Change trend of extreme temperature in Northeast China for the past 50 years

The variation of extreme maximum(minimum) temperature and extreme high(low) temperature days were analyzed based on a dataset of daily highest and lowest temperature from 129 weather stations in Northeast China during 1961-2009.Results showed that annual extreme maximum temperature and annual extreme minimum temperature showed increasing trend in most parts of Northeast China,and the latter was more significant than the former,climate tendency rate respectively were 0.9℃/10a and 0.1℃/10a.The annual of extreme high temperature days revealed an increasing trend in Northeast China except some middle area,and it increased 0.8 days for average 10a.The annual number of extreme low temperature days mainly decreased with a rate of 4.7 days per 10a.In the past 49 years,there was no significant abrupt change point for both extreme maximum temperature and extreme high temperature days,and there was one point of discontinuity for both extreme minimum temperature and extreme low temperature days in 1982.