Forcing Hydrologic Models with GCM Output: Bias Correction vs. the "Delta Change" Method
Forcing Hydrologic Models with GCM Output: Bias Correction vs. the "Delta Change" Method
复制标题
使用 GCM 输出强制水文模型：偏差校正与“Delta 变化”方法
DOI：
10.1061/9780784413548.214
复制
发表时间：
2014
期刊：
影响因子：
--
通讯作者：
P. Spellman
中科院分区：
文献类型：
--
作者：
K. LaFond;V. Griffis;P. Spellman
据预测，全球气候变化将对洪水事件的频率和严重程度产生影响。水文模型可用于更深入地了解未来气候条件下的洪水风险。在这项研究中，输出从几个全球环流模式（GCM）的一系列可能的未来气候情景被用来迫使水文模型的案例研究流域建立使用土壤和水评估工具（SWAT）。GCM的输出来自世界气候研究计划（WCRP）的耦合模式相互比较项目第三阶段（CMIP 3）多模式数据集。在分水岭尺度上，使用“增量变化”方法或偏差校正来应用输出。本研究比较了两种不同的GCM输出调整方法在SWAT模型输出和相关洪水风险预测中的差异。初步结果表明，三角洲变化的方法是更有用的模拟极端事件时，因为它更好地保存每日的气候变率，而不是使用偏差校正的GCM输出。三角洲变化的方法似乎产生的洪水风险的估计是更现实的比那些使用GCM输出偏差校正。
Global climate change is predicted to have impacts on the frequency and severity of flood events. Hydrologic modeling can be used to gain a deeper understanding of the flood risk projected under future climatic conditions. In this study, output from several Global Circulation Models (GCMs) for a range of possible future climate scenarios was used to force a hydrologic model for a case study watershed built using the Soil and Water Assessment Tool (SWAT). GCM output was obtained from the World Climate Research Programme's (WCRP's) Coupled Model Intercomparison Project phase 3 (CMIP3) multi-model dataset. At the watershed scale, the output was applied with either the “delta change” method or a bias correction. This research compares the differences in SWAT model outputs and associated flood risk projections when using the two different methods of adjusting GCM output. Preliminary results indicate that the delta change method is more useful when simulating extreme events as it better preserves daily climate variability as opposed to using bias corrected GCM output. The delta change method appears to produce estimates of flood risk that are more realistic than those obtained using GCM output with a bias correction.