The 1998 Ice Storm

The 1998 Ice Storm was one of the most devastating meteorological event in Canadian history. Freezing precipitation fell between January 4th and January 10th 1998. The Ice Storm seriously affected the electricity supply to 3.5 million people, shut down transportation, restricted emergency services, damaged farms and trees, and damaged personal property. The longest residential blackouts lasted 33 days and 4 in 5 trees on Montreal’s Mount Royal were damaged. The mobilization of the Canadian Armed Forces for relief effort was the largest humanitarian assistance mobilisation in history. There were an estimated 28 deaths in Canada and 19 in the United States and $4 billion of damage caused by the Ice Storm in Canada and the United States with $1 billion of damage in New York and Maine. We are carrying out studies of the internal structure of this storm with a focus on its kinematic, thermodynamic and microphysical properties. We use a variety of datasets to assist us including Doppler radar, satellites, operational model products and surface observations.

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Winter Precipitation

Winter precipitation can be in the form of snow, rain, freezing rain, ice pellets or wet snow. The conditions leading to one or another of these can be very similar but the impacts can vary enormously. Despite the obvious importance of this issue, relatively little research has been conducted on the physical mechanisms producing such precipitation. In addition, the phase changes associated with the production of the various types of winter precipitation lead to the heating and/or cooling of the atmosphere as well as to its moistening and/or drying. Such changes alter the thermodynamic, moisture and dynamic environment within which subsequent precipitation is formed. To address this overall issue we carry out detailed observations of winter precipitation and its associated environment and we also simulate the formation of the precipitation in detailed process models.

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ArcticNet

ArcticNet is a huge research activity addressing climate change and adaptation to it in the Arctic. The area which we are focusing on is atmospheric-related hazards. This includes an examination of hazards such as strong winds, heavy precipitation, blizzards, freezing precipitation, and wind chill. We aim to better understand how such conditions occur and to use such information to assess how they may change in the future. We work with local communities in the Arctic in a two-way manner to learn from them what are hazardous conditions and to share our progress with them so that they can better adapt.

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Storm Studies in the Arctic (STAR)

The focus of STAR is on extreme weather affecting Baffin Island and Iqaluit. Pilot projects are being undertaken to begin to understand the storms afecting this region and an intensive field experiment is planned for 2007. This field experiment will involve Doppler radar, a surface mesonet, research aircraft with dropsondes, remote sensing of moisture as well as detailed precipitation observations. Our main focal points are the structure and evolution of the storms, their detailed nature in the vicinity of Iqaluit, and cloud and precipitation fields associated with the storms. A team of university and government scientist is being brought together to examine these storms. STAR is also contributing to ArcticNet activities, in particular the component concerned with meteorological hazards.

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Drought Research Initiative (DRI)

The focus of DRI is on the recent devastating drought that occurred over the Canadian Prairies form 1999-2004. It has been suggested that this was Canada's worst natural disaster. A team of university and government scientists from across the country is being pulled together to better understand and better predict such droughts. The main focus of our research is better understanding the role of major storms on the structure and evolution of the drought. Several major storms occurred around the edges of the drought region over this 5 year drought period and major storms brought the drought to an end. To achieve our goals, we will be analyzing operational Doppler radar information that covers this region, satellite information, surface data, as well as operational and research model results.

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CloudSat

CloudSat is a multi-satellite, multi-sensor experiment designed to measure those properties of clouds that are critical for understanding their effects on both weather and climate. These properties of clouds are not obtainable from current satellite measurement systems. The mission's primary science goal is to furnish data needed to evaluate and improve the way clouds are parameterized in global models, thereby contributing to better predictions of clouds and thus to the poorly understood cloud-climate feedback problem.

The key observations are the vertical profiles of cloud liquid water and ice water contents and related cloud physical and radiative properties. The spacecraft payload consists of a millimeter-wave radar. CloudSat flies in tight formation with the CALIPSO satellite carrying a backscattering lidar, and these two satellites will follow behind the Aqua satellite in a somewhat looser formation. The combination of data from the CloudSat radar with coincident measurements from CALIPSO and Aqua provides a source of information that can be used to assess the role of clouds in both weather and climate. CloudSat along with the CALIPSO satellite was launched in April 2006.

We are using CloudSat information and associated A-Train data to examine several issues. These include the occurrence of precipitation type transition regions over Canada and globally as well as the distribution of cloud and precipitation over the Canadian Archipelago, the Canadian Prairies, and the West Coast Mountains. To address such issues, initial studies will be concerned with validation. These will have two components. First of all, we will contribute to validation studies over southern Ontario. Second, we will carry out validation within the 2007 STAR field experiment in the Canadian Arctic.

