HadCrut4 surface
temperature data
are used by the IPCC.
Missing data are
a huge problem.
The dataset starts
in 1850.
For the first two years,
the only surface data
available for the
Southern Hemisphere
came from a single
weather station
in Indonesia.
At the end of five years,
only three weather stations
reported data in the
entire Southern Hemisphere.
Global averages
are calculated
from the averages
for each of the
two hemispheres.
Southern Hemisphere
data were insufficient.
Antarctica never achieved
20% coverage in any year,
and now has just over 10%.
50% coverage of the
Southern Hemisphere
wasn’t reached until
about 1950.
In the 1990s,
weather stations
at higher latitudes,
at higher elevations,
and in rural areas,
were selectively
removed from
the dataset
= potential bias
from deleting
weather stations
located in
cooler areas !
Data manipulation
was exposed in 2009,
and again in 2011,
in hacked eMails.
Comments from Forbes:
“Prominent scientists ,
central to the
global warming debate,
are taking measures
to conceal,
rather than disseminate,
underlying data
and discussions;
these scientists
view global warming
as a political “cause”
rather than a balanced
scientific inquiry;
and many of these
scientists frankly admit
to each other that much
of the science is weak
and dependent on
deliberate manipulation
of facts and data.”