The skeptics will make a meal of this when it comes out, but if they did their job properly (I know this is impossible!) they would have found it. It relates to a problem with SST data in the late 1940s. The problem will get corrected for at some point. SSTs need adjusting as there must be from buckets for the period from Aug45 by about 0.3 gradually reducing to a zero adjustment by about the mid-1960s. The assumption was that after WW2 they were all intake measurements and didn't need adjusting. This will reduce the 1940-1970 cooling in NH temps. Explaining the cooling with sulphates won't be quite as necessary.