“Wasn’t that completely debunked when some “global warming deniers” reverse engineered Hansen’s formulas (after he refused to release them publicly) and found that they had a major bias for increasing temperatures.”
I think people are confusing US temps and global temps.
Globally, the warmest year on record was 1998.
For the US, the 1998 numbers and 1934 numbers are very close. Hansen did some data re-manipulation to make recent years beat out the 1930s warm years. The climate audit crowd, ie McIntyre, caught Hansen’s abuse of statistics, as a “Y2K bug” (but it was really a switch in data sources that biased recent temps higher, so human error/fraud not computer error. Hansen’s data ‘fixes’/errors did also impact global temp trends but do not change the fact that the warmest year on record globally was 1998.
Details on the NASA/GISS errors and corrections here:
http://answers.yahoo.com/question/index?qid=20070810111416AAttodt
http://blog.wired.com/wiredscience/2007/08/did-nasa-cover-.html
http://www.freerepublic.com/focus/f-news/1878355/posts
http://lots-o-thoughts.blogspot.com/2007/08/nasa-1934-1998-etc.html
Perhaps. But the United States temperatures are, by far, the most reliable.
Quality control and economic stability issues have led to some very poor ground-based temperature recording in Russia, many African nations and South America.
Trends in United States temperatures should not be discounted.