On 16 May 2012 we posted on temperatures in the Yamal peninsula. This is one of the sites much discussed for its influence on temperature reconstructions. In the earlier post we looked at measured temperature data from two stations. This time we have looked at a group of stations in and around the peninsula as shown in the following map. The data were from the station files used by the CRU for their CRUT3 temperature series.

We used the data from these station to cross-infill all of them. Two of them started before 1820 and eight others started in the 19th century. The method examined each pair of stations separately for each calendar month, calculated the correlation between them, then infilled missing data using whichever station had the best correlation and which had not itself been infilled.
As examples of the infilling we give below sample charts for 5 stations near to the peninsula: Salehard, MYS Kamennyj, Berezovo, Hoseda-Hard and Ostrov-Dikson. The most interesting chart we present is the last which is the estimated temperature for the Yamal peninsula based in the weighted average temperature of 6 stations in or near to the peninsula. This shows that the temperature has risen at about 0.56 °C per century but there is no sign of a sharp, 'hockey-stick' like upturn.



A recurring topic at ClimateAudit has been the use of tree ring data from the Yamal peninsula in Russia. Steve Mcintyre, the author of ClimateAudit, maintains that data from that area have been used selectively by researchers at the CRU to support the idea of a 'hockey stick' . At the RealClimate blog Gavin Schmidt claims that the results by the CRU were obtained after selection of samples following rigorous analysis of the data.

The Yamal peninsula is at around 71N 71 E. Below I plot data from two sites near to Yamal. One, Salehard, is 200 km south of the Peninsula and the other Ostrov Dickson is 200 km to the north east. The data were downloaded from the ClimateExplorer web site. There are few missing months in the data and I replaced them by the average of same calander month for the preceding and following year except for 2011 where I used the average of the temperature for appropriate calendar months.

As can be seen the observed data show no sign of a hockey stick. Both sites show a maximum in the 1940s, a minimum in the 1970s and and an increase since then - similar to the global temperature trend. One site, Ostrov-Dickson, does have a slight upturn this centruy but temperatures are still below those of the 1940s.

This comment was originally posted in the morning of 1 May 2012. It was modified during the course of day with the addition of the data for Ostrov Dickson.
See Older Posts...