Future climate of Brussels and Paris for the 2050s under the A1B scenario

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Reinitialised versus continuous regional climate simulations using ALARO-0 coupled to the land surface model SURFEXv5

Dynamical downscaling in a continuous approach using initial and boundary conditions from a reanalysis or a global climate model is a common method for simulating the regional climate. The simulation potential can be improved by applying an alternative approach of reinitialising the atmosphere, combined with either a daily reinitialised or a continuous land surface. We evaluated the dependence of the simulation potential on the running mode of the regional climate model ALARO coupled to the land surface model Meteo-France SURFace EXternalisee (SUR-FEX), and driven by the ERA-Interim reanalysis. Three types of downscaling simulations were carried out for a 10-year period from 1991 to 2000, over a western European domain at 20 km horizontal resolution: (1) a continuous simulation of both the atmosphere and the land surface, (2) a simulation with daily reinitialisations for both the atmosphere and the land surface and (3) a simulation with daily reinitialisations of the atmosphere while the land surface is kept continuous. The results showed that the daily reinitialisation of the atmosphere improved the simulation of the 2m temperature for all seasons. It revealed a neutral impact on the daily precipitation totals during winter, but the results were improved for the summer when the land surface was kept continuous. The behaviour of the three model configurations varied among different climatic regimes. Their seasonal cycle for the 2m temperature and daily precipitation totals was very similar for a Mediterranean climate, but more variable for temperate and continental climate regimes. Commonly, the summer climate is characterised by strong interactions between the atmosphere and the land surface. The results for summer demonstrated that the use of a daily reinitialised atmosphere improved the representation of the partitioning of the surface energy fluxes. Therefore, we recommend using the alternative approach of the daily reinitialisation of the atmosphere for the simulation of the regional climate

Local impact analysis of climate change on precipitation extremes : are high-resolution climate models needed for realistic simulations?

This study explores whether climate models with higher spatial resolutions provide higher accuracy for precipitation simulations and/or different climate change signals. The outputs from two convection-permitting climate models (ALARO and CCLM) with a spatial resolution of 3-4 km are compared with those from the coarse-scale driving models or reanalysis data for simulating/projecting daily and sub-daily precipitation quantiles. Validation of historical design precipitation statistics derived from intensityduration-frequency (IDF) curves shows a better match of the convection-permitting model results with the observations-based IDF statistics compared to the driving GCMs and reanalysis data. This is the case for simulation of local subdaily precipitation extremes during the summer season, while the convection-permitting models do not appear to bring added value to simulation of daily precipitation extremes. Results moreover indicate that one has to be careful in assuming spatial-scale independency of climate change signals for the delta change downscaling method, as high-resolution models may show larger changes in extreme precipitation. These larger changes appear to be dependent on the timescale, since such intensification is not observed for daily timescales for both the ALARO and CCLM models

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

Evaluation of a commercial IgG monotest assay: a new automated chemiluminescent immunoassay for the serodiagnosis of cystic echinococcosis

Background: Cystic echinococcosis (CE) is a zoonotic disease caused by the tapeworm Echinococcus granulosus complex. The geographical distribution is worldwide with variable incidences. In Belgium, only few imported cases are reported each year. Serodiagnosis of CE is performed by using a combination of immunoassays which are mainly based on crude hydatid antigens. The Belgian National Reference Laboratory, has evaluated the CE-IVD Hydatidosis VirClia® IgG chemiluminescent immunoassay and compared it with two other immunoassays. Methods: A total of 79 sera were retrospectively included from 15 patients with CE, 29 with alveolar echinococcosis, 16 with toxocariasis and 19 negative controls. Three immunoassays were compared: the Hydatidosis VirClia® IgG monotest assay which was run on the Virclia® Lotus (Vircell, Spain); the Ridascreen® Echinococcus IgG assay (R-Biopharm, Germany) and the Bordier® Echinococcus granulosus IgG ELISA (Bordier, Switzerland), which were tested on the ETI-Max 3000 immunoassay analyzer (DiaSorin, Italy). The McNemar test is used for statistical analysis. Results: All three methods showed 100% sensitivity. Regarding specificity, the Ridascreen® (78.1%) and VirClia® (76.6%) assays showed comparable performance (p-value: 1), while the Bordier® assay had poor results (54,7%) (p-value: 0,0007). The Bordier® assay showed 76% cross-reactions with E. multilocularis (22/29) and 31% with Toxocara sp. (5/16), while the VirClia® assay showed 51,7% (15/29) and no cross-reaction with Toxocara antigens. For Ridascreen® assay, 34% and 19% cross-reactions were observed for E. multilocularis (10/29) and Toxocara sp. (3/16), respectively. Non-specific reactions in negative controls were only observed with the Ridascreen® (1/19) and Bordier® assays (2/19). The shortest turnaround time was observed with Virclia® Lotus: 1 hour versus 3 hours for two other assays. Conclusions: All assays showed very high sensitivity. However, regarding specificity, the VirClia® performs better than the Bordier® and similarly to the Ridascreen® assay. Besides, the ready-to-use monotest format offers many advantages such as a quicker methodology and a reduced workflow. Therefore, the VirClia® assay is an efficient screening method for the detection of CE but should always be combined with an immunoblot assay to assess the specificity

