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Montréal, Canada

Xu Z.,Maurice Lamontagne Institute | Savard J.-P.,Ouranos Consortium | Lefaivre D.,Maurice Lamontagne Institute
Atmosphere - Ocean | Year: 2015

This study demonstrates that long-term climate model solutions can be efficiently converted to storm surge time series at points of interest (POIs) for the future. The all-source Green's function (ASGF) regression model is used for this conversion. In addition to being data assimilative, the ASGF regression model can also simulate storm surges at a POI faster than the traditional modelling approach by orders of magnitude. This is demonstrated using the tidal gauge at Sept-Îles (Quebec, Canada) in the Gulf of St. Lawrence as the POI. First the ASGF regression model is used to assimilate 32 years of tidal gauge data, producing a continuous hindcast of storm surges and a set of best-estimate regression parameters. Second, the ASGF regression model with the best-estimate parameters is used to convert a Canadian Regional Climate Model solution (CRCM/AHJ) to an hourly time series of storm surges from 1961 to 2100. Gumbel's extreme value analysis (EVA) is then applied to the time series as a whole and also to tri-decadal segments. The tri-decadal approach is used to investigate whether there is any progressive shortening or lengthening of storm surge return periods as a result of future climate change. A method for correcting for bias due to the forcing field at the EVA level is also demonstrated. © 2015 © 2015 Taylor & Francis.

Rapaic M.,Service Meteorologique du Canada | Brown R.,Environment Canada | Markovic M.,Canadian Center for Meteorological and Environmental Prediction | Chaumont D.,Ouranos Consortium
Atmosphere - Ocean | Year: 2015

The spatial and temporal consistency of seasonal air temperature and precipitation in eight widely used gridded observation-based climate datasets (CANGRD, CRU-TS3.1, CRUTEM4.1, GISTEMP, GPCC, GPCP, HadCRUT3, and UDEL) and eight reanalyses (20CR, CFSR, ERA-40, ERA-Interim, JRA25, MERRA, NARR, and NCEP2) was evaluated over the Canadian Arctic for the 1950-2010 period. The evaluation used the CANGRD dataset, which is based on homogenized temperature and adjusted precipitation from climate stations, as a reference. Dataset agreement and bias were observed to exhibit important spatial, seasonal, and temporal variability over the Canadian Arctic with the largest spread occurring between datasets over mountain and coastal regions and over the Canadian Arctic Archipelago. Reanalysis datasets were typically warmer and wetter than surface observation-based datasets, with CFSR and 20CR exhibiting biases in total annual precipitation on the order of 300 mm. Warm bias in 20CR exceeded 12°C in winter over the western Arctic. Analysis of the temporal consistency of datasets over the 1950-2010 period showed evidence of discontinuities in several datasets as well as a noticeable increase in dataset spread in the period after approximately 2000. Declining station networks, increased automation, and the inclusion of new satellite data streams in reanalyses are potential contributing factors to this phenomenon. Evaluation of trends over the 1950-2010 period showed a relatively consistent picture of warming and increased precipitation over the Canadian Arctic from all datasets, with CANGRD giving moistening trends two times larger than the multi-dataset average related to the adjustment of the station precipitation data. The study results indicate that considerable care is needed when using gridded climate datasets in local or regional scale applications in the Canadian Arctic. © 2015 Taylor & Francis.

Roy-Dufresne E.,McGill University | Logan T.,Ouranos Consortium | Simon J.A.,McGill University | Chmura G.L.,McGill University | Millien V.,McGill University
PLoS ONE | Year: 2013

The white-footed mouse (Peromyscus leucopus) is an important reservoir host for Borrelia burgdorferi, the pathogen responsible for Lyme disease, and its distribution is expanding northward. We used an Ecological Niche Factor Analysis to identify the climatic factors associated with the distribution shift of the white-footed mouse over the last 30 years at the northern edge of its range, and modeled its current and potential future (2050) distributions using the platform BIOMOD. A mild and shorter winter is favouring the northern expansion of the white-footed mouse in Québec. With more favorable winter conditions projected by 2050, the distribution range of the white-footed mouse is expected to expand further northward by 3° latitude. We also show that today in southern Québec, the occurrence of B. burgdorferi is associated with high probability of presence of the white-footed mouse. Changes in the distribution of the white-footed mouse will likely alter the geographical range of B. burgdorferi and impact the public health in northern regions that have yet to be exposed to Lyme disease. © 2013 Roy-Dufresne et al.

