April global surface TempLS down 0.15°C from March.

The TempLS mesh anomaly (1961-90 base) was 0.693°C in April, down from 0.843°C in March. That brings it back to the level of February, undoing the sudden rise to March. The NCEP/NCAR reanalysis base index fell by a very similar 0.163°C.

The most prominent feature is the coolness of N America (except SW) and E Europe. Central Asia was very warm, but unusually in recent times, the Arctic was not. The oceans were mostly warm except for the ENSO region.

Here is the temperature map, using the LOESS-based map of anomalies. As promised last month, you now have a choice of proections. Robinson shows by default, but if you click the buttons at the bottom, you can cycle through Mollweide and ordinary let/lon.

As always, the 3D globe map gives better detail. There are more graphs and a station map in the ongoing report which is updated daily.

This post is part of a series that has now run since 2011. The TempLS mesh data is reported here, and the recent history of monthly readings is here. Unadjusted GHCN is normally used, but if you click the TempLS button there, it will show data with adjusted, and also with different integration methods. There is an interactive graph using 1981-2010 base period here which you can use to show different periods, or compare with other indices. There is a general guide to TempLS here.

The reporting cycle starts with a report of the daily reanalysis index on about the 4th of the month. The next post is this, the TempLS report, usually about the 8th. Then when the GISS result comes out, usually about the 15th, I discuss it and compare with TempLS. The TempLS graph uses a spherical harmonics to the TempLS mesh residuals; the residuals are displayed more directly using a triangular grid in a better resolved WebGL plot here.

A list of earlier monthly reports of each series in date order is here:

1. NCEP/NCAR Reanalysis report
2. TempLS report
3. GISS report and comparison with TempLS