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Instruments and Data

Our group uses, or aims to use, a wide variety of instruments and data. One of the main sources of data is from the National Radar Project (NRP) set of radars which includes the McGill Radar at Ste Anne de Bellevue. For more information about the radar network click here, for the McGill radar click here. Our group owns and utilizes a weather station which is currently in operation in Nunavut. Check out our Extreme Photos pages for pictures. We are also in the process of assembling a Precipitation Occurrence Sensing System (POSS) unit so that we can use it during mixed phase precipitation events and try and examine the mesoscale structures of these events in conjunction with the NRP radars.

A POSS unit ontop of Burnside Hall at McGill University

We also use online data such as the Weather Recording and Analysis Package (WRAP).

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Journal Articles

Szeto, K.K., R.E. Stewart, M.K. Yau and J.R. Gyakum, 2006: Northern tales: a synthesis of MAGS atmospheric and hydrometeorological research. Bull. Amer. Meteor. Soc. (Submitted)

Szeto, K.K., H, Tran, M. MacKay, R. Crawford, and R.E. Stewart, 2006: MAGS Water and energy budget study. J. Hydrometeorol. (Submitted)

Nawri, N. and R.E. Stewart, 2006: Channelling of high-latitude boundary layer flow over complex terrain. Boundary Layer Meteorol. (Submitted)

Theriault, J. and R.E. Stewart, 2006: On the effect of vertical air motion on winter precipitation types. Natural Hazards and Earth System Sciences (Submitted)

Henson, W. and R.E. Stewart, 2006: Severity and return periods of icing events in the Montréal area. Atmos. Res. (Accepted)

Gibson, S. and R.E. Stewart, 2006: Observations of ice pellets in a winter storm. Atmos. Res. (Conditionally Accepted)

Henson, W.L., R.E. Stewart, B. Kochtubajda, 2006: On the precipitation and related features of the 1998 Ice Storm in the Montreal - Ottawa area. Atmos. Res. (Accepted)

Nawri, N. and R.E. Stewart, 2006: Climatological features of orographic low-level jets within Frobisher Bay. Atmos.-Ocean (Accepted)

Theriault, J.M., R.E. Stewart, M.K. Yau and J.A. Milbrandt, 2006: On the simulation of winter precipitation types. J. Geoph. Res. (Accepted)

Roberts, E., R.E. Stewart and C.A. Lin, 2006: A study of drought characteristics over the Canadian Prairies. Atmos.-Ocean (Accepted)

Kochtubajda, B., M.D. Flannigan, J.R. Gyakum, R.E. Stewart, K. Logan and T-V Nguyen, 2006: Lightning and forest fires in the Northwest Territories: current activity and responses to future climate change. Arctic, 59, 211-221

Ralph, M.F., R.M. Rauber, B.F. Jewett, D.E. Kingsmill, P. Pisano, P. Pugner, R.M. Rasmussen, D.W. Reynolds, T.W. Schlatter, R.E. Stewart, J.S. Waldstricher, 2005: Improving short term (0-48 hour) cool season quantitative precipitation forecasting: recommendations from a USWRP workshop. Bull. Amer. Meteor. Soc., 86, 1619-1632.

Inithar, M.R. and R.E. Stewart, 2005: Extratropical cyclones and precipitation within the Canadian Archipelago during the cold season. Arctic, 58, 162-174.

Stewart, R.E., J.E. Burford, D.R. Hudak, B. Currie, B. Kochtubajda, P. Rodriguez and J. Liu, 2004: Weather systems occurring over Fort Simpson, Northwest Territories, Canada during three seasons of 1998/99. Part 2: precipitation features. J. Geophys. Res., 109, D22109, doi: 10.1029/2004JD004929.

Hudak, D., B. Currie, R.E. Stewart, P. Rodriguez, J. Burford, N. Bussieres and B. Kochtubajda, 2004: Weather systems occurring over Fort Simpson, Northwest Territories, Canada during three seasons of 1998/99. Part 1: cloud features. J. Geophys. Res., 109, D22108, doi: 10.1029/2004JD004876.

Lawford, R.G., R.E Stewart, T. Yasunari, H. J. Isemer, M. Manton, J. Marengo, T. Koike, S. Benedict, P. Kabat, T. Lebel, J. Roads and P. Try, 2004: Advancing global and continental scale hydrometeorology: a summary of the contributions of the GEWEX Hydrometeorology Panel (GHP). Bull. Amer. Meteor. Soc., 85, 1917-1930.

Liu, J., R.E. Stewart and K.K. Szeto, 2004: Moisture transport and other hydrometeorological features associated with the severe 2000/01 drought over the Canadian Prairies. J. Climate, 17, 305-319.

