The Divergence between Surface and Lower Troposphere Global Temperature Datasets and its Implications

I include a graph in my monthly global surface temperature and lower troposphere temperature anomaly updates that compares the average of the global surface land+ocean temperature anomaly products (from GISS, NCEI and UKMO) to the average of the global lower troposphere temperature anomaly products (from RSS and UAH).  (See Figure 9 from the most recent August update for an example.) Because all of the suppliers use difference base years for their anomalies, I’ve recalculated the anomalies for all using the WMO-preferred reference period of 1981-2010.

Figure 1

My Figure 1 is similar to Figure 9 from those updates, but in it, I’ve also shown the linear trends for the global surface and lower troposphere temperature anomaly products.  The linear trend, the warming rate, presented by the average surface-based products is noticeably higher than the average lower troposphere products.   This, of course, according to Dr. Gavin Schmidt (head of NASA GISS)…