AUTHOR=Penny Stephen G. , Akella Santha , Balmaseda Magdalena A. , Browne Philip , Carton James A. , Chevallier Matthieu , Counillon Francois , Domingues Catia , Frolov Sergey , Heimbach Patrick , Hogan Patrick , Hoteit Ibrahim , Iovino Doroteaciro , Laloyaux Patrick , Martin Matthew J. , Masina Simona , Moore Andrew M. , de Rosnay Patricia , Schepers Dinand , Sloyan Bernadette M. , Storto Andrea , Subramanian Aneesh , Nam SungHyun , Vitart Frederic , Yang Chunxue , Fujii Yosuke , Zuo Hao , O’Kane Terry , Sandery Paul , Moore Thomas , Chapman Christopher C. TITLE=Observational Needs for Improving Ocean and Coupled Reanalysis, S2S Prediction, and Decadal Prediction JOURNAL=Frontiers in Marine Science VOLUME=6 YEAR=2019 URL=https://www.frontiersin.org/journals/marine-science/articles/10.3389/fmars.2019.00391 DOI=10.3389/fmars.2019.00391 ISSN=2296-7745 ABSTRACT=

Developments in observing system technologies and ocean data assimilation (DA) are symbiotic. New observation types lead to new DA methods and new DA methods, such as coupled DA, can change the value of existing observations or indicate where new observations can have greater utility for monitoring and prediction. Practitioners of DA are encouraged to make better use of observations that are already available, for example, taking advantage of strongly coupled DA so that ocean observations can be used to improve atmospheric analyses and vice versa. Ocean reanalyses are useful for the analysis of climate as well as the initialization of operational long-range prediction models. There are many remaining challenges for ocean reanalyses due to biases and abrupt changes in the ocean-observing system throughout its history, the presence of biases and drifts in models, and the simplifying assumptions made in DA solution methods. From a governance point of view, more support is needed to bring the ocean-observing and DA communities together. For prediction applications, there is wide agreement that protocols are needed for rapid communication of ocean-observing data on numerical weather prediction (NWP) timescales. There is potential for new observation types to enhance the observing system by supporting prediction on multiple timescales, ranging from the typical timescale of NWP, covering hours to weeks, out to multiple decades. Better communication between DA and observation communities is encouraged in order to allow operational prediction centers the ability to provide guidance for the design of a sustained and adaptive observing network.