An alternative perspective on 3 degrees C?
This post was originally intended as a short comment questioning certain aspects of the methodology in JC’s post of December 23, “3 degrees C?”. But every methodology is bound to have shortcomings, raising the possibility that Judith’s methodology might nevertheless be best possible, those shortcomings notwithstanding. I was finding my arguments for a better methodology getting too long for a mere comment, whence this post. (But if actual code is more to your fancy than long-winded natural language explanations, Figures 1 and 2a can be plotted with only 31 MATLAB commands .)
Judith’s starting point is “It is far simpler to bypass the attribution issues of 20th century warming, and start with an early 21st century baseline period — I suggest 2000-2014, between the two large El Nino events.” The tacit premise here would appear to be that those “attribution issues of 20th century warming” are harder to analyze than their 21st century counterparts.