气候变化情景下华北地区干热风的时空分布特征

 干热风是影响华北地区冬小麦生长发育及产量形成的重大农业气象灾害之一。本文利用区域气候模式PRECIS生成的A2和B2情景下华北地区的逐日气象数据,分析了2011—2050年共40a的干热风日数及分异规律。结果表明,在PRECIS的预测中,高排放A2情景下的干热风日数为6.5d,呈中西部偏高南北两侧及沿海偏低的趋势。除最南端的个别地方外,大多数区域的干热风日数呈增加趋势,增加最大速度为0.145d/a；中低排放B2情景下干热风日数为6.0d,区域分布趋势与A2情景的类似,也呈中西部偏高南北两侧及沿海偏低的趋势。B2情景下,平原西南一带的干热风呈轻微下降趋势,东北部则呈小幅增加的趋势,但幅度小于A2情景。本研究对未来气候变化情景下干热风农业气象灾害的变化趋势进行了分析,以期为区域未来的防灾减灾工作及相关政策的制定提供参考。

Temporal and Spatial Variations of Dry-hot Windy Days in the North China Under the Condition of Climatic Change in the Future

Dry Hot Windy Day (DHWD) is one of the main agrometeorological disasters happend in the north China area which could cause the serious yield loss of winter wheat. Using daily weather data created by RPECIS, which is the one of most widely used regional climate models developed by Hadley Center, DHWD in the future SRES A2 and B2 climate change scenarios is analyzed. Results show that PRECIS predicts DHWD for A2 scenario is 6.5 days/year, and is lower in coastal, north, and south areas, but higher in the middle west area. DHWD is increase in most areas except the far southern area, the maximum increase rate is 0.145 day/year; for B2 scenario, DHWD is 6.0 day/year, with similar regional distribution trend of A2, i.e., higher in the middle area and lower in the other areas. DHWD is slightly decrease in southwest area and a little increase in northeast area; however increase rate is much lower than that for A2. The trends and variations of DHWD in the future for both SRES A2 and B2 scenarios are analyzed. Results are able to serve as the argometeorological disaster prevention and reduction, and make the contribution to the relative policy making.