The CORDEX.be initiative as a foundation for climate services in Belgium

The CORDEX.be project created the foundations for Belgian climate services by producing high-resolution Belgian climate information that (a) incorporates the expertise of the different Belgian climate modeling groups and that (b) is consistent with the outcomes of the international CORDEX ("COordinated Regional Climate Downscaling Experiment") project. The key practical tasks for the project were the coordination of activities among different Belgian climate groups, fostering the links to specific international initiatives and the creation of a stakeholder dialogue. Scientifically, the CORDEX.be project contributed to the EURO-CORDEX project, created a small ensemble of High-Resolution (H-Res) future projections over Belgium at convection-permitting resolutions and coupled these to seven Local Impact Models. Several impact studies have been carried out. The project also addressed some aspects of climate change uncertainties. The interactions and feedback from the stakeholder dialogue led to different practical applications at the Belgian national level

Model state and parameter estimation by assimilation of temperature profiles with an ensemble Kalman filter in North Sea applications

Coastal management and maritime safety strongly rely on accurate representations of the sea state. Both dynamical models and observations provide abundant pieces of information. However, none of them provides the complete picture. The assimilation of data into models is one way to improve our knowledge of the ocean state. Its application in coastal models remains challenging because of the wide range of temporal and spatial variabilities of the processes. This dissertation investigates the assimilation of temperature profiles with an ensemble Kalman filter in 1-D and 3-D North Sea simulations. Two approaches of data assimilation are considered: model state estimation and combined model state and parameter estimation. In model state estimation, adequate parameters for model error sampling are first determined using a square root algorithm that assumes observations to be perfect. Then, a similar but more realistic algorithm able to account for observations' errors (low rank square root algorithm) is applied. A detailed assessment of the benefit of data assimilation on temperature is carried out, including a comparison against independent observations. For combined model state and parameter estimation the low rank square root algorithm is applied to a set of model parameters primarily involved in the representation of the temperature of the upper mixed layer. They are the optical attenuation and the surface heat exchange coefficients. Moreover, the spatial variability of the parameters' estimation is examined at two stations typical of the hydrodynamical regimes of the North Sea in summer.(PHYS 3) -- UCL, 201

Combining regional downscaling expertise in Belgium: CORDEX and beyond

The main objectives of the CORDEX.be project were: 1. Contribute to the international climate community by participating to EURO-CORDEX by performing regional climate simulations over Europe. 2. Provide an ensemble of High-Resolution (H-Res) climate simulations over Belgium i.e. to create a small ensemble of high-resolution future projections over Belgium at convectionpermitting resolutions. 3. Couple these model simulations to seven local-impact models for impact studies. 4. Present an overview of the ongoing climate modeling activities in Belgium. 5. Provide coherent climate information for Belgium targeted to end-users, backed by: (i) a unified framework for the H-Res climate runs and (ii) uncertainty estimations on the climate change signal; 6. Provide and present a climate-impact report for stakeholders and the general public that highlight the most important results of the project.BRAIN-beBRAIN-be - Belgian Research Action through Interdisciplinary Network