Liu, J. and R.E. Stewart, 2003: Water vapour features over the Saskatchewan River basin. J. Hydrometeor., 4, 944-959.

Rouse, W.R., E.M. Blyth, R.W. Crawford, J.R. Gyakum, J.R. Janowicz, B. Kochtubajda, H.G. Leighton, P. Marsh, L. Martz, A. Pietroniro, H. Ritchie, W.M. Schertzer, E.D. Soulis, R.E. Stewart, G.S. Strong, and M.K. Woo, 2003: Energy and water cycles in a high latitude, north-flowing river system: summary of results from the Mackenzie GEWEX Study - Phase 1. Bull. Amer. Meteor. Soc., 84, 73-87.

Stewart, R.E. and J.E. Burford, 2002: On the features of clouds occurring over the Mackenzie River basin. J. Geoph. Res., AAC18, 1-13.

Roads, J., M. Kanamitsu and R.E. Stewart, 2002: Continental-scale experiment water and energy budgets in the NCEP-DOE reanalysis II. J. Hydrometeor., 3, 227-248.

Stewart, R.E. et al., 2002: Hydrometeorological features of the Mackenzie basin climate system during the 1994/1995 water year: a period of record low discharge. Atmos.-Ocean, 40, 257-278.

Stewart, R.E., 2002: Towards understanding water and energy processes of the Mackenzie River basin. Atmos.-Ocean, 40, 91-94.

Liu, J., H.-R. Cho and R.E. Stewart, 2002: Characteristics of water vapor transport over the Mackenzie River basin during the 1994-95 water year. Atmos.-Ocean, 40, 101-111.

Kochtubajda, B., R.E. Stewart, J.R. Gyakum, and M.D. Flannigan, 2002: Summer convection and lightning over the Mackenzie River basin and their impacts during 1994 and 1995. Atmos.-Ocean, 40, 199-220.

Cao, Z., M. Wang, B.P. Proctor, G.S. Strong, R.E. Stewart, H. Ritchie, and J.E. Burford, 2002: On the physical processes governing the water budget of and the discharge from the Mackenzie basin for the 1994/95 water year. Atmos.-Ocean, 40, 125-143.

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Conference Articles

Stewart, R.E. and J. Pomeroy, 2006: Drought Research Initiative: a study of the severe 1995-2005 drought over the Canadain Prairies. AGU, San Francisco.

Stewart, R.E., 2006: Drought, storms and water budgets. DRI Workshop, Saskatoon.

Nawri, N., R. Stewart and E. Roberts, 2006: Climatology and forcing of strong boundary-layer winds at coastal communities of Nunavut. Coastal Zone Canada Conf., Tuktoyaktuk.

Roberts, E., N. Nawri, S. Gibson and R.E. Stewart, 2006: The characteristics and evolution of storm systems over southern Baffin Island. CMOS Congress, Toronto.

Cox, J., R. Stewart and C. Lin, 2006: Snow water equivalent in Canada: climatology and forecasting. Northeast Storm Conf., Vermont.

Stewart, R.E., 2006: Extreme events impacts analysis project. Coordinated Enhanced Observing Period Workshop, UNESCO, Paris.

Stewart, R.E., 2006: A recent major drought over the Canadian Prairies. Coordinated Enhanced Observing Period Workshop, UNESCO, Paris.

Stewart, R.E., 2006: Drought: a case study over the Canadian Prairies. Workshop on International Global Water Cycle and its Observation, UNESCO, Paris.

Nawri, N., R.E. Stewart, E. Roberts, G.W.K. Moore and J. Hanesiak, 2006: Climatology and forcing of strong boundary-layer winds in mountainous regions of the eastern Canadian Arctic. Second Intl. Green Energy Conf., Oshawa, Ontario.

Cox, J., R. Stewart and C. Lin, 2006: Snow water equivalent in Canada: climatology and forecasting. CMOS Congress, Toronto.

Hanesiak, J., R. E. Stewart, K. Moore, P. Taylor, D. Barber, G. McBean, B. Kochtubajda and D. Hudak, 2006: Storm Studies in the Arctic (STAR) – A CFCAS Major Initiative. CMOS Congress, Toronto.

Roberts, E., N. Nawri, S. Gibson and R.E. Stewart, 2006: The characteristics and evolution of storm systems over southern Baffin Island. European Geoph. Union, Vienna.

Theriault, J. and R.E. Stewart, 2006: On the simulation of winter precipitation types. European Geoph. Union, Vienna.

