"The goal of retrospective data assimilation or 'reanalysis' is to combine disparate observations into physically consistent estimates of the past state of the Earth system and its components - e.g., ocean, atmosphere, waves, land, cryosphere, and ionosphere - with quantified uncertainties. Reanalyses spanning the limits of the instrumental record of each component serve as a key tool for climate monitoring and analysis, and for providing initial and boundary conditions and verification for retrospective forecasts. The reanalysis research enterprise, begun nearly 40 years ago, has led to a cycle of improvement of models, data assimilation systems, and historical observational databases required for improved reanalysis datasets. Together, these improvements have led to dramatic advances in understanding and predicting weather and climate variability, from extreme events to centennial trends. The National Oceanic and Atmospheric Administration (NOAA), which has a need to provide prediction capabilities at lead times from minutes to decades, continues to be an important contributor in the progress towards the goal of improved Earth system reanalysis"--Page 4. [doi:10.7289/V53J39ZZ (http://dx.doi.org/10.7289/V53J39ZZ)]

http://doi.org/10.7289/V53J39ZZ

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