Articles | Volume 26, issue 11
https://doi.org/10.5194/nhess-26-5769-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/nhess-26-5769-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
The operational 3DEnVar data assimilation scheme for the Météo-France convective scale model AROME-France
Pierre Brousseau
CORRESPONDING AUTHOR
CNRM/GMAP, Université de Toulouse, Météo-France, CNRS, Toulouse, France
Valérie Vogt
CNRM/GMAP, Université de Toulouse, Météo-France, CNRS, Toulouse, France
Etienne Arbogast
CNRM/GMAP, Université de Toulouse, Météo-France, CNRS, Toulouse, France
Maud Martet
CNRM/GMAP, Université de Toulouse, Météo-France, CNRS, Toulouse, France
Guillaume Thomas
CNRM/GMAP, Université de Toulouse, Météo-France, CNRS, Toulouse, France
Loïk Berre
CNRM/GMAP, Université de Toulouse, Météo-France, CNRS, Toulouse, France
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Pauline Combarnous, Felix Erdmann, Olivier Caumont, Éric Defer, and Maud Martet
Nat. Hazards Earth Syst. Sci., 22, 2943–2962, https://doi.org/10.5194/nhess-22-2943-2022, https://doi.org/10.5194/nhess-22-2943-2022, 2022
Short summary
Short summary
The objective of this study is to prepare the assimilation of satellite lightning data in the French regional numerical weather prediction system. The assimilation of lightning data requires an observation operator, based on empirical relationships between the lightning observations and a set of proxies derived from the numerical weather prediction system variables. We fit machine learning regression models to our data to yield those relationships and to investigate the best proxy for lightning.
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Short summary
Since October 2024, the Météo-France operational convective scale model AROME-France uses a three-dimensional ensemble-based variational data assimilation system. This allows observations to be spatialised in a flow-dependent way, leading to improved initial conditions. Numerous sensitivity studies allowed to configure this scheme in an operational context. Major positive impacts on the forecast quality have been demonstrated over a long period and on several severe meteorological situations.
Since October 2024, the Météo-France operational convective scale model AROME-France uses a...
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