Land temperatures
are not easy
to measure.
The first problem is most of the
land on our planet is not inhabited,
so there are no weather stations
located there.
Then there are repeated changes
in measurement instruments.
From mercury bulb thermometers,
to semiconductors.
Weather station sites move too.
And there is economic growth
in the vicinity of weather stations,
adding cement, asphalt, buildings,
roads, cars, trucks, airplanes, etc.
Example:
Dallas Love Field Airport has had a
weather station reporting monthly
since 1940.
Love Field was originally an airport
near a small city -- Dallas had
400,000 people, and the airport
had three daily flights.
It grew to be a large urban airport,
with 200 daily flights.
Along with all the building, and activity,
came local warming of +2.9 ° F since 1940.
But Centerville, Texas had far fewer
land use changes – their temperature
now averages -0.3 °F less than in 1940.
To avoid the urban heat island effect that
causes warming from economic growth,
unrelated to CO2 in the air, in 2002
the National Oceanic and Atmospheric
Administration (NOAA) set up
114 rural temperature monitoring stations
in the US ( aka "USCRN" ).
Those weather stations
show no persistent increase
in US temperatures -- 2018
was -0.3°F colder than the
first two years measured.
February and March 2019, combined,
were the coldest two-month period
ever recorded by the USCRN
( since 2002 ).
US rural temperatures are stable,
and that pattern has been identified
all around the globe --
"warming" often "disappears"
after the weather stations
"warming" often "disappears"
after the weather stations
affected by land use changes
are eliminated.