基于当日临界雨量的国家级地质灾害风险预警方法

A Risk Warning Method Based on the Intraday Critical Precipitation for National Geological Disaster

降水是引发滑坡、崩塌、泥石流的主要诱因。通过全国地质灾害易发程度区划研究,初步将全国划分为西北、东北、青藏高原、黄土高原、秦岭大巴山区、华北、云贵高原、中南和东南地区共9大预警分区。应用1950—2014年地质灾害历史灾情数据,选取灾害当天降水量作为建模因子,对其进行正态化处理后对地质灾害发生概率密度进行多项式、傅里叶和高斯拟合,发现高斯拟合方法最优,选取高斯拟合方法分区建立地质灾害概率预报方程,并结合业务地质灾害风险预警等级划分,制定地质灾害风险预警当日临界雨量阈值指标,应用2015年4—10月172个地质灾害样本以及江西兴国和于都2015年5月17—21日降水诱发地质灾害过程对当日临界雨量指标进行预报检验,结果表明当日临界雨量指标判别简单可行,判定效果较好,具有实际应用价值。

Landslides, debris-flows and collapses are caused by heavy precipitation frequently. A zonation for national geological disaster was carried out, and the 9 regions were divided so called as： the Northwestern China, Northeastern China, Tibetan Plateau, Loess Plateau, Qinba Mountain, Northern China, Yunnan-Guizhou Plateau, Central and South China and Southeastern China. The critically intraday precipitation for geological disaster in China was investigated based on the information of geological disasters in 1950-2014. Based on the Gaussian fitting method, the probability forecast model was adopted to describe probabilistic relation between precipitation and geological disaster. The intraday critical precipitation and forecast indexes of geological disaster were established with the geological disaster risk grades in business. And then this indexes were tested for 172 samples of geological disaster during April to October 2015 in China and samples of Xingguo and Yudu counies in Jiangxi Province during 17 May to 21 May 2015. The practical application has shown that the model has a good effect, the discriminant method of intraday critical precipitation indexes is effective and feasible.