In 1940 scientists reported 10 degrees Arctic warming, and a reduction in polar ice thickness.
In 2000, climate scientists a similar warming and ice loss, indicating that Arctic climate is cyclical.
August 29, 2000
The end of the cold war, for instance, has brought to light important sonar measurements of Arctic ice collected by United States Navy submarines. They are being analyzed by Dr. Drew Rothrock at the Applied Physics Laboratory of the University of Washington in Seattle. By comparing measurements of ice thickness between 1958 and 1976 with data from 1993 and 1997, he determined that the thickness had decreased from 10.2 feet in the early period to 5.9 feet in the 1990’s.
In reporting that parts of Alaska and northern Eurasia had warmed by nearly 11 degrees in winter months the past 30 years, Dr. Serreze observed, ”We have climate evidence from the past four centuries gleaned from ice cores, lake cores and tree rings that don’t show nearly as dramatic warming, putting the modern record into context
PIOMAS conservatively reports 5.6 feet in 2012 and 6.2 feet in 2015. The Navy reports much greater thicknesses.
Plotting the data out, what becomes clear is that the Arctic is cyclical.
This cooling and increase in ice was reported by scientists at the time
National Academy Of Sciences Science News
So how did NASA deal with this cyclical behavior and post 1940’s cooling? They simply made it disappear.