Articles | Volume 15, issue 24
https://doi.org/10.5194/gmd-15-9057-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/gmd-15-9057-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
An ensemble Kalman filter-based ocean data assimilation system improved by adaptive observation error inflation (AOEI)
RIKEN Center for Computational Science, Kobe, 6500047, Japan
RIKEN Cluster for Pioneering Research, Kobe, 6500047, Japan
RIKEN Interdisciplinary Theoretical and Mathematical Sciences Program (iTHEMS), Kobe, 6500047, Japan
Institute for Space-Earth Environmental Research, Nagoya University, Nagoya, 4648601, Japan
Takemasa Miyoshi
CORRESPONDING AUTHOR
RIKEN Center for Computational Science, Kobe, 6500047, Japan
RIKEN Cluster for Pioneering Research, Kobe, 6500047, Japan
RIKEN Interdisciplinary Theoretical and Mathematical Sciences Program (iTHEMS), Kobe, 6500047, Japan
Misako Kachi
Earth Observation Research Center, Japan Aerospace Exploration Agency, Tsukuba, 3058505, Japan
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Effective use of observations with numerical weather prediction models, also known as data assimilation, is a key part of weather forecasting systems. For precise prediction at the scales of thunderstorms, fast nonlinear processes pose a grand challenge because most data assimilation systems are based on linear processes and normal distribution errors. We investigate how, every 30 s, weather radar observations can help reduce the effect of nonlinear processes and nonnormal distributions.
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Short summary
An adaptive observation error inflation (AOEI) method was proposed for atmospheric data assimilation to mitigate erroneous analysis updates caused by large observation-minus-forecast differences for satellite brightness temperature around clear- and cloudy-sky boundaries. This study implemented the AOEI with an ocean data assimilation system, leading to an improvement of analysis accuracy and dynamical balance around the frontal regions with large meridional temperature differences.
An adaptive observation error inflation (AOEI) method was proposed for atmospheric data...