《自然—氣候變化》上的一項研究預(yù)測,，考慮到未來氣候變暖的情況,，亞洲、非洲和南美洲部分地區(qū)的洪災(zāi)發(fā)生頻率將大幅提高,。但在全球某些地區(qū),，洪災(zāi)發(fā)生頻率可能反而降低。這表明有必要針對洪災(zāi)加劇采取一些應(yīng)對措施以及進一步引入一些策略來減緩溫室氣體排放,。
政府間氣候變化專業(yè)委員會（IPCC）最近的一項有關(guān)洪災(zāi)預(yù)測的特別報告稱,，由于“依據(jù)有限”，“總體來說，關(guān)于河流洪水變化的一些預(yù)測并沒有什么把握”,。事實上,，到目前為止，幾乎很少有研究采用了復(fù)雜模型來作出預(yù)測,，而且沒有科學(xué)家對未來變暖氣候中的洪災(zāi)風險進行過評估,。
Yukiko Hirabayashi等人根據(jù)11個氣候模型的輸入結(jié)果，呈現(xiàn)了本世紀末的全球洪災(zāi)發(fā)生風險,。他們研究了洪災(zāi)的變化并評價了其連貫性和范圍,。據(jù)研究小組預(yù)測，東南亞,、印度半島,、東非和安第斯山脈北部地區(qū)的洪災(zāi)發(fā)生頻率將增加。而在歐洲北部和東部,、安納托利亞,、中亞、北美洲中部和南美洲南部的許多地區(qū)洪災(zāi)發(fā)生頻率將降低,。
除了全球范圍的分析,，一些河流流域的出口也在模型中獲得分析。在21世紀內(nèi),，南亞,、東南亞、大洋洲,、非洲和亞歐大陸東北部的所有被研究到的河流的洪災(zāi)發(fā)生頻率將會是上升的,。研究人員還預(yù)測，在21世紀,，許多河流每10到50年便會發(fā)生一次百年一遇的洪水,。
研究人員警告，全球洪災(zāi)發(fā)生的增加依賴于氣候變暖的程度,，但洪災(zāi)發(fā)生的這種年度間變化可能意味著在氣候顯著變暖之前采取應(yīng)對措施的必要性,。他們強調(diào)，應(yīng)該重點關(guān)注低緯度國家的應(yīng)對和緩解措施,，因為預(yù)計這些國家的洪災(zāi)發(fā)生率和人口都將增加,。（生物谷Bioon.com）
生物谷推薦的英文摘要
Nature Climate Change DOI: doi:10.1038/nclimate1911
Global flood risk under climate change
Yukiko Hirabayashi,1 Roobavannan Mahendran,1 Sujan Koirala,1 Lisako Konoshima,1 Dai Yamazaki,2 Satoshi Watanabe,1 Hyungjun Kim3 & Shinjiro Kanae
A warmer climate would increase the risk of floods1. So far, only a few studies2, 3 have projected changes in floods on a global scale. None of these studies relied on multiple climate models. A few global studies4, 5 have started to estimate the exposure to flooding (population in potential inundation areas) as a proxy of risk, but none of them has estimated it in a warmer future climate. Here we present global flood risk for the end of this century based on the outputs of 11 climate models. A state-of-the-art global river routing model with an inundation scheme6 was employed to compute river discharge and inundation area. An ensemble of projections under a new high-concentration scenario7 demonstrates a large increase in flood frequency in Southeast Asia, Peninsular India, eastern Africa and the northern half of the Andes, with small uncertainty in the direction of change. In certain areas of the world, however, flood frequency is projected to decrease. Another larger ensemble of projections under four new concentration scenarios7 reveals that the global exposure to floods would increase depending on the degree of warming, but interannual variability of the exposure may imply the necessity of adaptation before significant warming.
