The Extreme Value Analysis Of The Minimum Temperature Over Recent50Years In Changchun

In this paper, by calculating and analyzing the extreme temperature indices that includes the daily minimum temperature and daily maximum temperature data of24Climate Sites in Changchun over the past47years from1961to2007, we explored the changes of extreme temperature events in Changchun. The results indicate that both the minimum and maximum temperatures have significantly increased from1961to2007, and the minimum temperature has changed greater than the maximum temper-ature, according to almost all the temperature indices. That is, the number of cold events tends to decrease, while the number of warm ones tends to increase which is less than the cold ones. By fitting several different models, such as the GEV model, the GPD model and the declustering GPD model, we discussed the minimum daily mini-mum temperature data in Changchun’s24sites, and estimated10-year return level. We also made a sequence’s trend test for the minimum daily minimum temperature (TNn) dataset. It was found that the minimum daily minimum temperature in Changchun had significantly positive trends, with a magnitude of0.089°C/a.