Dating age range graph

This is his Fig 5: Easterbrook plots the temperature data from the GISP2 core, as archived here. However, the GISP2 “present” follows a common paleoclimate convention and is actually 1950.

The first data point in the file is at 95 years BP.

Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. This data ends in 1855, long before modern global warming began.

This would make 95 years BP 1855 — a full 155 years ago, long before any other global temperature record shows any modern warming.

In order to make absolutely sure of my dates, I emailed Richard Alley, and he confirmed that the GISP2 “present” is 1950, and that the most recent temperature in the GISP2 series is therefore 1855. He wants to present a regional proxy for temperature from 155 years ago as somehow indicative of present global temperatures.

The top of the core is accurately dated by annual dust layers at 1987.

There has been no significant warming from 1987 to the present, so the top of the core is representative of the present day climate in Greenland. He was kind enough to supply me with a temperature reconstruction for the GRIP drilling site — 28 km from GISP2.

Thus, regardless of which year ( 1934, 1998, or 2010) turns out to be the warmest of the past century, that year will rank number 9,099 in the long-term list.

The climate has been warming slowly since the Little Ice Age (Fig.

Jason Box is one of the most prominent scientists working on Greenland and he has a recent paper reconstructing Greenland temperatures for the period 1840-2007 (Box, Jason E., Lei Yang, David H. It’s obvious that the GRIP site is warmer than GISP2 (at Summit Camp).

The difference is estimated to be 0.9ºC on the annual average (Box, pers comm).

With the exception of a brief warm period about 8,200 years ago, the entire period from 1,500 to 10,500 years ago was significantly warmer than present.

This is Easterbrook’s Fig 4: It’s a graph he’s used before, in various forms, almost certainly copied and altered from the original (click image below to see source: the NOAA web page for Richard Alley’s 2000 paper Another graph of temperatures from the Greenland ice core for the past 10,000 years is shown in Figure 5.

The bottom black line shows his 1855 “present”, and it intersects the red line in the same places as his chart.

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