Time filter

Source Type

Turcotte R.,Center dexpertise hydrique du Quebec | Filion T.-C.F.,Center dexpertise hydrique du Quebec | Lacombe P.,Center dexpertise hydrique du Quebec | Fortin V.,Center Meteorologique Canadien | And 2 more authors.
Hydrological Sciences Journal | Year: 2010

Operational hydrology has to provide a reliable forecast of the spring flood events over the territory of Quebec. Hydrological models using ground observed snow water equivalent (SWE) as an initial condition are applied for this purpose. However, these models face major difficulties when trying to simulate the final part of the spring flood. This paper presents an original approach for calibrating and feeding the hydrological models with vertical inflows from snowmelt and rain, corrected continuously using bi-monthly observed SWE. This method, tested on the River du Nord catchment, helps to improve the quality of the spring flood simulation. Significant errors remain, leading to the conclusion that, at least in part, the snow observation methods commonly used in Quebec may be the source of the problem. This paper also considers the idea that another part of the explanation might be in the - as yet difficult to prove - presence of a new snow monster. © 2010 Centre d'expertise hydrique du Québec.

Lespinas F.,CNRS Training and Research Center on Mediterranean Environments | Lespinas F.,Center Meteorologique Canadien | Ludwig W.,CNRS Training and Research Center on Mediterranean Environments | Heussner S.,CNRS Training and Research Center on Mediterranean Environments
Journal of Hydrology | Year: 2014

This paper investigates the uncertainties associated with using regional climate models and one hydrological model calibrated from non-stationary hydroclimatic time series to simulate future water resources of six Mediterranean French coastal river basins. First, a conceptual hydrological model (the GR2M model) was implemented in order to reproduce the observed river discharge regimes. Climatic scenarios were then constructed from a set of Regional Climate Models (RCMs) outputs and fed into the hydrological model in order to produce water discharge scenarios for the 2071-2100 period. At last, an assessment of uncertainties associated with the hydrological scenarios is given.With respect to the 1961-1990 period, RCMs project a mean annual temperature increase of 4.3-4.5. °C (3.1-3.2. °C) under the IPCC A2 (B2) scenario. Precipitation changes, although more variable, indicate a decrease between -10% and -15.6% for A2 and between -6.1% and -11.6% for B2. As a result, the GR2M model simulates a general water discharge decrease between -26% (-14%) and -54% (-41%) for the A2 (B2) scenario, depending on the basin of interest.Sensitivity tests on the hydrological modelling revealed that the hydrological scenarios are sensitive to the choice of the PE formulation, although this climatic input is negligible in the model calibration. Also, a slight but significant drift between the modelled and observed time series was detected for most basins, indicating that the hydrological model fails to adapt to non-stationary discharge conditions. A simple correction method based on a dynamical parametrization of one model parameter with temperature data considerably reduces the model drift in half of the investigated basins. When extrapolated this new parametrization to the future climate scenarios, decrease of water discharge is found to be twice as great as estimated from the standard parametrization. Our results suggest that the uncertainties stemming from hydrological models with fixed parametrizations should be further addressed in any climate change impact study. © 2014.

Lemieux J.-F.,Recherche en Prevision Numerique Environnementale | Beaudoin C.,Recherche en Prevision Numerique Environnementale | Dupont F.,Center Meteorologique Canadien | Roy F.,Recherche en Prevision Numerique Environnementale | And 12 more authors.
Quarterly Journal of the Royal Meteorological Society | Year: 2015

In recent years, the demand for improved environmental forecasts in the Arctic has intensified as maritime transport and offshore exploration increase. As a result, Canada has accepted responsibility for the preparation and issuing services for the new Arctic MET/NAV Areas XVII and XVIII. Environmental forecasts are being developed based on a new integrated Arctic marine prediction system. Here, we present the first phase of this initiative, a short-term pan-Arctic 1/12° resolution Regional Ice Prediction System (RIPS). RIPS is currently set to perform four 48 h forecasts per day. The RIPS forecast model (CICE 4.0) is forced by atmospheric forecasts from the Environment Canada regional deterministic prediction system. It is initialized with a 3D-Var analysis of sea ice concentration and the ice velocity field and thickness distribution from the previous forecast. The other forcing (surface current) and initialization fields (mixed-layer depth, sea surface temperature and salinity) come from the 1/4° resolution Global Ice Ocean Prediction System. Three verification methods for sea ice concentration are presented. Overall, verifications over a complete seasonal cycle (2011) against the Ice Mapping System ice extent product show that RIPS 48 h forecasts are better than persistence during the growth season while they have a lower skill than persistence during the melt period. A better representation of landfast ice, oceanic processes (wave-ice interactions, upwelling events, etc.) in the marginal ice zone and better initializing fields should lead to improved forecasts. © 2015 The Authors and Environment Canada.

Discover hidden collaborations