区域旱情实时评估方法研究

Study on real-time evaluation of regional drought

干旱灾害是我国出现频率高、持续时间长、波及范围大的自然灾害之一,及时准确的旱情评估有利于及时做好抗旱准备,减少和避免干旱灾害带来的损失。但干旱作为一种复杂的现象,仅仅使用旱情指标不能全面地反映旱情的严重程度,旱情评估难度大。基于分布式水文模型计算SMAPI(Soil Moisture Normally Percentage Index)干旱指标,使用逐日滑动统计方法实现干旱等级的实时评估,结合土地利用数据对不同土地利用的受旱面积进行统计,并利用面积图法分析不同干旱等级的持续时间,形成综合考虑干旱指标、土地利用和干旱持续时间的旱情实时评估方法。通过在研究区域的旱情评估结果表明,该方法进行旱情实时评估的结果与历史旱情量化结果基本一致,能够较好地反映区域的实际旱情。

Drought disaster is one of the natural disasters with high frequency,long duration and wide coverage in China.Timely and accurate assessment of drought can help to prepare for reducing and avoiding the losses caused by drought timely.However,drought as a complex phenomenon,only using drought index cannot fully reflect the severity of drought.Meanwhile,it is difficult to evaluate drought.The SMAPI drought index was calculated based on the distributed hydrological model,and daily sliding statistics method was used to realize the real-time evaluation of drought grade.Combined with land use data,the drought areas of different land uses were counted,and the duration of different drought grades was analyzed by area chart method.A real-time drought evaluation method considering drought index,land use,and drought duration was developed.The results of the drought evaluation in the study area show that the real-time drought evaluation results of this method are basically consistent with the quantitative results of historical drought,and can evaluate feature drought well in the region.