Is the cold region in Northeast China still getting warmer under climate change impact?

Abstract

Abstract Whether there is an obvious “hiatus” of warming at the global or regional scale is an outstanding issue, which has attracted worldwide attention. To investigate the response of temperature variation to global warming in Northeast China, it is necessary to reanalyze whether the regional warming trend has slowed down. Heilongjiang Province, located in the cold region in Northeast China, was selected as the study area. Based on the meteorological data recorded at 26 meteorological stations from 1960 to 2015, the spatiotemporal characteristics of temperature in this region were analyzed using the Mann-Kendall trend analysis, Sen's slope method and inverse distance weighting (IDW) method, and then compared with the temperature variations of the globe and mainland China. Furthermore, the cross wavelet method was applied to explore the teleconnection between temperature and large-scale climate patterns to investigate possible causes of temperature variations of this region. The results demonstrated that: 1) the spatial distribution of temperature showed latitudinal variations, and annual and seasonal temperatures showed warming trends, among which the warming trend in autumn was the most significant and the variation range in winter was the greatest. 2) In term of net temperature, global warming might have greater impacts over the central, western and northwestern parts of Heilongjiang Province. 3) Compared to the temperature variations of the globe and mainland China, hiatus phenomenon was detected in Northeast China, for there was an obvious cooling trend in spring. 4) Arctic oscillation (AO) was a key factor affecting the temperature change in this cold region and Pacific decadal oscillation (PDO) could be another closely-related climatic factor contributed to this hiatus period.