NASA corrected temperature -- Revisited.

[Buzz Clik]

In a previous thread ( http://www.democraticunderground.com/discuss/duboard.php?az=view_all&address=115x108708 ), we were told that the upshot of the corrected temperatures was not much -- and it came in this article: http://www.realclimate.org/index.php/archives/2007/08/1934-and-all-that/

The discussions were illuminating, but it was still difficult to visualize the impact of the corrections. Gratefully, RealClimate provided the raw data which enabled me to plot the old data, the new data, and the net difference. Compare the old (uncorrected) data and the new (corrected) data:



Seriously, these data look identical. To put the changes under the spotlight, I calculated and plotted the changes in annual mean temps and 5-year averages:



Ok, now it's clear. Up until essentially 2000, the impact was nothing, and that includes the much talked about 1998 data. The post-2000 definitely has been visibly impacted. It's not the "Oh! My! God!" changes we've been led to believe, but the differences are more than trivial.

At least they've been corrected.