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Is One Forecast Model Better Than Another?

Is One Forecast Model Better Than Another?

Blog post contributed by: Tim DelSole* The Sign Test Is one forecast model better than another? A natural approach to answering this question is to run a set of forecasts with each model and then see which set has more skill. This comparison requires a statistical test to ensure that the estimated difference represents a real difference in skill, rather than a random sampling error. Unfortunately, there are three problems with using standard difference tests: they have low statistical power,…

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Hydrological forecasting, ensembles and related topics at AGU 2018: Time to write your abstracts

Hydrological forecasting, ensembles and related topics at AGU 2018: Time to write your abstracts

Contributed by Andy Wood and Flavio Lehner, NCAR  You can help to advance the science of hydrological prediction, forecasting systems, and our understanding of the value of ensembles through the presentation of your recent related scientific and practical developments, applications and approaches at the AGU Fall Meeting in 2018.  The meeting will be held on December 10-14, 2018. Why should I go to AGU next year? For once, AGU will be held in Washington D.C. instead of San Francisco. This is…

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Drought Monitoring and Prediction in South Asia

Drought Monitoring and Prediction in South Asia

Contributed by:  Vimal Mishra* and Saran Aadhar, Civil Engineering, Indian Institute of Technology (IIT) Gandhinagar, India Drought is one of the most complex natural disasters. In South Asia — a region including India, Pakistan, Bangladesh, Sri Lanka, Nepal, and Bhutan — increasing population, dependence on agriculture, and frequent droughts have resulted in water scarcity and food scarcity. In India, for example, about 330 million people were affected by the 2014-15 droughts, which led to severe water shortages (Mishra et al., 2016)….

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Using ensemble forecasts to inform risk-based operations of a reservoir in Northern California

Using ensemble forecasts to inform risk-based operations of a reservoir in Northern California

Contributed by:  Chris Delaney, Sonoma County Water Agency; John Mendoza, Sonoma County Water Agency; Brett Whitin, California Nevada River Forecast Center; Rob Hartman, Consultant Lake Mendocino is a reservoir located in Mendocino County, California, about 110 miles north of the City of San Francisco. This small 144 million cubic meter reservoir (Figure 1) releases water into the Russian River and provides both flood protection and water supply to downstream communities. Lake Mendocino is cooperatively managed by 2 government offices: the…

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Hydrologic similarity: Bridging the gap between hyper-resolution and hydrologic ensemble prediction

Hydrologic similarity: Bridging the gap between hyper-resolution and hydrologic ensemble prediction

Contributed by:  Nate Chaney (Princeton University) and Andy Newman (NCAR) The ever-increasing volume of global environmental data and the continual increase in computational power continue to drive a push towards fully distributed modeling of the hydrologic cycle at hyper-resolutions (10-100 meters) [Wood et al., 2011]. In principle, this has the potential to increase model fidelity and lead to more locally-relevant hydrologic predictions (e.g., soil moisture at the farm level). However, for the foreseeable future, due to computational constraints this modeling…

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