First results and future plans for ecRad radiation in Météo-France models
- 1Centre National de Recherches Météorologiques (Météo-France, CNRS), Toulouse, France (sophia.schaefer@meteo.fr)
- 2European Centre for Medium-Range Weather Forecasts, Reading, UK
- 3University of Reading, Reading, UK
- 4University of Oxford, Oxford, UK
- 5Danish Meteorological Institute, Copenhagen, Denmark
Radiation in the atmosphere provides the energy that drives atmospheric dynamics and physics on all scales, from cloud particle growth to global weather and climate. Radiation schemes in global weather and climate models have to simplify the complex interaction of radiation with the Earth system. Capturing the interactions of gases and clouds with radiation is particularly challenging, since gas effects are extremely wavelength-dependent, while clouds vary strongly on small spatial and temporal scales, and they both interact strongly with radiation. Uncertainties in the radiation scheme and the cloud, aerosol and gas and inputs lead to uncertainties in weather and climate processes, such as energy balance, cloud development and dynamics.
The radiation scheme ecRad (Hogan & Bozzo 2018) has been operational in the IFS model at ECMWF since 2017 and in ICON at Deutscher Wetterdienst (DWD) since 2021 and will be the next radiation scheme in the operational numerical weather prediction models AROME and ARPEGE, the climate model ARPEGE-Climat and the regional research model Méso-NH at Météo-France. As a modular scheme, ecRad provides the opportunity to vary parametrisations and assumptions individually. Several options are available for the radiation solver, cloud vertical overlap and horizontal inhomogeneity treatment and cloud hydrometeor optical property parametrisations. The solver SPARTACUS is the only radiation solver in a global model that can treat 3D radiative effects. The new gas optics model ecCKD can improve both precision and cost of the gas optics calculation, as can recent code optimisations.
We will present the status of and future plans for implementation in the Météo-France models, and show first evaluation results for radiation, energy balance and clouds on various scales scales. We will also investigate the impact of cloud and aerosol input and search for the best settings for radiation balance, model energy and physics and forecast performance. Finally, we will present future plans for radiation work in the Météo-France models.
Reference:
Hogan, R. J., & Bozzo, A. (2018), A flexible and efficient radiation scheme for the ECMWF model. Journal of Advances in Modeling Earth Systems, 10, 1990-2008. https://doi.org/10.1029/2018MS001364
How to cite: Schäfer, S., Hogan, R., Rodier, Q., Libois, Q., Seity, Y., Roehrig, R., and Ukkonen, P.: First results and future plans for ecRad radiation in Météo-France models, EMS Annual Meeting 2024, Barcelona, Spain, 1–6 Sep 2024, EMS2024-172, https://doi.org/10.5194/ems2024-172, 2024.
