In 1975, the National Academy of Sciences showed no net Northern Hemisphere warming from 1900 to 1970, and about 0.5C cooling from the 1930’s to 1970
But this didn’t make climategate scientists happy, because it wrecked their global warming theory, which their livelihood depends on.
From: Tom Wigley <wigley@ucar.edu>
To: Phil Jones <p.jones@uea.ac.uk>
Subject: 1940s
Date: Sun, 27 Sep 2009 23:25:38 -0600
Cc: Ben Santer <santer1@llnl.gov>It would be good to remove at least part of the 1940s blip, but we are still left with “why the blip”.
So NCDC made the most of the 1930’s/194o’s warmth disappear.
The next graph is an overlay of the 1975 NAS graph on the current NCDC graph, normalized to the most recent years.
They pulled their standard trick of cooling all pre-1963 temperatures.
This animation shows their data tampering to hide the “1940s blip”
According to Hansen 2001, time of observation bias adjustments are not needed in global measurements.
This time of observation correction, ….is not generally required in the rest of the world, because the systematic shift from once a day evening to once a day morning observations which occurs at U.S. cooperative observer stations is not characteristic of most global observations [Easterling et al., 1996b].
So why the data tampering by Team Climategate?
It would be good to remove at least part of the 1940s blip, but we are still left with “why the blip”.