21DroughtdisasterinvestigationandriskassessmXXXX-XX-XX發(fā)布I 2 3 6 9 本文件按照GB/T1.1—2020《標(biāo)準(zhǔn)化工作導(dǎo)則第1部分：標(biāo)準(zhǔn)化文件的結(jié)構(gòu)和起草規(guī)則》的規(guī)定起本文件主要起草人：劉鳴彥，趙春雨，周曉宇，崔妍，李經(jīng)緯，侯依玲，李明倩，敖1干旱災(zāi)害調(diào)查與風(fēng)險(xiǎn)評(píng)估方法GB/T20481-2017氣象干旱QX/T597-2021區(qū)域性干旱過程監(jiān)某時(shí)間段內(nèi)由于天氣氣候異常引起的地表水分短缺的2干旱災(zāi)害承災(zāi)體暴露度droughtdisa干旱災(zāi)害承災(zāi)體脆弱性droughtdisastervu干旱災(zāi)害發(fā)生的可能性及其造成的損失或不利4干旱災(zāi)害調(diào)查4.1.1氣象觀測(cè)數(shù)據(jù)4.1.2災(zāi)情數(shù)據(jù)4.1.3承災(zāi)體數(shù)據(jù)區(qū)域總?cè)丝?、?guó)民生產(chǎn)總值（GDP）、農(nóng)作物4.1.4基礎(chǔ)地理信息），4.2干旱過程識(shí)別4.2.1氣象干旱指數(shù)的選取4.2.2干旱過程客觀識(shí)別方法干旱過程識(shí)別以MCI為基礎(chǔ)指標(biāo)，依據(jù)《區(qū)域4.3干旱災(zāi)害調(diào)查內(nèi)容4.3.1歷次干旱過程致災(zāi)危險(xiǎn)性調(diào)查3對(duì)濕潤(rùn)度指數(shù)、受干旱災(zāi)害影響的承災(zāi)體（人口、經(jīng)濟(jì)、農(nóng)作物）數(shù)量和價(jià)值量的調(diào)查。4.3.2年度干旱致災(zāi)危險(xiǎn)性調(diào)查5.1干旱危險(xiǎn)性評(píng)估基于30年以上的歷史序列，優(yōu)選擬合分布函數(shù)（附錄B），計(jì)算度閾值，通過權(quán)重求和的方法得到干旱危險(xiǎn)性評(píng)估指數(shù)，按公式（1）計(jì)H——干旱危險(xiǎn)性評(píng)估指數(shù)；43214注：為區(qū)域H的算術(shù)平均值，δ為區(qū)域H的標(biāo)準(zhǔn)差5.2干旱災(zāi)害風(fēng)險(xiǎn)評(píng)估···················································將致災(zāi)危險(xiǎn)性、承災(zāi)體暴露度和承災(zāi)體脆弱性各指標(biāo)進(jìn)行歸一化（附錄），RI=Hw?×Ewe×Vwv·································································(3)基于干旱災(zāi)害風(fēng)險(xiǎn)評(píng)估指數(shù)RI，根據(jù)研究范圍，按照距標(biāo)準(zhǔn)差的倍數(shù)進(jìn)行等·················································xi——干旱風(fēng)險(xiǎn)評(píng)估指數(shù)值;——干旱風(fēng)險(xiǎn)評(píng)估指數(shù)值的區(qū)域平均值;標(biāo)準(zhǔn)參考等級(jí)劃分見表2，分為五級(jí)：低、較低、中、較高、高554321α≤-2-2<α≤-1-1<α≤11<α≤2α>26個(gè)次次次次次7%℃日天天天天天8次次次次次9俗稱n年一遇。重現(xiàn)期的計(jì)算方法一般以現(xiàn)有觀測(cè)數(shù)據(jù)為基礎(chǔ)，使用數(shù)理統(tǒng)計(jì)方法，用某種分布方式來α?1e?β····································································································································································································································P(x)=P(x≥x)=1?e?e?a(x?b)····················································(B.7)式中：a是尺度參數(shù)，b是分布密度的眾?0.5772×Sx·········2/2δ····················································1lnXi···················································2···································比重pij：pij=···················································x’=0.5+0.5×(x?xmin)?(xmax?xmin)·························