Gridded Ensemble Precipitation and Temperature Estimates over the Contiguous United States Version 2.0

Generally uncertainty is not explicitly accounted for in gridded products of precipitation or temperature; if it is represented, it is often included in an ad-hoc manner. A lack of quantitative uncertainty estimates for hydrometeorological forcing fields limits the application of advanced data assimilation systems and other analysis tools in land-surface and hydrologic modeling.

This study develops a gridded, observation-based ensemble of precipitation and temperature at a daily increment for the period 1980-2012. This allows for the estimation of precipitation and temperature uncertainty in hydrologic modeling and data assimilation through the use of the ensemble variance. Statistical verification of the ensemble indicates that it has generally good reliability and discrimination of events of various magnitudes, but has a slight wet bias for high threshold events (greater than 50 mm).