NOAA released
version 4 of the Global Historical Climatology Network - monthly (GHCNm) dataset in late 2018. GISS is switching to
v4 from v3 in March. Here we make a comparison of versions 3 and 4.
<> <> <> Land Data Only <> <> <>

In order to see more locally 250 km smoothing is used and no interpolations are made in the maps. The numbers on the top right are the area-weighted means over the grid boxes with data. (2019/02/22)
.
Comparison of the surface temperature integrated over the land using 1200 km smoothing. (12-month running means used).
.
Comparison of v3 and v4 for the month with largest difference in recent years.
.
<> <> <> Standard Land and Ocean Data Analysis <> <> <>
Our standard global mean temperature using ERSSTv5 for the sea surface temperature.
.
The annual mean temperature with Lowess smoothing.
.
The global distribution of surface temperature changes since 1900 and 1960 (many Antarctica station data start in the late 1950s)
.
Last 5-year and 11-year temperature distributions relative to 1951-1980 mean.
(2019/02/23)