The temperature graph dubbed the “hockey stick” (HS) was designed to rewrite history by eliminating the Medieval Warm Period (MWP) because it contradicted the Intergovernmental Panel on Climate Change (IPCC) claim the 20th century was the warmest ever. As Lord Monckton explains,
“Dr. McIntyre’s account of the systematically dishonest manner in which the “hockey-stick” graph falsely showing that today’s temperatures are warmer than those that prevailed during the medieval climate optimum was fabricated in 1998/9, adopted as the poster-child of climate panic by the IPCC in its 2001 climate assessment, and then retained in its 2007 assessment report despite having been demolished in the scientific literature.”
It did more damage than generally discussed.
A major problem and serious limitation in climate science is the amount and nature of data. Temperature measures come from a variety of sources so creating meaningful continuous records is very difficult. The Hockey Stick fiasco underlined this, but what they did possibly deters many from taking up the problem. In his autobiography Hubert Lamb said he founded the Climatic Research Unit (CRU) in 1972 because,
“it was clear that the first and greatest need was to establish the facts of the past record of the natural climate in times before any side effects of human activities could well be important.”
He was right and nobody did more to reconstruct the past. Ironically, his graph with the MWP in the first two IPCC Reports triggered the HS. Due to misplaced funding for data collection and corrupted research, it is worse now.
Temperature data comes in two forms; direct instrumental measurement or a secondary indicator known as a proxy temperature. Proxies are used by paleoclimatologists and include ice cores, tree rings, lake sediments (varves), pollen counts, or anything that results from temperature or precipitation changes.
Another challenge in obtaining measures of temperature is the problem of reconstructing a continuous temperature record. Traditionally, climate has recognized three periods.
- Most recent is the instrumental (secular) period that some claim covers 150 years, but in reality is inadequate for the entire period. Temperatures are measured by half a degree Celsius so any other temperature number is a statistic. Accuracy is also a problem. CRU Director Phil Jones’s claimed an increase of 0.6°C in the last 130 years, but with an error range of ±0.2°C.
- Historic records cover approximately 3000 years. They include everything from information on the walls of Pharaohs tombs to crop reports such as the remarkable wine harvest record used in Times of Feast, Times of Famine by Emmanuel Le Roy Ladurie or the Hudson’s Bay Company (HBC) records I used to reconstruct almost 300 years. At best accuracy of 1°C is possible.
- This is the largest sector covering most of the Earth’s history and includes proxy indicators from biologic and geologic sources. Levels of accuracy decrease and the error factor increases going back in time. Even if you get a reasonable temperature estimate you must have an accurate date. Good materials and skilled hands can yield ages that are certain to within 1 percent, even in rocks only 10,000 years old, in which quantities of 40Ar are vanishingly small. But 1 percent of 1 million years is 10,000 years and we have emerged from an Ice Age in that time. Even radiocarbon dating used for dates over 65,000 years, have a relatively wide error factor.
Some proxies cross these boundaries and are therefore valuable. Tree rings are one of these and provide a transition across all three. Particularly appealing are Bristlecone Pines because the oldest is 4,789, but they were problematic because growth is primarily controlled by precipitation. The hockey stick gang assumed annual growth rings were due to temperature when most are about precipitation levels. I was involved in early work to make links. Dendroclimatologist Joel Guiot used the HBC temperature record I created for Churchill, Canada in his 1986 paper. His objective was to create a regression formula by comparing the temperature record with tree rings for the modern record, then use it to provide temperature records from past tree rings. He detected an 18.6 and 22-year cycle. The problem is I also detected a 22 year cycle but in the precipitation pattern. This matched with evidence from other sources, especially other tree ring records.
Guiot’s attempt to create a regression formula against the modern instrumental record has promise for the right variables. The Hockey Stick people did it differently they tacked the modern temperature record on to the tree ring record. In his great book, The Hockey Stick Illusion A.W. Montford says,
“The inclusion of the instrumental record was instantly controversial, with global warming skeptics accusing Mann of having spliced two entirely different data sets.”
Mann said they were not spliced but overlaid. The leaked email from Phil Jones to Ray Bradley on 16 November 1999, revealed the overlay was the now infamous “hide the decline” or “Mike’s trick”. Tree ring data showed decline in the 20th century so the addition from Jones’ temperature record solved the problem. It was visually effective providing the sharp up turn of the hockey stick blade. Leaked emails were sensational but more telling were the leaked computer codes. They show how the computer was programmed to amend any undesirable trend.
Billions were wasted on climate research to prove the AGW hypothesis, including those used to create the hockey stick. Understandably politicians angered by misuse of funding to create deceptive science are canceling the grants. Researchers will be loathe to pursue similar valuable research and unlikely to get funding. It is minor collateral damage compared to the energy policies built around the false science, but damage to progress in understanding climate nonetheless.