Abstract:

Based on daily temperature data in Heilongjiang Province from 1991 to 2020, this study explored the temporal and spatial variations of the critical temperature of ≥10℃ at the beginning and the end of the day, as well as the parameter relationship and spatial-temporal distribution characteristics between the effective accumulated temperature of ≥10℃ and the longitude, latitude and altitude. The results showed that the correlation between the effective accumulated temperature ≥10℃ and the latitude, longitude and altitude in Heilongjiang Province had reached a very significant level, and the effective accumulated temperature geographic calculation model had a good simulation effect. During the study period, the initial date of the critical temperature ≥10 ℃ was in advance, the trend of advance was mountainous>plain, and the final date was delayed, the trend of delay was plain>mountainous. The advance of the initial day and the delay of the final day were conducive to the accumulation of effective accumulated temperature; during the study period, the effective accumulated temperature ≥10℃ showed an increasing trend, and its distribution showed obvious regional characteristics. In general, it gradually decreased from south to north, and gradually increased from mountains to plain.

Key words: Heilongjiang, DEM, 10℃ critical temperature, temporal and spatial variation