Main regional climate modelling development at AEMET using HCLIM

Several studies have shown the added value of convection-permitting climate modelling, in particular regarding extreme events, including heat waves and high precipitation events (Lind et al., 2020, Fosser et al., 2024). HCLIM consortium develops a high resolution climate model, with a non-hydrostatic version using AROME physics. Current evaluation has shown that HCLIM is a robust tool able to add value when reproducing the behaviour of the climate system over complex areas (Belusic et al., 2020).

AEMET has been a member of HCLIM since its foundation and has participated in the effort to develop the model and provide a complete and adaptable tool. In particular, we present some results on the contributions from AEMET: as many basin resources depend significantly on groundwater, works focused on improving the surface component with a new watertable parametrization. On the other hand, AEMET has contributed actively to the development of a more detailed aerosol scheme. An active line of development is currently underway, focused on the development of a fully ocean-coupled model.

Future plans include the generation of high resolution climate simulations over Spain, assessing the added value of the model and exploring different strategies for the generation of high resolution climate scenarios feeding National Adaptation Plan. Some preliminary results, evaluating the added value against CORDEX simulations, are shown. Additionally, several tests comparing different strategies regarding model configuration and the impact of the domain size and nesting strategy have been conducted, giving insight into designing the strategy for the generation of an ensemble of simulations.

References:

Belušić, Danijel & de Vries, Hylke & Dobler, A. & Landgren, Oskar & Lind, Petter & Lindstedt, David & Pedersen, Rasmus & Sánchez-Perrino, Juan & Médus, Erika & Ulft, Bert & Wang, Fuxing & Andrae, Ulf & Batrak, Yurii & Kjellström, Erik & Lenderink, Geert & Nikulin, Grigory & Pietikäinen, Joni-Pekka & Rodriguez-Camino, Ernesto & Samuelsson, Patrick & Wu, Minchao. (2020). HCLIM38: a flexible regional climate model applicable for different climate zones from coarse to convection-permitting scales. Geoscientific Model Development. 13. 1311-1333. 10.5194/gmd-13-1311-2020. http://dx.doi.org/10.5194/gmd-13-1311-2020

Fosser, G., Gaetani, M., Kendon, E.J. et al. Convection-permitting climate models offer more certain extreme rainfall projections. npj Clim Atmos Sci 7, 51 (2024). https://doi.org/10.1038/s41612-024-00600-w

Lind, P., Belušić, D., Christensen, O.B. et al. Benefits and added value of convection-permitting climate modeling over Fenno-Scandinavia. Clim Dyn 55, 1893–1912 (2020). https://doi.org/10.1007/s00382-020-05359-3