Overview of the 2005 Montreal Urban Snow Experiment (MUSE-2005) Mario Benjamin Bruno Harvey Frédéric Chagnon Gilles Morneau Jocelyn Mailhot Stéphane Bélair Aude Lemonsu CRTI Urban Canyon Project (0093RD) Annual Meeting – Dorval – August Meteorological Service of Canada

Objectives Document the evolution of surface characteristics and energy budgets in a dense urban area during the winter-spring transition –Evolution of snow cover from ~100% to 0% in an urban environment –Impact of snow on the surface energy and water budgets –Quantify anthropogenic fluxes in late winter and spring conditions Evaluate TEB in reproducing the surface characteristics and budgets in these conditions Gain expertise in urban measurements Prepare for a wider effort to be submitted to CFCAS

Acknowledgements Prof Sue Grimmond, Indiana University Prof Tim R. Oke, University of British Columbia Prof James A. Voogt, University of Western Ontario Sarah M. Roberts This project was funded by CBRN Research and Technology Initiative as project # RD

Selection of the site Selection of Montreal –Large city with significant accumulation of snow (2.14 m/year) –Representative of Eastern Canada winter climate –Availability of technical staff –Meso-scale surface meteorological network –Wind profiler, RASS, McGill weather radar Residential location seeked –Horizontal homogeneity, two and three-storey attached buildings –Away from tall buildings and trees, rivers, mountains, parks Easy and safe access to the site

N 1 km Selection of the site

Incoming and outgoing radiation CNR1 radiometer Kipp & Zonen Radiative surface temperatures IR camera in heated case Turbulent fluxes by eddy covariance 10Hz 3D sonic anemometer CSAT3 H 2 O/CO 2 analyzer Li-Cor 7500 Fine wire thermocouple ASPTC Air temperature and humidity in canyons Radiative temperature of walls Continuous measurements 17 March to 14 April m tower

Intensive observation periods Clear skies and southwest winds Four 26-hour IOPs (March 17-18, 22-23, 30-31, April 5-6) Measurements: –Hourly radiative surface temperatures using IR thermometer –Albedo (5 daytime measurements) –Snow depth and density (5 daytime measurements) –Pictures to document snow cover, snow melt, wet fraction

Radiative temperatures and roof snow fraction from IR camera 18 March March 2005 Sidewalk Street Roof

Infrared temperatures

Frozen portion of the roof pixels used by images

17 March 22 March 30 March 5 April Alley Street Evolution of snow cover

Evolution of snow depth

Evolution of snow density

Radiation measurements

Turbulent fluxes

Next steps Complete the quality control and post-processing of the data Format the data into an easy-to-use database Estimate anthropogenic heat using energy consumption data Evaluation of TEB Preparation of the second phase –Rural, suburban and urban sites

The MUSE-2005 team Project management: Michel Jean Jocelyn Mailhot Mario Benjamin Station installation Bruno Harvey Frédéric chagnon IOP manual measurements Stavros Antonopoulos Najat Benbouta Mario Benjamin Frédéric Chagnon Olivier Gagnon Bruno Harvey Aude Lemonsu Gilles Morneau Radenko Pavlovic Weather briefings Jean Morissette Robert Michaud Evaluation of TEB Stéphane Bélair Aude Lemonsu Claude Pelletier