How Well Do Reanalyses Capture the Lower Stratosphere Temperature Hiatus from 1994 to Present?

The globally averaged temperature of the lower stratosphere (TLS) as observed by satellites having the MSU channel 4 and AMSU channel 9 has been relatively flat since the thermal impacts of Mt Pinatubo were reduced in 1994. This flat trend or ‘hiatus’ has been shown to be a cancelation of the warming effects due to increasing ozone amounts and the cooling effects due to increasing greenhouse gases in the lower stratosphere. Users of reanalysis data need to know how well the TLS layer is observed by the more recent reanalyses. The TLS layer is interesting in that it is comprised of the upper troposphere and lower stratosphere in the tropics, and is entirely comprised of the lower stratosphere in the mid and high latitudes. 2016 was an interesting year in that there was tropical cooling in the lower stratosphere due to persistent Quasi-Biennial Oscillation westerlies and tropical warming in the upper troposphere due to the strong El Nino. The four most recent reanalyses (CFSR, MERRA-2, ERA-Interim, and JRA-55) will be compared to see how well they capture the TLS layer and how these competing atmospheric phenomena impact this layer.