought-stricken sub-Saharan Africa?