河西走廊东部武威市2021年主要气候特征及影响分析

Main Climatic Characteristics and Its Impact Analysis of Wuwei in Eastern Hexi Corridor in 2021

2021年武威市气候较为异常,气温冷暖变化显著,极端天气事件多。全市平均气温8.2℃,较历年偏高1.1℃,为有气象记录以来最高,2月、7月、9月气温打破历史同期极值;≤-20℃的低温日数和寒潮次数偏多。降水时空分布不均,年降水量为270.5 mm,较历年偏多3%,凉州、古浪分别偏多22%、11%,民勤、天祝分别偏少17%、7%;4月偏多202%,7月偏少58%。日照时数为2 664.9 h,较历年偏少6%;≥35℃高温日数多,持续时间长,伏期干旱造成农作物受灾;受汛期降水偏少的影响,2021年石羊河的年平均流量较2020年同期偏少9%,全市归一化植被指数NDVI差于2020年同期。大风沙尘天气偏多,沙尘暴为2007年以来最多,风沙造成农作物受灾,2021年大气降尘量较2020年同期偏多17%,可吸入颗粒物PM10浓度较2020年同期上升了61.6%,城市空气质量严重污染,影响交通运输和大棚作物和日光温室瓜果蔬菜生长。短时强降水出现时间早,局地暴雨多,引发灾害。

The climate in Wuwei in 2021was quite abnormal, with significant changes in temperature, and many extreme weather events.The annual average temperature was 8.2℃,and higher than the normal year by 1.1℃,which was the highest since meteorological records began. The temperature in February,July and September broke the record for the same period. The number of ≤-20℃ low temperature days and cold wave times were more. The precipitation spatio-temporal were distributed unevenly,The annual precipitation is 270.5 mm, 3% more than the normal years, which 22%, 11% more in Liangzhou and Gulang County, and 17%, 7% less in Minqin and Tianzhu County,which 202% more in April and 58% less in July. The annual sunshine hours were 2 664.9 hours, 6% less than the normal year. The high temperature days ≥35℃ were more, which duration were longer, and the crops were damaged by the summer drought. Affected by less precipitation during the flood season, the average annual flow of 2021 was 9% less than that of the same period in 2020 in Shiyang River. The NDVI was worse than that of the same period in 2020.Windy dusty weather were on the high side,sandstorm were the highest since 2007, which caused disaster to crops. The atmospheric gust fall in 2021 was 17% higher than that of the same period in 2020, and the particulates PM10 concentration was 61.6% higher than that of the same period in 2020. The urban air quality was seriously polluted, which affected the traffic transport, greenhouse crops and solar greenhouse fruit and vegetable growth.The short-term strong precipitation appeared early and local rainstorm was much, which caused disaster.