气候变化领域集成服务门户(CCPortal): Subseasonal-to-Seasonal Hindcast Skill Assessment of Ridging Events Related to Drought Over the Western United States

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DOI	10.1029/2020JD033655
	Subseasonal-to-Seasonal Hindcast Skill Assessment of Ridging Events Related to Drought Over the Western United States
	Gibson P.B.; Waliser D.E.; Goodman A.; DeFlorio M.J.; Delle Monache L.; Molod A.
发表日期	2020
ISSN	2169897X
卷号	125 期号:22
英文摘要	Persistent atmospheric ridging events centered near the western United States are associated with widespread precipitation deficits and meteorological drought. Due to the relatively low skill of dynamical models in forecasting precipitation on subseasonal-to-seasonal (S2S) time scales across this region, forecasts of ridging are explored in this study as a potential bridge for early warning drought prediction. To assess skill, we evaluate deterministic and probabilistic S2S hindcasts (out to 6 week lead time) of ridging events and geopotential height anomalies over the western United States in five ensemble hindcast systems. Prediction skill for ridging events is shown to be highly variable across models. For some models, longer-time-averaged patterns of geopotential height anomalies across the first 6 weeks can be skillfully simulated, when evaluated probabilistically against climatology. The most skillful models show modest skill in forecasting above normal ridging occurrences at lead times of Weeks 3–4 and Weeks 5–6, with some sensitivity to the specific ridge location and method for determining skill. Using the European Centre for Medium-Range Weather Forecasts (ECMWF) model as a case study, longer lead time forecast busts are shown to often occur under extended periods of highly active La Nina-like tropical convection. Model errors at simulating these tropical convection features may have a disproportionately large impact and degrade downstream forecasts over the western United States. Despite the documented model shortcomings, our results highlight an opportunity to target skillful ridging forecasts from dynamical models for improving early warning drought forecasting at S2S lead times. ©2020. American Geophysical Union. All Rights Reserved.
英文关键词	atmospheric ridging; forecast skill; precipitation; S2S; water resource management
语种	英语
来源期刊	Journal of Geophysical Research: Atmospheres
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/185652
作者单位	Center for Western Weather and Water Extremes, Scripps Institution of Oceanography, University of California, San Diego, La Jolla, CA, United States; Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, United States; Global Modeling and Assimilation Office, NASA Goddard Space Flight Center, Greenbelt, MD, United States
推荐引用方式 GB/T 7714	Gibson P.B.,Waliser D.E.,Goodman A.,et al. Subseasonal-to-Seasonal Hindcast Skill Assessment of Ridging Events Related to Drought Over the Western United States[J],2020,125(22).
APA	Gibson P.B.,Waliser D.E.,Goodman A.,DeFlorio M.J.,Delle Monache L.,&Molod A..(2020).Subseasonal-to-Seasonal Hindcast Skill Assessment of Ridging Events Related to Drought Over the Western United States.Journal of Geophysical Research: Atmospheres,125(22).
MLA	Gibson P.B.,et al."Subseasonal-to-Seasonal Hindcast Skill Assessment of Ridging Events Related to Drought Over the Western United States".Journal of Geophysical Research: Atmospheres 125.22(2020).