USHCN raw temperature data shows a sharp rise in temperatures after 1970.
I did some analysis on this, and discovered that since 1970, NOAA has been losing December data much faster than they have been losing July data. This causes post-1970 temperatures to be skewed upwards.
If I plotonly stations with complete records for the year, the post-1970 peak gets reduced.
via The Deplorable Climate Science Blog
February 17, 2019 at 12:07PM
Iowa Climate Science Education 