Search

This study investigated the temporal variability and changes in snow cover duration and the average snow depth from December to April in the Pyrenees at 1,500 and 2,100 m a.s.l. for the period 1958–2017. This is the first such analysis for the entire mountain range using SAFRAN‐Crocus simulations run for this specific purpose. The SAFRAN‐Crocus simulations were evaluated for the period 1980–2016 using 28 in situ snow depth data time series, and for the period 2000–2017 using MODIS observations of the snow cover duration. Following confirmation that the simulated snow series satisfactorily reproduced the observed evolution of the snowpack, the Mann–Kendall test showed that snow cover duration and average depth decreased during the full study period, but this was only statistically significant at 2,100 m a.s.l. The temporal evolution in the snow series indicated marked differences among massifs, elevations, and snow variables. In general, the most western massifs of the French Pyrenees underwent a greater decrease in the snowpack, while in some eastern massifs the snowpack did not decrease, and in some cases increased at 1,500 m a.s.l. The results suggest that the trends were consistent over time, as they were little affected by the start and end year of the study period, except if trends are computed only starting after 1980, when no significant trends were apparent. Most of the observed negative trends were not correlated with changes in the atmospheric circulation patterns during the snow season. This suggests that the continuous warming in the Pyrenees since the beginning of the industrial period, and particularly the sharp increase since 1955, is a major driver explaining the snow cover decline in the Pyrenees. [ABSTRACT FROM AUTHOR]

The article presents an atmospheric reanalysis over France performed with the Safran-gauge-based analysis system for the period 1958-2008. It states that long-term mean values, inter-annual and seasonal variability of the Safran 50-year analysis were presented for all computed variables including rainfall, snowfall, and mean air temperature. It notes that researchers assess the reanalysis through various validation experiments with both dependent and independent data.

Ski tourism plays a major role in European mountain areas such as the Alps, Pyrenees, Scandinavia, Turkey, Eastern European Mountains etc. Meteorological conditions govern the operating conditions of ski resorts, due to their reliance on natural snow fall and favorable conditions for snowmaking. However, there is currently a major lack of assessment of past and future operating conditions of ski resorts at the pan-European scale in the context of climate change. The presented work aims at filling this gap, as part of the ongoing development of "European Tourism" Sectoral Information System (SIS) of the Copernicus Climate Change Services (C3S). C3S is run by the European Center for Medium-range Weather Forecast (ECMWF) on behalf of the European Commission. The Mountain Tourism Meteorological and Snow Indi-cators (MTMSI) are derived using statistical adjustment of EURO-CORDEX climate projections (multiple GCM/RCM pairs for several RCP) using the UERRA 5.5 km resolution surface reanalysis as a reference, followed by snowpack models runs using the Crocus multi-layer model, with and without snow manage-ment options (grooming, snowmaking). Results are generated by 100 m elevation bands for NUTS-3 geographical areas spanning all mountainous areas in Europe. The resulting data can be aggregated in time and space in various ways, depending on the use case. The presentation quickly introduces the un-derpinning elements for the generation of this product, and illustrates results at the pan-European scale as well as for smaller scale case studies, for past and future climate conditions. The data will be made available freely through the Copernicus Data Store starting in 2019. It is expected that the data and the tools developed within this project will not only make it possible to analyze the climate sensitivity of ski tourism in Europe as a topical yet academic research question, but would also help third-parties in devel-oping climate services specifically targeting the ski tourism industry in Europe. [ABSTRACT FROM AUTHOR]

The SIM hydro-meteorological model is used in operation at Météo-France since 2003 for real time hydro-meteorological monitoring. It is also part of a real-time ensemble mid term prediction system and allows climate change impact studies as well as seasonnal forecast experiments. An hydro-meteorological system based on SIM, called SIM-PS, was first developped for demonstration in the frame of the European FP7 EUPORIAS project. It was then improved to provide real time seasonnal prediction over France each month. The Météo-France-system6 meteorological forecasts presently drive SIM model. A quantile-quantile correction of temperature and precipitation forecasts is previously applied. SIM predicts streamflows and soil moisture fields among other variables. A quantile-quantile adaptation of streamflow is also applied. Finally, SIM-PS forecasts are made available on a french website dedicated to seasonnal forecasts. An evaluation of those forecasts using a 24-year hindcast will be presented. The forecasted streamflows will be compared to the SIM reanalysis through statistical scores. A focus will be made on the low flows forecasts. SIM-PS is also used to produce so-called « climatological seasonnal forecasts ». The hydrological SIM simulation starts from the current initial soil moisture state and is driven by meteorological forcings from the past climatology. This kind of approach provides end-users with scenarii that happened previously but taking the current soil moisture situation into account. This system allows to assess the impact of the initial hydrological state (soil moisture, snow cover) on the hydrological forecasts. This is of high interest in some cases, such as a particularly dry period like the 2017 summer and autumn over France. The performances of both systems, Météo-France-system6 based seasonnal forecasts and climatological seasonnal forecasts, will be compared, particularly for low flow forecasts. Moreover, in the frame-work of the french AQUI-FR project, a new hydro-geological modelisation plateform is being developped. This platform aims at performing detailed hydro-geological analysis and forecasts over France. It gathers existing groundwater modeling tools, developped by the partners of the project. Within the next few months, the AQUI-FR platform is expected to replace the hydro-geological model MODCOU in the SIM system. In this context, the AQUI-FR platform was run to produce seasonnal hydro-geological forecasts, using the water fluxes derivated from SIM-PS. The streamflow forecasts performed with AQUI-FR for a 24-year hindcast will be compared to the one performed with the MODCOU model within SIM-PS. A focus will be made on the forecasts issued on the 1st of May for low flow prediction. [ABSTRACT FROM AUTHOR]