A conditional stochastic weather generator for seasonal to multi-decadal simulations

JOURNAL OF HYDROLOGY

卷:556

Article

Verdin, Andrew¹  Rajagopalan, Balaji^1,2  Kleiber, William³  Podesta, Guillermo⁴  Bert, Federico⁵ 

[1] Univ Colorado, Dept Civil Environm & Architectural Engn, Boulder, CO 80309 USA

[2] Univ Colorado, Cooperat Inst Res Environm Sci, Boulder, CO 80309 USA

[3] Univ Colorado, Dept Appl Math, Boulder, CO 80309 USA

[4] Univ Miami, Sch Marine & Atmospher Sci, Miami, FL USA

[5] Univ Buenos Aires, CONICET, Fac Agron, Buenos Aires, DF, Argentina

关键词: Generalized linear models;    Stochastic weather generator;    Conditional simulation;    Downscaling seasonal forecasts;    Daily precipitation;    Daily temperature;   

DOI  :  10.1016/j.jhydrol.2015.12.036

来源: Elsevier

【 摘 要 】

We present the application of a parametric stochastic weather generator within a nonstationary context, enabling simulations of weather sequences conditioned on interannual and multi-decadal trends. The generalized linear model framework of the weather generator allows any number of covariates to be included, such as large-scale climate indices, local climate information, seasonal precipitation and temperature, among others. Here we focus on the Salado A basin of the Argentine Pampas as a case study, but the methodology is portable to any region. We include domain-averaged (e.g., areal) seasonal total precipitation and mean maximum and minimum temperatures as covariates for conditional simulation. Areal covariates are motivated by a principal component analysis that indicates the seasonal spatial average is the dominant mode of variability across the domain. We find this modification to be effective in capturing the nonstationarity prevalent in interseasonal precipitation and temperature data. We further illustrate the ability of this weather generator to act as a spatiotemporal downscaler of seasonal forecasts and multidecadal projections, both of which are generally of coarse resolution. (C) 2015 Elsevier B.V. All rights reserved.

【 授权许可】

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