minarchist wrote on Sep 17^th, 2018 at 2:33pm:



So why do they adjust upwards for UHI?  Surely UHI should be downward adjusted?

minarchist wrote on Sep 17^th, 2018 at 2:33pm:



So what should be the amount of anomaly assessed by NOAA? To 1/100's of a degree  or use GISS estimations when the raw data for the estimation given by Gavin Schmidt gives +/- 0.5C?

"But think about what happens when we try and estimate the absolute global mean temperature for, say, 2016. The climatology for 1981-2010 is 287.4±0.5K, and the anomaly for 2016 is (from GISTEMP w.r.t. that baseline) 0.56±0.05ºC. So our estimate for the absolute value is (using the first rule shown above) is 287.96±0.502K, and then using the second, that reduces to 288.0±0.5K. The same approach for 2015 gives 287.8±0.5K, and for 2014 it is 287.7±0.5K. All of which appear to be the same within the uncertainty. Thus we lose the ability to judge which year was the warmest if we only look at the absolute numbers."

http://www.realclimate.org/index.php/archives/2017/08/observations-reanalyses-an...

And even then see how Schmidt finds an anomaly to 3 decimal places.  Accuracy vs Precision? On an estimate?

How do they know how much to adjust previous data for UHI?