为了更深入地了解贵州省气候变化的特征,运用19个气象站1959—2013年降水观测数据,分析了贵州省近55 a来的降水量、降水日数、降水强度的气候特征、变化趋势、空间分布和稳定性。结果表明:空间上,贵州省降水量南多北少,降水日数南少北多,二者呈空间负相关;时间上,近55 a贵州省降水大致可以分为1个平水期、2个丰水期和2个枯水期,降水增强区域面积逐渐缩小;季节差异性显著且随海拔高度增加而加剧;贵州省强降水日数和强度多年平均变化趋势不显著,空间上呈带状分布,最小值分布于威宁—毕节—遵义—三穗一带,但该区域暴雨强度变化率最大;贵州省大雨强度变异系数较小,但暴雨强度变异系数较大,且变异系数最大值分布于暴雨强度最弱的威宁—毕节—遵义—三穗一带。贵州省55 a间降水事件变化最突出的特征是:年均降水量、降水日数和强度相对较小的区域,其降水日数和强度的变化率最大、稳定性最差。针对这一特征应重点分析地形对贵州省降水的影响,加大对极端降水事件发生概率较大地区的降水动态及地质异动情况的观测。

In the aim of better understanding the characteristics of precipitation events in Guizhou Province,observed precipitation data during 1959-2013 collected from 19 meteorological stations were used in analyzing the climate characteristics, change trend, spatial distribution, and steadiness of precipitation, number of wet days, and precipitation intensity in the past 55 years in Guizhou Province. The results suggest that in spatial scale, the precipitation was more in the south than that in the north but the number of wet days was smaller in the south than that in the north, and the two quantities were in negative correlation in space. In temporal scale, one normal period, two wet periods, and two dry periods of the precipitation could be identified in the past 55 years in Guizhou Province, but intensified precipitation zones diminished in area; furthermore, seasonal variation was remarkable, which intensified with an increasing altitude. The number of intense precipitation days and the precipitation intensity were not notable in their mean annual change trend and the spatial distribution was of a belt pattern; the minimum values were distributed along Weining-Bijie-Zunyi-Sansui region, which was, however, characterized by the highest change rate of storm intensity. The coefficient of variation of heavy rain intensity in Guizhou was small but that of storm intensity was large, with the largest coefficient value found along Weining-Bijie-Zunyi-Sansui region where the storm intensity was the lowest. The most prominent characteristic of precipitation events in the 55 years in Guizhou was: regions with low annual average precipitation, small number of wet days, and low precipitation intensity had the highest change rate in number of wet days and precipitation intensity and the lowest stability. In view of this characteristic, the impact of topography on the precipitation in Guizhou should be paid emphasis to, and observation shall be strengthened on precipitation dynamics and geological abnormities in regions with a high probability of extreme precipitation events.