Smargiassi A.,University of Montreal | Smargiassi A.,Institute National Of Sante Publique Du Quebec | Goldberg M.S.,McGill University | Wheeler A.J.,Health Canada | And 8 more authors.
Environmental Research | Year: 2014

Objective: The acute cardiorespiratory effects of air quality among children living in areas with considerable heavy industry have not been well investigated. We conducted a panel study of children with asthma living in proximity to an industrial complex housing two refineries in Montreal, Quebec, in order to assess associations between their personal daily exposure to air pollutants and changes in pulmonary function and selected indicators of cardiovascular health. Methods: Seventy-two children with asthma age 7-12 years in 2009-2010 participated in this panel study for a period of 10 consecutive days. They carried a small backpack for personal monitoring of sulphur dioxide (SO2), benzene, fine particles (PM2.5), nitrogen dioxide (NO2) and polycyclic aromatic hydrocarbons (PAHs) and underwent daily spirometry and cardiovascular testing (blood pressure, pulse rate and oxygen saturation). To estimate these associations, we used mixed regression models, adjusting for within-subject serial correlation, and for the effects of a number of personal and environmental variables (e.g., medication use, ethnicity, temperature). Results: Children with asthma involved in the study had relatively good pulmonary function test results (mean FEV1 compared to standard values: 89.8%, mean FVC: 97.6%, mean FEF25-75: 76.3%). Median diastolic, systolic blood pressures and oxygen saturation were 60/94mmHg and 99%, respectively. Median personal concentrations of pollutants were NO2, 5.5ppb; benzene, 2.1μg/m3; PM2.5, 5.7μg/m3; and total PAH, 130μg/m3. Most personal concentrations of SO2 were below the level of detection. No consistent associations were observed between cardio-pulmonary indices and personal exposure to PM2.5, NO2 and benzene, although there was a suggestion for a small decrease in respiratory function with total concentrations of PAHs (e.g., adjusted association with FVC: -9.9ml per interquartile range 95%CI: -23.4, 3.7). Conclusions: This study suggests that at low daily average levels of exposure to industrial emissions, effects on pulmonary and cardiovascular functions in children with asthma may be difficult to detect over 10 consecutive days. © 2014 Published by Elsevier Inc.

Guay C.,Hydro - Quebec | Minville M.,Hydro - Quebec | Braun M.,Ouranos Consortium
Canadian Water Resources Journal | Year: 2015

This paper presents the methodology and results of a vast study on climate change impacts on hydrology for the province of Québec for the 2050 horizon. A climate ensemble was first built with simulations from the World Climate Research Programme (WCRP)'s Coupled Model Intercomparison Project phase 3 (CMIP3) multi-model dataset, the North American Regional Climate Change Assessment Program (NARCCAP) and the Canadian Regional Climate Model (CRCM) operational runs. Direct outputs and post-processed data from the climate simulations were used as input to the calibrated HSAMI hydrological model in order to produce a large ensemble of hydrological projections for 305 Québec watersheds. Simulations results indicate that increases in mean annual streamflow are projected for the whole province, with greater changes (up to 14%) in the north. The intra-annual distribution of streamflow also changes, with higher winter flows and lower summer flows as well as apparently earlier spring floods. The maximum height of the snow cover and the number of days with snow on the ground are likely to diminish for the 2050 horizon for the southern half of the province, while the northern half will see more snow, but a shorter snow season as well. © 2015 Canadian Water Resources Association.

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