You report (Arctic ice melt likely to break record as 100,000 sq km disappears per day, 24 August) that research just published in Nature says that warming in the Antarctic "where temperatures have risen about 1.5C over the past 50 years" is unusual but not unprecedented. That gives the impression that typical temperatures in Antarctica have risen by about 1.5C. In fact, there was no statistically significant increase in average Antarctica temperatures over the 50 years to 2006. (The relevant study, of which I was a co-author, was published in Journal of Climate last year.)
The latest Nature research refers to warming at a location in the Antarctic peninsula. While the peninsula has certainly warmed rapidly over the last 50 years – our paper estimated by slightly more than 1.5C – it represents only a small part of Antarctica by area and even less by ice sheet volume, and its climate is distinct from that of continental Antarctica.
Nicholas Lewis
Bath, Somerset