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Abstract: Based on daily mean surface temperature data of 18 meteorological stations over Shandong province during 1961—2008, the thresholds of extreme high and low temperature events have been determined for each station by the centesimal value method, and then, the spatial characteristics and temporary trends of extreme temperature frequency for recent 48 years have been analyzed. The results show that there was a great spatial difference in both annual extreme high and low temperature frequency over Shandong Province and the highest frequency regions were mainly distributed in Jiaodong Peninsular. However, the difference values of annual extreme high and low temperature frequency in between high-value and low-value areas were all small and the mean annual extreme high and low temperature days were mostly 15~16d/a. Whether at the annual or seasonal scales, there was an increasing trend in extreme high temperature frequency, which was most significant in spring, while there was a decreasing trend in extreme low temperature frequency, which was most marked in winter. Annual changes in extreme high and low temperature frequency show obvious spatial variations, which were more remarkable in Jiaodong Peninsular in contrast to the west of Shandong Province. For recent 48 years, the abruptions in the annual time series of extreme high and low temperature frequency were found in all stations but Haiyang Station for extreme high temperature frequency and their trends were more significant since 1990s. In addition, fluctuation changes were found in annual extreme high and low temperature frequency with a quasi-5-year period.
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Received: 16 August 2010
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Corresponding Authors:
Dejuan Jiang
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2011, Vol. 29 
