There wasn’t any hockey stick prior to the year 2000.
The 1990 IPCC report showed that temperatures were much cooler than 800 years ago.
www.ipcc.ch/ipccreports/far/wg_I/ipcc_far_wg_I_full_report.pdf
Briffa’s trees showed a sharp decline in temperatures after 1940
The 1975 National Academy Of Sciences report also showed a sharp decline in temperatures after 1940
NCAR reported a sharp drop in temperatures after 1940
denisdutton.com/newsweek_coolingworld.pdf
The USHCN daily temperature data showed a sharp decline in temperatures after 1940
GISS graphs from the eastern Arctic showed a sharp decline in temperatures after 1940
Data.GISS: GISS Surface Temperature Analysis
GISS US temperature graphs showed a sharp drop in temperatures after 1940
NASA GISS: Science Briefs: Whither U.S. Climate?
The Directors of CRU and NCAR forecast a continuing drop in temperatures.
Hubert Lamb CRU Director : “The last twenty years of this century will be progressively colder“
http://news.google.com/newspapers/
John Firor NCAR director : “it appears we are going into a period where temperatures will be low and variable“
The CIA reported a sharp drop in temperatures, floods, droughts, dramatic climate change, and expansion of Arctic ice
www.climatemonitor.it/wp-content/uploads/2009/12/1974.pdf
Everyone agreed that temperatures had plummeted since 1940, and no one doubted that the tree ring data accurately reflected the decline in temperature.
So Hansen and Mann had a huge problem. They had to create a spike in temperatures, get rid of the tree-ring data, get rid of the Medieval Warm Period, get rid of the 1930s, get rid of the 1970s ice age scare, and get rid of the Little Ice Age.
Warming the 1970s didn’t make much sense, so they instead chose to cool the 1930s. Step one was for Hansen to whack a few tenths of a degree off the pre-1950 temperatures.
Black line is the 1975 National Academy of Sciences Northern Hemisphere plot. Red line is the current GISS northern hemisphere plot.
Hansen getting rid of the 1910-1940 warm period gave Mann cover to claim that something was wrong with Briffa’s trees – and throw them out. This opened the door for the creation of hockey stick.
Once the flood gates opened, they went nuts – erasing the MWP and LIA, erasing the 1930s and jacking up recent temperatures. All over the world, the past got cooler and the present got warmer.
Over the past decade, Hansen has made massive alterations to the historical US temperature record.
And now we have this completely manufactured temperature trend. The spike that we see is indeed Mann-made, and Hansen-made.
There was never anything wrong with Briffa’s trees. Mike’s Nature Trick was much worse than it seems. The red below shows the trees that were removed. They were very similar to the uncorrupted temperature graphs, and there was never a valid reason to doubt their accuracy.
The Deleted Portion of the Briffa Reconstruction « Climate Audit
Of course it is all good science, and all for the good of the planet.