As has been noted in previous posts, Tamino has made a "bet" that global temperatures would continue to increase between now and 2015 in line with the 1975 to 2007 trend. The conditions of the bet for the year 2008 are as follows:
1. If the average global temperature anomaly, as measured by NASA GISS, equals or exceeds .7350 degrees Celsius, the "still-warming" side will receive one point.
2. If the average global temperature anomaly, as measured by NASA GISS, is less than or equal to .4035 degrees Celsius, the "not-warming" side will receive one point.
3. If the average global temperature anomaly, as measured by NASA GISS, falls between these two figures, both sides will receive zero points in 2008.
The May figures show a modest decline in the NASA GISS global temperature anomaly from April as well as a second, more modest, downward revision in March's global temperature anomaly from the previous month. There was also a .02 degree upward revision in the January 2008 anomaly. The May global anomaly was .36 degrees Celsius, .05 degrees lower than the April global anomaly of .41 degrees. The average NASA GISS global temperature anomaly thus far for the first five months of 2008 is .348 degrees Celsius. In order for the "not-warming" side to win a point in 2008, the average anomaly for the reminder of the year would need to be below .4431 degrees. My own forecast for the remainder of the year is for the global temperature anomaly to average .5113 degrees. Thus, I don't expect that the "not-warming" side will win the point in 2008. However, the threshold below which the "not warming" side would win the bet slowly creeps higher with each passing month.