By Dr. Robert Brown,
Physics Dept. Duke University
One of many, many problems with modern climate research is that the researchers seem to take their thermal reconstructions far too seriously and assign completely absurd measures of accuracy and precision, with a very few exceptions. In my opinion it is categorically impossible to “correct” for things like the UHI (Urban Heat Island) effect — it presupposes a knowledge of the uncorrected temperature that one simply cannot have or reliably infer from the data. The problem becomes greater and greater the further back in time one proceeds, with big jumps (in uncertainty) 250, 200, 100 and 40 odd years ago. The proxy-derived record from more than 250 years ago is uncertain in the extreme, with the thermal record of well over 70% of the Earth’s surface completely inaccessible and with an enormously sparse sampling of highly noisy and confounded proxies elsewhere. To claim accuracy greater than 2-3 K is almost certainly sheer piffle, given that we probably don’t know current “true” global average temperatures within 1 K, and 5K is more likely.