New Scientist: Yes, but it shouldn't. Undoubtedly, the sceptics will latch on to the many admissions of uncertainty in the report. They will certainly note its acceptance that some regions of the world were as warm as they were during the Medieval Climate Anomaly when Europe basked in balmy temperatures between AD 950 and 1250 thanks to natural variation as in the late 20th century. This has long been a favourite topic among deniers who argue that if a natural mechanism was responsible for raising temperatures...