Global Warming

I've so far read this in an editorial, and on a site with a clear bone to pick against Global Warming. I'm interested to see if I can find this in an independent or hostile source, because it would be pretty noteworthy if it's true:

Data, though, is often refined and recalibrated. When NASA retooled its yearly temperature figures recently, it was discovered that 1998 wasn’t the warmest year in the millennium. That dubious title now belongs to 1934.

The year 1998 only dropped one place though. It was the second hottest year during the past century. Third place belongs to 1921

Now it appears that four of the top 10 years in temperatures were from the 1930s: 1934, 1931, 1938 and 1939. Three of the top 10 warming years were from the last 10: 1998, 2006 and 1999. But four of the past six years fell well below average in warming, ranking lower than the year 1900.