Tag Archives: Hockey stick graph

Sloppy Science has a long history at the IPCC

The UN has been in charge of climate research since 1988 when the Intergovernmental Panel on Climate Change (IPCC) was formed.   The UN has been in charge of negotiating treaties on climate too.  When one agency has that much control over the process, the opportunities for mischief are almost endless.

The notion that the UN is the worldwide expert on anything scientific seems odd to me.  The UN is not where I normally go when  seeking scientific enlightenment.  But I suppose if one wants to mix science and politics together into some form of sciopolitical stew, it’s the perfect place to go.

There have been too many big  mistakes at the IPCC.  Last week I discussed the 2007 Himalaya Glacier debacle. It was a horrible mistake on a grand scale .  In December of 2009 it was Climategate.  The IPCC has been sloppy for a long time.  My favorite is the 2001, Hockey Stick Graph event, sloppy science in the extreme.

Chapter 7 of the 1990 IPCC Climate Assessment is titled Observed Climate Variation and Change.  Back then the IPCC described in detail weather going back 600,000 years.  A discussion of the Medieval Warming Period and the Little Ice Age was a part of their evaluation.  Multiple graphs were included, with one covering the last 1000 years.  Here is that graph from page 202 of the report:

This graph and others like it were causing problems for the IPCC. If it was warmer 1000 years ago (and 6000 years ago too on a different graph), how could the IPCC be sure the warming we were seeing today was man caused?

In 1998 a small miracle appeared.

Michael Mann and others published a new study in Nature that showed rapid 20th century warming.  The study included a 600 year long temperature reconstruction. Another 400 years was added in a second graph in 1999.  That 1000 year long graph became known as the Mann Hockey Stick Graph.  Ta Da, the graph:

The same 1000 years, two very different graphs.  The Mann graph was magical.  In one single piece of research….Poof… the Medieval Warming Period and the Little Ice Age were gone. How convenient for the IPCC.

In 2001, the IPCC released its 3rd Climate Change Synthesis Report..  It featured the Mann Graph and the graph became the rage of the climate science community. Pro global warming scientists from all over the world adopted the graph.

Other studies that contradicted the Mann report were mysteriously missing form the IPCC Synopses.  The IPCC had just rewritten climate history based upon a single unsubstantiated piece of data that was brand new.  One sloppy WAG, and wrong too.

The Mann study turned out to be flawed.  It has been challenged both mathematically and scientifically.  But even if it had been accurate it was arrogantly sloppy science.  The study was too new and too untested to be adopted so quickly. Pro global warming advocates all over the world liked the results…it was the proof they needed …so they ran with it.

Look at the data.  There is very little fluctuation in data until 1900 (which  contradicted earlier studies) and then it went nuts.  Mann would later claim (in a March 2005 Scientific American article) that the Medieval Warming Period and the Little Ice Age were regional events. But he was graphing the northern hemisphere, the very region in question.

Earlier studies predicted single century changes of as much as 2 degree C., but not the Mann study.  The data never varied by more than .3 degree C in the first 900 years of the study. The data changed shape at the boundary layer between the  two main data sets (blue and red data sets), always a red flag.  A sudden change in shape that coincides with new data being used is an indication that the data sets might not be properly calibrated.   The IPCC featured the graph and then insisted they were right.  Sloppy, sloppy, sloppy.

In the 1992 Synopses Report, the IPCC predicted a .3 degree C increase in temperatures per decade  (using 1990 as a baseline) with a 1 degree C increase by 2025.  In the 2007, the Synopses Report  predicted a .2 degree C increase from 2000 levels by the end of the decade with another .2 degree C increase by 2020.  They had in effect cut their predicted temperature rise by a third after an additional 15 years of study.   Obviously the first estimate must have been a wild ass guess.  And the second guess has been too high to….at least so far….sloppy science, the IPCC way.