Articles | Volume 15, issue 6
Research article
20 Dec 2019
Research article |  | 20 Dec 2019

Evaluation of nonidentical versus identical twin approaches for observation impact assessments: an ensemble-Kalman-filter-based ocean assimilation application for the Gulf of Mexico

Liuqian Yu, Katja Fennel, Bin Wang, Arnaud Laurent, Keith R. Thompson, and Lynn K. Shay

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Cited articles

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Short summary
We present a first direct comparison of nonidentical versus identical twin approaches for an ocean data assimilation system. We show that the identical twin approach overestimates the value of assimilating satellite observations and undervalues the benefit of assimilating temperature and salinity profiles. Misleading assessments such as undervaluing the impact of observational assets are problematic and can lead to misguided decisions on balancing investments among different observing assets.