summary: The Global Ensemble Forecast System (GEFS) is a weather forecast model made up of 21 separate forecasts, or ensemble members. The National Centers for Environmental Prediction (NCEP) started the GEFS to address the nature of uncertainty in weather observations, which are used to initialize weather forecast models. The proverbial butterfly flapping her wings can have a cascading effect leading to wind gusts thousands of miles away. This extreme example illustrates that tiny, unnoticeable differences between reality and what is actually measured can, over time, lead to noticeable differences between what a weather model forecast predicts and reality itself. The GEFS attempts to quantify the amount of uncertainty in a forecast by generating an ensemble of multiple forecasts, each minutely different, or perturbed, from the original observations. With global coverage, GEFS is produced four times a day with weather forecasts going out to 16 days and a 6 hour temporal resolution. This dataset has 1.0 degree horizontal resolution.
comment: Quantify the amount of uncertainty in mesoscale guidance by generating an ensemble of multiple forecasts, each minutely different, or perturbed, from the original observations.
funding: DOC/NOAA/NWS/NCEP/EMC > Environmental Modeling Center, National Centers for Environmental Prediction, National Weather Service, NOAA, U.S. Department of Commerce
rights: Electronic downloads of the data are free, however fees apply for data certification and distribution of the data on physical media. Fees vary based on order specifications.
abstract: The Global Ensemble Forecast System (GEFS) is a weather forecast model made up of 21 separate forecasts, or ensemble members. The National Centers for Environmental Prediction (NCEP) started the GEFS to address the nature of uncertainty in weather observations, which are used to initialize weather forecast models. The proverbial butterfly flapping her wings can have a cascading effect leading to wind gusts thousands of miles away. This extreme example illustrates that tiny, unnoticeable differences between reality and what is actually measured can, over time, lead to noticeable differences between what a weather model forecast predicts and reality itself. The GEFS attempts to quantify the amount of uncertainty in a forecast by generating an ensemble of multiple forecasts, each minutely different, or perturbed, from the original observations. With global coverage, GEFS is produced four times a day with weather forecasts going out to 16 days and a 6 hour temporal resolution.
Contributors:
Zoltar Toth (Scientific Contact)
Yuejian Zhu (Technical Contact)
Keywords:
GOVERNMENT AGENCIES-U.S. FEDERAL AGENCIES, DOC, NOAA, DOC/NOAA/NESDIS/NCEI,
National Centers for Environmental Information, NESDIS, U.S. Department of Commerce,
