1990s the warmest decade for 2000 years

In a future issue of Geophysical Research Letters Michael Mann of University of Virginia report on temperature records from 13 regions in the world that cover two millennia. The records show that the 1990s appear to be the warmest decade in the norther hemisphere, and it strongly suggest that the same applies for the sourthern hemisphere. Mann and other leading British and American palaeoclimatologists conclusion is that the warming in the late 20th century has been worldwide. Mann says: “It becomes increasingly less plausible that natural variability can explain the late-20th-century warming”.