While this is greater than the threshold I gave a few weeks ago, where there would be no cherry picked starting point that would give a negative slope to the present, there were sufficient adjustments on the cool side to prevent that from happening.
In the coming days there will be some adjustments to the data before the latest 13 months that Roy Spencer gives on his post, but for now there is one and only one month which, if chosen as the starting point, gives a negative linear slope to January 2016: December 1997 (18.1 years ago), for which the slope is
-0.000002°C/decade
and the R2 is a whopping 4.0e-11.UAH made more adjustments to their version 6.0beta4. It's a good example of the complexity of their model, and of the open parameters they have to play with. Roy Spencer writes:
We determined this is most likely due to a residual mismatch between the MSU channel 2 weighting function altitude on the early satellites versus the AMSU channel 5 weighting function altitude on the later satellites. We already knew AMSU5 peaks lower than MSU2, and had chosen Earth incidence angles in each to get a match based upon theory. But apparently the theory has some error, which we find equates to about 150 meters in altitude. This was enough to cause the issues we see….land too warm at low elevations, too cold for elevated ice surfaces.
We therefore changed the AMSU5 reference Earth incidence angle (from 35.0 to 38.3 deg.) so that the trends over Greenland and the Himalayas were in much better agreement with the surrounding areas. We also find that the resulting LT trends over the U.S. and Australia are in better agreement with other sources of data.
The net result is to generally cool the land trends and warm the ocean trends. The global trends have almost no change from beta4; the change mostly affects how the average trend in 2.5 deg. latitude bands is ‘apportioned’ between land and ocean.
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