基于马尔可夫链的北京市546年来的旱涝演变特征

基于北京546年的旱涝资料,通过Mann-Kendall检验、滑动t检验等方法,分析得到不同旱涝变化趋势,并使用马尔可夫链研究了整体和每个趋势各状态间的转移概率以及重现期。研究表明北京地区旱涝灾害具有明显的趋势性,整体呈现"涝-旱-涝-旱"波动,局部有旱涝急转的现象。1470-1579年整体偏涝,转向偏涝年份的概率最高(31.3%);1580-1768年整体偏旱,转向正常年份的概率最高(34.3%),且容易发生多年连旱;1769-1898年整体偏涝,转向正常年份的概率最高(41.5%),且旱涝灾害发生概率基本相同;1899-1961年由涝转旱,转向偏旱年份的概率最高(35.1%);1962-2015年整体偏旱,转向偏旱概率最高(29.7%),且容易发生多年连旱。对546年旱涝整体分析,旱涝转移趋向于正常,但整体处于一个偏旱的状态。

Analysis on evolution of droughts and floods in Beijing over the last 546 years based on Markov chain

Based on the data of dro ug hts and flo ods o ver the last 546 y ea rs in Beijing, we o btained different trends o f flo ods and dr oughts using Mann2Kendall test and mo ving t2test, and w e used Mar ko v chain to study the t ransfer pr obabilit y and recurrence of different states in each tr end. T he st udy show ed that the dro ug ht and flo od disasters in Beijing manifested o bv ious tenden2 cies. The over all trend was " f loo d2dro ug ht2flo od2dr ought " fluctuatio n, w ith rapid shifts betw een dro ug ht and floo d at some times. During 147021579, Beijing was pr one to f loo d and had the highest pro bability of t ransferring to a part ial floo d year ( 311 3% ) . During 158021768, Beijing w as pro ne to dr ought and had the highest probability o f transferring to a no rmal year ( 341 3% ) ; it w as also v ery likely to hav e co ntinuous dr oughts. During 176921898, Beijing w as pr one to floo d and had the hig hest pr obability o f t ransferring a normal year ( 411 5% ) ; t he occurrence pro babilities of droug ht and flo od disasters wer e basically the same. During 189921961, Beijing t ransf erred fr om flo od to droug ht and had the highest pr obability of transferring to a partial dr ought y ear ( 351 1% ) . During 196222015, Beijing w as pro ne to droug ht , and had the hig hest probability of tr ansferring to a partial dr ought y ea r ( 291 7% ) ; it w as also v ery likely to have continuo us dr oughts. The ov erall ana lysis of 546 years o f dro ug hts # 2 and flo ods show ed that the tr ansfer o f dr oughts and floo ds tended to be no rmal, but the o verall situation was partial dro ug ht.