>The following two papers by Guan and Nigam are the most in depth and informative analyses of Sea Surface Temperature (SST) for the 20th Century that I’ve run across to date.
The first in chronological order is Guan and Nigam, 2008: Pacific sea surface temperatures in the twentieth century: An evolution-centric analysis of variability and trend. J. Climate, 21(12), 2790-2809:
And the second is Guan and Nigam, 2009: Analysis of Atlantic SST variability factoring inter-basin links and the secular trend: clarified structure of the Atlantic Multidecadal Oscillation. J. Climate, 22(15), 4228-4240
I am presenting them without further introduction. I am still studying both papers, and I will not be able to answer many of your questions. But I am interested in your impressions on what you believe to be the major points of the papers, so I won’t attempt to influence your conclusions by stating mine.