by Eric Worrall, November 22, 2017 in WUWT

Figure 1 shows one example of data derived from such proxy sources. The top panel of the figure shows a declining temperature trend over the 8,000-year period from the Holocene Climate Optimum to the modern warm period (left-hand scale). It also shows that this location experienced numerous cycles of warming and cooling that involved temperature changes of the order of two degrees Celsius.