High latitude climate and climate variability
Associate Professor in the Department of Atmospheric and Oceanic Sciences
Office: Burnside Hall 823
Tel.: (514) 398-4369
Fax.: (514) 398-6115
bruno [dot] tremblay [at] mcgill [dot] ca (E-mail)
The presence of sea ice (and snow) at high latitudes plays an important role in the state and variability of the high latitude and global climate through various processes and feedback mechanisms. These include the ice-albedo feedback, the ventilation of the relatively warm ocean in leads in winter, the fluxes of salt and fresh water implied when ocean water freezes in one location while the ice melts in some other location, and the insulation effect sea ice which reduces the heat flux and momentum transfer between the atmosphere and the ocean.
I am interested in the high latitudes and their effect on global climate, and climate change. The idea of a summer ice-free Arctic (the Antarctic-analogue) is discussed more and more in the community. Important changes in the high latitude have already been observed. These include the melting of the permafrost, the warming of the eastern Arctic atmosphere, the reduction in ice extent and thinning of sea ice cover, the positive trend in Eurasian river runoff, etc. How will these changes impact the heat and fresh water budget of the Arctic? and the fresh water exchange between the Arctic and the northern North Atlantic where deep convection is present? Are these changes forced by local ocean-atmosphere interactions? or are they forced remotely (e.g. by the warming of the tropical Indian and western Pacific Oceans) through tele-connection patterns? How will negative feedbacks associated (for instance) with the potential increase in summer cloud cover and fresh water flux to the northern North Atlantic affect the response of the high latitude to this warming? In a globally warmed world, we expect an increased hydrological cycle. Can we see trends in high latitude precipitation in the instrumental record? Is this trend coherent with the trend in river runoff? etc. These are some of the questions that I am interested in tackling in the near future in my research.
- The study of the fresh water and heat budget of the Arctic Ocean (including both sea ice and the surface ocean waters) and its effect on the density driven ocean circulation. This work is done in collaborations with Lawrence Mysak and Alexandra Jahn from our department, and Peter Schlosser and Robert Newton from the Lamont Doherty Earth Observatory (LDEO) of Columbia University (CU).
- The transport of ice rafted debris in the Southern Ocean (as reconstructed from ocean cores) by iceberg and its relation with present day and past climate. This work is done in collaboration with Maria Abrahamovicz (from our department), Trevor Williams and Tina Van der Flierdt (LDEO), and Martin Roy (Université du Québec à Montréal).
- The study of sea ice deformation, and motion (rheology), and the energetics of sea ice. This work is done in collaboration with Jean-Francois Lemieux (from our department).
- The future of the perennial sea ice cover in the Arctic Ocean - and the relative importance of sea ice export, ocean-ice and air-ice heat fluxes in potentially creating a summer ice-free Arctic. This work is done in collaboration with Richard Cullather (LDEO).
- The effects of tides on air-sea interactions in ice-covered seas. This work is done in collaboration with Robin Robertson from the University of New South Whales.
- The effects of blowing snow (e.g. snow redistribution by wind, snow transport into leads, blowing snow sublimation) in sea ice environments and over ice sheets. This work is done in collaboration with Stephen Dery (University of Northern British Columbia - UNBC), Robin Bell, Michael Studinger, Katie Leonard (from LDEO), and Doug MacAyeal (University of Chicago).
- Transport of pollutant, sediment and nutrients by Arctic sea ice. This work is done in collaboration with Stephanie Pfirman (Barnard College), Robert Newton (LDEO), Kirk Cochran (University of Stony Brook), and Boswell Wing (from the Department of Earth and Planetary Sciences at McGill).
- Reconstruction of high latitude solid precipitation from observed snow depth records using an inverse modeling approach and a land surface model. This work is done with Jessie Cherry (University of Alaska), Stephen Dery (UNBC), Marc Stieglitz (Georgia Tech) and Gavin Gong (CU).
- The study of the relative effects of clouds and sea-ice concentration on the top of the atmosphere albedo. This work is done in collaboration with Irina Gorodetskaia, Beate Liepert and Marc Cane (LDEO).
Some recent publications
I. Gorodetskaia, M. Cane, B. Tremblay, A. Kaplan, "The effects of sea-ice and land-snow concentrations on planetary albedo from the Earth Radiation Budget Experiment", Atmos -Ocean, 44, 2006.
R. Newton, B. Tremblay, M. Cane, P. Schlosser, "A simple model of the Arctic Ocean response to annular atmospheric modes", J. Geophys. Res., in press, 2006.
I. V. Gorodetskaia, M. Cane, L.-B. Tremblay, A. Kaplan: ``The effects of sea ice and land snow concentrations on planetary albedo from the Earth Radiation Budget Experiment'', Atmos-Ocean, 44(2), 2006.
L.-B. Tremblay and M. Hakakian, ``Estimating the sea-ice compressive strength from satellite- derived sea-ice drift and NCEP reanalysis data'', in press, J. Phys. Oceanography, 2006.
J.E. Cherry, B. Tremblay, S. Dery and M. Stieglitz, "Reconstructing solid precipitation from snow depth measurements and a land surface model", Water Resource Research, 41, 2005.
H. Huwald, L.-B. Tremblay, H. Blatter: ``A multi-layer sigma-coordinate snow-ice thermodynamic: validation against SHEBA/SIMIP data'', J. Geophys. Res., 110, doi: 10.1029/2003\-JC002328, 2005.
H. Huwald, L.-B. Tremblay, H. Blatter: ``Reconciling different datasets from the Surface HEat Budget of the Arctic Ocean (SHEBA)'', J. Geophys. Res., 110, doi: 10.1029/2003\-JC002221, 2005.
L.Grieco, L.-B. Tremblay, E. Zambianchi, ``Transport Processes in the Gulf of Naples and Their Effects on Phytoplankton and Zooplankton Populations with a Prey-Predator Relationship'', Continental Shelf Research, 25, 711-728, 2005.
S. Dery and L.-B. Tremblay, ``Modelling the effects of wind redistribution on the snow mass budget of polar sea ice'', J. Phys. Oceanography, 34, 258--271, 2004.
G. Schmidt, C. Bitz, U. Mikolajewicz and L.-B.Tremblay. ``Ice ocean boundary conditions for coupled models'', Ocean Modelling, 7, 59--74, 2004.
K. Leonard, R. E. Bell, M. Studinger, B. Tremblay, ``Anomalous accumulation rates in the Vostok ice-core resulting from ice flow over Lake Vostok'', Geophys. Res. Letters, 31, L24401, doi:10.1029/2004GL021102, 2004.
Gorodetskaya, I. V., L.-B. Tremblay, M. Cane, B. Liepert, "The cloud phase and surface albedo effects on the shortwave radiation budget of the Arctic Ocean in coupled models and observations", J. Climate, under review.
Cherry, J. E., B. Tremblay, M. Stieglitz, S. Dery, "New estimates of Arctic solid precipitation 1940-1999", J. Hydrometeorology, under review.
L.-B. Tremblay and S. Dery, "Quantifying the effects of snow redistribution by wind on the Arctic Ocean snow mass budget", J. Climate, under review.