利用1961—2019年青海省42个气象站逐日最低气温，分析不同等级寒冷日数时空演变特征。结果表明：（1） 1961—2019年青海省寒冷日数随着等级降低而逐渐增加，主要以微寒日数为主；总寒冷日数整体呈减少趋势，显著快速减少的突变发生在1995年；总寒冷日数减少主要是由酷寒日数的减少引起；1997年气候突变后严寒、大寒、小寒、轻寒、微寒和总寒冷日数变化趋势减少，酷寒日数变化趋势增多，极寒和凉日数变化趋势减少与增加分布相当。（2） 青海省寒冷日数表现出明显的空间差异，总寒冷日数随着海拔升高逐渐增加，等级较高的寒冷日数增减趋势较明显，随着寒冷等级的降低，增减趋势向低纬度和海拔相对较低的地区发展。（3） 极寒、酷寒、严寒、轻寒、微寒和总寒冷日数随年平均气温升高而逐渐减少，大寒、小寒和凉日数随年平均气温升高而逐渐增加。（4） 青海省除了严寒日数其余等级寒冷日数存在持续性，未来下降趋势将持续，但持续性强度不尽相同。

Based on the daily minimum temperature measured at 42 meteorological stations in Qinghai Province from 1961 to 2019, the spatial and temporal evolution of different grades of cold days (extreme cold, extremely cold, severe cold, major cold, minor cold, light cold, slightly cold, cool) were analyzed. The results showed that: (1) From 1961 to 2019, the number of cold days in Qinghai Province gradually increased with decreasing levels, mainly dominated by slightly cold days. The total number of cold days showed an overall decreasing trend, with a significant rapid decrease occurring in 1995. The decrease in total cold days was mainly caused by the reduction in extremely cold days. After the climate abrupt change in 1997, the trends of severe cold, major cold, minor cold, light cold, slightly cold, and total cold days decreased, while the trend of extremely cold days increased. The trends of extreme cold and cool days decreased and increased respectively, with a distribution roughly equal. (2) Qinghai Province exhibits significant spatial differences in cold days, with the total number of cold days gradually increasing with altitude, and the trends of higher-level cold days are more pronounced. As the level of coldness decreases, the trends of increase and decrease develop towards lower latitudes and areas with relatively lower altitudes. (3) The numbers of extreme cold, extremely cold, severe cold, light cold, slightly cold, and total cold days gradually decrease with increasing annual mean temperature, while the numbers of major cold, minor cold, and cool days gradually increase with increasing annual mean temperature. (4) Except for severe cold days, the numbers of other levels of cold days in Qinghai Province show persistence, and the downward trend will continue in the future, but the strength of persistence varies.