摘要
[目的]识别气象变量在气候变化影响下出现的非平稳特征,揭示青海省气象干旱特征的时空演变规律,进而为青海省抗旱减灾提供一定的技术支持。[方法]基于GAMLSS模型构建以气候因子为解释变量的非平稳NSPEI,通过与传统SPEI对比遴选一种更适合青海省的气象干旱指数,并利用游程理论与Copula方法分析了不同情景下干旱重现期的分布特征。[结果]NSPEI较SPEI能更准确地识别青海省不同干旱程度,尤其对于较严重干旱事件。1961—2020年青海省干旱频率呈下降趋势且主要发生中度干旱和轻度干旱,干旱频率高发区为柴达木盆地西北部,青南牧区西南部为干旱低频区;干旱历时、干旱烈度分别以0.0189/a,0.0166/a的速率减小,两干旱特征时空变化较同步,均由西北向东北部递减。在中旱情景下,Tor平均为2.79 a一遇,Tand平均为7.52 a一遇;重旱Tor平均为4.11 a一遇,Tand平均为16.22 a一遇,青海省西南部是中、重旱高风险集中区,而东部农业区为重、中旱低风险集中区。[结论]青海省降水、气温序列的平稳性不复存在,考虑以气候因子为协变量NSPEI在揭示青海省时空变化趋势方面更有优势,可以用来预测未来青海省气象干旱的变化情况。
[Objective]The aims of this study are to identify the non-stationary characteristics of meteorological variables under the influence of climate change and reveal the spatiotemporal evolution law of meteorological drought characteristics in Qinghai Province,so as to provide some technical support for drought relief and disaster reduction in Qinghai Province.[Methods]Based on GAMLSS model,a non-stationary NSPEI with climatic factors as explanatory variables was constructed.A meteorological drought index more suitable for Qinghai Province was selected by comparing with the traditional SPEI,and the distribution characteristics of drought return periods under different scenarios were analyzed by using the run length theory and Copula method.[Results]Compared with SPEI,NSPEI could identify different drought degrees in Qinghai Province more accurately,especially for severe drought events.From 1961 to 2020,the drought frequency in Qinghai Province showed a decreasing trend and moderate and mild drought mainly occurred.The high drought frequency occurred in the northwest of Qaidam Basin and the low drought frequency area in the southwest of Qingnan pastoral area.Drought duration and drought intensity decreased at 0.0189/a and 0.0166/a,respectively.The spatiotemporal changes of the two drought characteristics were synchronous,and both decreased from northwest to northeast.In the moderate drought scenario,Tor and Tand averaged 2.79 and 7.52 years,respectively.The average Tor of severe drought was 4.11 years,and the average Tand was 16.22 years.The southwest of Qinghai Province was the high risk area of moderate and severe drought,while the eastern agricultural area was the heavy and low risk area of moderate and severe drought.[Conclusion]The stationarities of precipitation and temperature series in Qinghai Province no longer exist.Considering that NSPEI,which takes climate factor as covariable,has more advantages in revealing the spatiotemporal variation trend of Qinghai Province,it can be used to predict the future change of meteorological drought in Qinghai Province.
作者
孙媛
张鑫
闫彩
赵雪岩
雒舒琪
胡晓萌
Sun Yuan;Zhang Xin;Yan Cai;Zhao Xueyan;Luo Shuqi;Hu Xiaomeng(College of Water Resources and Architectural Engineering,Northwest A&F University,Yangling,Shaanxi 712100,China;Aishan Hydrologic Station,Shandong Hydrology and Water Resources Bureau,Yellow River Water Resources Commission,Liaocheng,Shandong 252200,China)
出处
《水土保持研究》
CSCD
北大核心
2023年第6期316-327,336,共13页
Research of Soil and Water Conservation
基金
陕西省科技统筹创新计划项目“现代农业节水技术模式与高效用水物联网系统基金”(2016KTZDNY-01-01)。
