Abstract:

The use of different climatological normal periods means the change of the evaluation results of meteorological elements, the abnormal state of climate events and their change characteristics, which have a substantial impact on the climate monitoring and prediction operations. Using temperature and precipitation observation data from national meteorological stations in Ningxia from 1981 to 2021, this study conducted a comparative analysis of the temperature and precipitation characteristics between the old climatological normal period (1981-2010) and the new climatological normal period (1991-2020). Additionally, it explored the changes in extreme characteristics of these factors. The results are as follows: Compared to the old climatological normal period, the annual and seasonal average temperatures in Ningxia are generally higher in the new climatological normal period, which is particularly evident in spring, summer and winter, and the frequency of abnormally high (low) temperatures increases (decreases) accordingly. Yinchuan, the western part of Wuzhong, and the northern part of Zhongwei are areas experiencing significant temperature increase. The overall intensity of extreme high (low) temperature has intensified (weakened), and their frequency has increased (decreased). In summer, the threshold and intensity of extreme high-temperature rise across various regions, especially in the central and northern areas, while in winter, the intensity of extreme low-temperature weakens in most regions, the amplitude of extreme low-temperature varies significantly. The average annual precipitation, as well as the summer, autumn and winter average precipitation, are greater in the new climatological normal period compared to the old. There’s an increased frequency of abnormally more precipitation in summer and autumn, whereas the opposite trend is observed in spring and winter. Meanwhile, the frequency of abnormally less precipitation in all seasons has decreased to some extents. There are significant spatial differences in seasonal precipitation, with a general increase in precipitation in summer and autumn, and a pattern of “decreasing in the north and increasing in the south” in spring and winter. The overall trend of extreme precipitation in spring and autumn (summer and winter) is intensifying (weakening), albeit with fewer (more) extreme precipitation events. In summer, the threshold and intensity variations of extreme precipitation are greater in the north and south, and smaller in the central region, with a notable increase in extreme precipitation in Shizuishan.

Key words: Ningxia, the new climatological normal period, the old climatological normal period, temperature, precipitation

摘要：

使用不同的气候态时段意味着对气象要素、气候事件的异常状况及其变化特征评价结果的改变，这对气候监测预测业务具有实质性的影响。利用1981—2021年宁夏国家级气象站气温和降水量观测数据，对比分析1981—2010年（旧气候态时段）与1991—2020年（新气候态时段）的气温和降水特征差异，并探讨了这些要素的极端性特征变化。结果表明，相比旧气候态时段，新气候态时段宁夏年均及四季平均气温普遍偏高，特别是春、夏、冬3季的平均气温增幅较明显，异常偏高（低）的频率相应增加（减小）；银川市、吴忠市西部和中卫市北部为气温增幅大值区；极端最高（低）气温强度总体增强（减弱）、频率增加（减小）；夏季各地极端高温阈值提高、强度增强，中北部地区尤为突出，而冬季大部地区极端低温强度减弱，但局地极端低温变幅较大。新气候态时段的年均及夏、秋、冬季平均降水量均多于旧气候态时段，其中夏、秋季降水量异常偏多频率增加，春、冬季则相反，各季降水量异常偏少的频率有不同程度的下降；季节降水空间差异明显，夏、秋季降水普遍增多，春、冬季则表现为“北减少、南增多”的格局；春、秋（夏、冬）季极端降水总体趋强（弱），但极端性降水事件趋少（多）；夏季极端降水的阈值和强度差异在南北地区较大、中部较小，石嘴山市的极端性降水明显增加。

关键词: 宁夏, 新气候态时段, 旧气候态时段, 气温, 降水