Nawri, N., E. Roberts, S. Gibson and R.E. Stewart, 2005: Atmospheric hazards over the eastern Arctic. Second ArcticNet Workshop, Banff.

Nawri, N., E. Roberts, S. Gibson and R.E. Stewart, 2005: The structure and evolution of severe winter storms over Southern Baffin Island. Second ArcticNet Workshop, Banff.

Roberts, E. and R.E. Stewart, 2005: Freezing rain over the eastern Canadian Arctic. Second ArcticNet Workshop, Banff.

Nawri, N. and R.E. Stewart, 2005: The climatology and associated features of orographic low-level Jets within Frobisher Bay. Second ArcticNet Workshop, Banff.

Pomeroy, J. and R.E. Stewart, 2005: The Canada DRI, a new Drought Research Initiative for the Canadian Prairies. AGU Conference, San Francisco.

Stewart, R.E., W. Henson, J. Theriault and S. Gibson, 2005: Hazardous icing storms and their precipitation. IAMAS Conference, August 2-11, Beijing.

Cox, J., R.E. Stewart, C.A. Lin, V. Turcotte and B. Kochtubajda, 2005: Initial results on the forecasting of snowfall to snow water equivalent ratio by a new model. CMOS Congress, Vancouver.

Gibson, S. and R.E. Stewart, 2005: Characteristics of ice pellets during a winter storm. CMOS Congress, Vancouver.

Henson, W. and R.E. Stewart, 2005: The mesoscale structure of the 1998 Ice Storm and probability of occurrence of similar ice storms. Intl. Wkshp. on Atmos. Icing of Structures, Montreal.

Nawri, N. and R.E. Stewart, 2005: Orographic low-level jets: a climatology for Iqaluit, Nunavut. CMOS Congress, Vancouver.

Theriault, J. and R.E. Stewart , 2005: Numerical studies on winter precipitation type formation. CMOS Congress, Vancouver.

Theriault, J. and R.E. Stewart , 2005: Winter precipitation types and icing at the surface . Intl. Wkshp. on Atmos. Icing Structures, Montreal.

Stewart, R.E. and N. Nawri, 2004: Extreme weather events over the eastern Arctic. ArcticNet Workshop, Quebec City.

Stewart, R.E., 2004: Atmospheric moisture and circulation features occurring over the Canadian Prairies during 2000/01. Canadian Prairie Drought Workshop. Calgary.

Henson, W. and R.E. Stewart, 2004: The mesoscale structure and the probability of occurrence of the 1998 Ice Storm. 8th International Conf. Precipitation. Vancouver.

Kochtubajda, B., M.D. Flannigan, K.A. Logan and R.E. Stewart, 2004: Convection, lightning-initiated fires and climate change In the Northwest Territories of Canada. Symposium Climate Change in the Arctic, Reykjavik, Iceland.

Theriault, J., R.E. Stewart, J. Milbrant and M.K. Yau, 2004: On the production of winter precipitation types and associated visibility changes, CMOS Congress, Edmonton.

Roberts, E., R.E. Stewart and C.A. Lin, 2004: Small scale characteristics of Canadian Prairie drought, CMOS Congress, Edmonton.

Theriault, J., R.E. Stewart, J. Milbrant and M.K. Yau, 2004: Winter precipitation formation and its impact on visibility, AGU Spring Conf., Montreal.

Roberts, E., R.E. Stewart and C.A. Lin, 2004: The structure of severe drought over the Canadian Prairies, AGU Spring Conf., Montreal.

Stewart, R.E., 2004: Extremes during CEOP. AGU Spring Conf., Montreal.

Kochtubajda, B., M.D. Flannigan, J.R. Gyakum, R.E. Stewart and A.Way, 2003: Lightning behaviour in the Northwest Territories, Canada. AGU Fall Conf., San Francisco.

Stewart, R.E., 2003: Winter precipitation. Proc. Symposium on Extreme Weather. IUGG, Sapporo, Japan.

Stewart, R.E., 2003: GEWEX and the water cycle. Proc. CMOS Congress, Ottawa, 3.

Stewart, R.E., J. Liu and K.K. Szeto, 2003: A severe drought over the Canadian Prairies. Proc. Conf. European Geoph. Union, Nice, France.

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Theses Published

Gibson, S., 2005: Detailed observations of ice pellets and an analysis of their characteristics and formation mechanisms. M.Sc., McGill University.

Cox, J., 2005: Snow water equivalent and its prediction over Canada. M.Sc., McGill University.

Roberts, E., 2004: A Study of Drought Characteristics over the Canadian Prairies. M.Sc., McGill University.

Thériault, J., 2004: Numerical Studies on Winter Precipitation Type. M.Sc., McGill University.

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