The 1990 IPCC Report showed Arctic sea ice increasing since the early 1970s, but the 2001 report reversed the increase into a decrease.
archive.ipcc.ch/ipccreports/tar/wg1/062.htm
Part of this treachery was including the largest freshwater lakes in the world into their sea ice calculations.
Updated digitised ice data for the Great Lakes are also included
They also erased the Medieval Warm Period And Little Ice Age, and replaced it with the Hockey Stick.
Climate Change 2001: The Scientific Basis
An important part of this process was to hide the decline shown in Briffa’s reconstruction, which closely resembled the 1974 NCAR graph.
21 Jul 1974, 13 – The Des Moines Register at Newspapers.com
This required erasing the “1940’s blip”