Genetic diversity of Echinococcus multilocularis specimens isolated from Belgian patients with alveolar echinococcosis using EmsB microsatellites analysis.

The genetic diversity of Echinococcus multilocularis (E. multilocularis) specimens isolated from patients with alveolar echinococcosis (AE), is a major field of investigation to correlate with sources of infection, clinical manifestations and prognosis of the disease. Molecular markers able to distinguish samples are commonly used worldwide, including the EmsB microsatellite. Here, we report the use of the EmsB microsatellite polymorphism data mining for the retrospective typing of Belgian specimens of E. multilocularis infecting humans. A total of 18 samples from 16 AE patients treated between 2006 and 2021 were analyzed through the EmsB polymorphism. Classification of specimens was performed through a dendrogram construction in order to compare the similarity among Belgian samples, some human referenced specimens on the EWET database (EmsB Website for the Echinococcus Typing) and previously published EmsB profiles from red foxes circulating in/near Belgium. According to a comparison with human European specimens previously genotyped in profiles, the 18 Belgian ones were classified into three EmsB profiles. Four specimens could not be assigned to an already known profile but some are near to EWET referenced samples. This study also highlights that some specimens share the same EmsB profile with profiles characterized in red foxes from north Belgium, the Netherlands, Luxembourg and French department near to the Belgian border. Furthermore, Belgian specimens present a genetic diversity and include one profile that don't share similarities with the ones referenced in the EWET database. However, at this geographical scale, there is no clear correlation between EmsB profiles and geographical location. Further studies including additional clinical samples and isolates from foxes and rodents of south Belgium are necessary to better understand the spatial and temporal circumstances of human infections but also a potential correlation between EmsB profiles and parasite virulence

Molecular typing of Belgian Echinococcus multilocularis specimens from alveolar echinococcosis human lesions using EmsB microsatellites analysis

peer reviewedBackground. The genetic diversity of Echinococcus multilocularis (Em) is a major field of investigations to correlate with sources of infection or variable clinical manifestations of the alveolar echinococcosis (AE). Molecular markers able to distinguish strains are already used such as EmsB microsatellites. This marker is present in about 40 copies in the Em genome. Here, we report the use of EmsB microsatellite polymorphism for the typing of Belgian specimens isolated from patients with AE between 2019 and 2020. Material and methods. Total genomic DNA was isolated from liver, pleural fluid and bile samples using a DNA extraction kit for tissue (Qiagen). The PCR was performed according to Knapp et al, 2020. The EmsB A primer was 5’-labeled with FAM-fluorochrome. Fragment size analysis was performed on an ABI3500 automatic sequencer (ThermoFisher). The fluorescence signal was detected by colorimetric reading. Correspondences were established to assess the size of the amplified fragments using Gene mapper (ThermoFisher). “R studio” was used to generate a distance matrix, calculate the Euclidian distance and obtain a UPGMA method dendrogram in order to assess the similarity among samples. The profiles obtained were compared with those included in the EWET data collection. Results Seven specimens have been successfully analyzed. According to a comparison with European samples previously characterized (Knapp et al., 2020), 3 Belgian specimens shared the same P5 genomic profile while one strain had a P8 profile. These P5 and P8 strains were included into European profiles with strains from France, Switzerland and Germany. The three other isolates could not be classified into existing profiles but were placed between P6 and P7 profiles. Five strains originated from patients living in Wallonia, the Southern part of Belgium (Namur, Hainaut and Luxembourg) while the two others originated from neighboring provinces (Walloon Brabant and Bruxelles). Conclusions The EmsB microsatellites analysis allowed to genotypically characterize Em clinical specimens isolated in Belgium for the first time. This study highlights that some samples share the same genotypic profile but that heterogenetic diversity exist in Belgium. Some profiles are unique and differ from other European profiles. Further studies including more clinical samples are ongoing