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Bring the Proxies Up to Date!! "I will make here a very simple suggestion: if IPCC or others want to use “multiproxy” reconstructions of world temperature for policy purposes, stop using data ending in 1980 and bring the proxies up-to-date."
This question was posed to Michael Mann at Realclimate His reply: "Most reconstructions only extend through about 1980 because the vast majority of tree-ring, coral, and ice core records currently available in the public domain do not extend into the most recent decades. While paleoclimatologists are attempting to update many important proxy records to the present, this is a costly, and labor-intensive activity, often requiring expensive field campaigns that involve traveling with heavy equipment to difficult-to-reach locations (such as high-elevation or remote polar sites)."
For many of the tree-ring proxy sites, the calculated tree-ring temperature proxies diverge sharply from the actually-measured temperatures in the late 20th century: for example see Juckes et al. 2006 and Briffa’s Tornetrask Reconstruction. This calls into question the accuracy of tree-rings as a proxy for temperature. The contortions of the "Hockey Team" to account for the Divergence Problem make amusing reading: "What critics have observed and Juckes doesn’t discuss is that the average of 387 “temperature-sensitive” sites goes down in the last half of the 20th century (the Divergence Problem). But within the population of 387 sites, you can find some that go up. And surprise, surprise, the Team chooses them over and over. Tornetrask is used in every study. Juckes has taken cherry picking to a new height by even using it twice (Tornetrask and Fennoscandia, well disguised by the use of different lat/longs.)" —Steve McIntyre
Steve McIntyre recently undertook fieldwork near Colorado Springs to update the Graybill and Idso (1993) proxies of (mostly) stripbark bristlecone pines — and to test the "the Starbucks Hypothesis: could a climate scientist have a Starbucks in the morning, collect tree rings through the day and still be home for dinner?" Both missions were accomplished, and the resulting tree-ring data promptly archived. Heavy equipment was not required, and the entire Almagre resampling program cost about $4,000, paid for by CA readers contributions.
