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[1] Many have made efforts to clarify the climatic significance of stable isotopic variations in ice cores around central Asia through the study of stable isotopes in present-day precipitation. A new shallow ice core from Muztagata, in the eastern Pamirs, allows for a detailed comparison of annual d 18 O variation with local meteorological data as well as with global air temperature variations. On the basis of a comparison of seasonal fluctuations of d 18 O in the local precipitation, the 41.6-m ice core drilled at 7010 m provides a record of about one-half century. The annual fluctuations of d 18 O in this ice core are in good agreement (correlation coefficient of 0.67) with the annual air temperature changes at the nearby meteorological station Taxkorgen, indicating that the isotopic record from this ice core is a reliable temperature trend indicator. The most important discovery from the d 18 O variation of this ice core is a rapid warming trend in the 1990s, which is consistent with a general global warming trend over this time period. This recent rapid warming at higher elevations in this area has led to the quick retreat of alpine glaciers.Citation: Tian, L

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During 1977During -1981 the Beijing (BJ) meteorological station was at a suburban location. In 1981 it was moved to a more urban location, but in 1997 it was subsequently moved back to the same suburban location. The daily BJ temperature series, together with those from 18 nearby stations, form a unique database for studying how site-change and possible urbanisation influences affect climate changes at a local scale. The site-change-induced biases were quantified, between 0.43 and 0.95°C, based on comparisons between multi-year-mean seasonal temperature anomalies at BJ and the mean of those from a cluster of nearby stations. The annual mean urban-suburban difference was 0.81°C around 1981 and 0.69°C around 1997, indicating a growing urbanisation effect in the suburban compared to the downtown area. The linear warming trend in the adjusted (for site moves only) BJ temperature series during 1977-2006 was 0.78°C/decade. Comparing with several rural and less-urban sites, we suggest that the BJ records include an urbanisation-related warming bias between 0.20 and 0.54°C/decade, likely about 0.30°C/decade, for the recent few decades. The climatic warming at BJ between 1977 and 2006 is likely, therefore, to be about 0.48°C/decade. Caveats for using these estimates were discussed.