气候变化背景下区域不同类型干旱转化机制及其预估研究-以山东省为例

Under the background of global climate change, the occurrence of drought has enhanced in scope, frequency and intensity, and brings great damage to the social and economic development. Studies on drought evolution mechanism and future situation prediction get more and more attentions from not only academic community but also government departments..Shandong province, divided by three important basins,Yellow River basin, Huaihe basin and Haihe basin, is a region that pretty frequent in drought. In this context we select Shandong Province as the research area and present this project aim to explain the scientific questions as following. （1）On the basis of the long term hydro-meteorological data from 1961 to 2013 and selecting suitable evaluation index, the change characteristics and of meteorological drought, hydrological drought and agricultural drought are investigated systematically in the past 50 years. The corresponding influence factors of different droughts are further analyzed. （2）Selecting large-scale land surface model VIC, the distributed regional hydrological model of Shandong province is established firstly. Based on the key key hydrological data outputed from the model, some methods including Bayesian Methods and so on are applied to reveal the internal relations and transformation mechanism of different types of drought. （3）Coupled with the reginoal climate model RegCM4.0 developed by new generation of scenarions of greenhouse gas emission, the successful hydrological model output hydro-meteorological data under different representative concentration pathways of RCP4.5 and RCP8.5 from 2015 to 2050. By means of this, the evolution trends of different types of droughts in Shandong Province are predicted, and their uncertainty is further explored by Monte Carlo method ..The outstanding innovation of this project is that we investigate the transformation mechanism of drought from a perpective of composite factors, and predict the drought evolution trend by means of coupling the hydrological model and new regional climate model with high resolution.We believe the result of this research is essential not only for in-depth understanding the drought evolution rule in the provencial region under the impact of climate change, but also for developing disaster reduction measures, aaccomplishing sustainable utilization of water resources in Shandong Province.

气候变化背景下，干旱发生的范围、频率和强度显著增强，干旱机制及未来形势预估研究受普遍重视和关注。本项目以横跨黄淮海三大流域同时干旱频发的山东省为研究区，基于1961-2013年实测气象、水文等资料，选择合适的干旱评价指标，系统分析近50年来山东省气象干旱、水文干旱以及农业干旱的时空变化特征及其影响因素。以VIC大尺度陆面水文模型为基础，通过构建以行政区域为边界的山东省分布式水文模型，结合贝叶斯分析等方法，揭示不同类型干旱的内在联系和转化机制。在此基础上，耦合RCPs新情景下RegCM4.0区域气候模式，预估不同典型浓度路径下（RCP4.5、RCP8.5）山东省2015-2050年干旱发展趋势，并采用蒙特卡罗法进行预测结果的不确定性分析。研究结果对深入理解和认识气候变化背景下区域干旱的演变规律具有重要的意义，同时可为区域制定抗旱减灾对策、实现水资源可持续利用提供科学依据。

气候变化背景下，干旱发生的范围、频率和强度显著增强，干旱机制及未来形势预估研究受到普遍重视和关注。本项目选择山东省为研究区域，重点开展了近55年山东省不同类型（气象干旱、水文干旱、农业干旱）干旱时空演变特征及影响因素分析、不同类型干旱转化机制分析、RCPs新情景下未来干旱演化趋势预估等三方面的研究。主要结论如下：（1）近55年来，山东省干旱在时间序列上呈现缓慢加重趋势，干旱主要发生在鲁西、鲁北和山东半岛北部部分地区。山东省干旱与降水均存在明显的周期变化规律，并且二者的规律存在很大的正相关性，说明主要受降水因素影响，但地形、作物结构等也是重要因素。（2）在干旱次数和干旱面积上，山东省气象干旱比水文干旱和农业干旱突出，内部机制是气象干旱重点受降水因素影响，而农业干旱和水文干旱则还与土壤含水量、水资源量等因素密切相关，有滞后性。三种干旱在历时指标上呈现明显的正相关性，在面积指标上则相关性较弱，并且不同区域不同时段存在明显差别，主要是人类活动调剂的影响。（3）RCP4.5和RCP8.5典型浓度路径下，未来（2020-2050年）山东省干旱具有加重趋势，严重程度比历史时期高。特别是在21世纪30年代和40年代，干旱密集程度更严重。干旱仍发生在鲁西、鲁北和山东半岛北部，这些地区需要提前做好充分的抗旱准备。研究结果对深入理解和认识气候变化背景下区域干旱演变规律具有重要意义，同时可为制定抗旱减灾对策、实现水资源可持续利用提供科学依据。