LIU Dan1，ZHAO Jingbo1,2
（1. College of Tourism and Environment，Shaanxi Normal University，Xi’an 710062，China；
2.National Demonstration Center for Experimental Geography Education, Shaanxi Normal University, Xi’an 710062，China；
3.State Key Laboratory of Loess and Quaternary Geology，Earth Environment Institute，Chinese Academy of Science，Xi’an 710075，China）
Abstract: Based on the daily temperature data for the period of 1955~2013 from Harbin station，Shangzhi station，and Tonghe station，11 common climate indices were analyzed by using linear trend method，anomaly and accumulative anomaly method，Morlet wavelet analysis，main component analysis, correlation analysis and Mann-Kendall test. Results show that, temperature of summer，autumn，and winter in Harbin are rising; winter temperature has increased significantly，while the spring temperature has an obvious reduction at a rate of 0.60 ℃/10a; The annual average temperature，annual average minimum temperature，and annual average maximum temperature have increased，and the annual average minimum temperature has the largest rise. Six indices including annual extreme maximum temperature，annual extreme minimum temperature，summer day，hot night，warm night，warm day are on the rise; five indices including ice day，frost day，cold night，cold day，annual temperature range are on the decline. Annual extreme maximum temperature，annual extreme minimum temperature and warm night with high rate of change have a first main cycle for about 28~30a and second main cycle for about 17~18a second main cycle; cold night has short cycles for 3a，6a and 8a. Results of principle component analysis shows that changes of high load indices including warm night，cold night and warm day are probably the main reasons for Harbin’s temperature change. Correlation matrix shows that correlations of relative index are extremely significant；each warm index or cold index is positively correlated with other warm or cold index，but each warm index are negative correlated with and each cold index. From Mann-Kendall test，the mutations of three cold indices including ice day，cold night and cold day mainly occurred in 1970s and 1980s，other indices’ mutation mainly occurred during 1990~1999. On the whole，the average temperature in Harbin has increased with a rate of 0.32℃/10a，temperature rising rate is higher than the national average temperature rising rate of 0.26℃/10a. Results concluded from this paper can provide theoretical basis for disaster prevention and reduction.
Key words: Harbin region; extreme temperatures; major indices; cycle laws; mutation time
EARTH AND ENVIRONMENT Vol.45, No.6, Tot No.320, 2017, Page 587-599
