Newest Reconstruction: PAST 4000 YEARS OF GREENLAND TEMPERATURE

Fulford Harbour, Saltspring Island (BC, Canada) – November 17, 2011 – Frosty…

Adding to my previous post (Unprecedented Global Warming Not Unprecedented), the renowned scientific peer-reviewed publication ‘GEOPHYSICAL RESEARCH LETTERS‘  just published (Nov 10, 2011) a new reconstruction of temperatures in Greenland for its past 4,000 years:  VOL. 38, L21501, doi:10.1029/2011GL049444, 2011.

I find regional data always interesting, as “global average temperatures” often statistically hide the regional swings.  (Regional climates change “unsynchronized” across the planet.)  This latest reconstruction clearly shows the Little Ice Age, from which we’ve simply been recovering these past 150 years, as far as I can tell.  Also -again obvious- in this latest reconstruction are the fairly recent significantly warmer periods, including the Roman and Medieval Warm Periods.  (See graph below)

From the introduction [For the cited sources, see the original.  My emphasis]:

“… Greenland surface temperature is a key parameter for Greenland ice sheet mass balance, and thus for global sea level and ocean circulation. … Recent rapid warming and subsequent  ice‐melt in Greenland is estimated to account for 4– 23% of  global sea level rise for the period of 1993– 2005. … However, the Greenland temperature  trend diverges from the global trend in the last 168 years,  which raises the possibility that much of the trend is due to natural variability, and makes it more difficult to attribute the recent warming in Greenland to increasing anthropogenic  greenhouse gases in the atmosphere … . For example, according to observed  temperature records, Greenland underwent a 33% larger  warming in 1919– 1932 than the warming in 1994– 2007 …, and recent decadal average temperature is  similar to that of the 1930s– 1940s … . A deviation of the Greenland temperature  from the global average temperature trend is likely caused by  regional climate variability via modes such as the North Atlantic Oscillation/Arctic Oscillation (NAO/AO) and the Atlantic Multi‐ decadal Oscillation (AMO) … . These twentieth  century oscillations are thought to be induced by the internal variability of climate system … . As our  understanding of climate variability is limited by relatively  short observational records, it is critical to develop a longer  precise temperature record with tight age control.  …”   Like the one they just published:

 The reference line for “present temp.” for that ice core drill location is −29.9°C, based on the 2001–2010 record warm period, making the findings all that more striking.  Pretty easy to “break records” all over the map after an unusually cold 500 years…

See the paper in full available on Leif Svalgaard‘s site: http://www.leif.org/EOS/2011GL049444.pdf

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