Defend Hudson Bay !

A fun part of being a grad student, is making bonds beyond the regular "have-to-share-the-same-open-area-office" friendship. The challenges to overcome are so tough, the emotions shared are so strong than you can never break those bonds. So last week was emotional for me, as I assisted to the Ph.D. thesis defence of my last two buddies from my grad school modeling lab.

Both worked on the Hudson Bay system, a very exciting environment to work on. It's the southernmost Arctic sea, a transition zone between the Arctic Ocean and the Atlantic Ocean at the forefront of the impacts of the current global warming.

Pierre St-Laurent defended brilliantly the 17th of May his thesis entitled "Variabilité saisonnière et interannuelle des eaux douces dans les mers Arctiques : Le cas de la baie d'Hudson".

Pierre showed the audience how the fresh-water budget is regulated in the Hudson Bay. He tackled both liquid and solid (seasonal sea-ice) aspects of it. As an example of how great a tool is modeling in a well formed scientific mind, he first studied this issue with a realistic high resolution sea-ice / ocean 3-D circulation model of the Hudson Bay, developed in the numerical modeling lab of ISMER in Rimouski.

He then constructed an idealized system to sort out the relative importance of the various hydrological, atmospheric and oceanic forcing.

This allowed him to demonstrate for the first time the role of changing wind regimes in the periodic retention/expulsion of fresh water from the Hudson Bay towards the North-West Atlantic.

Pierre will soon lend his brain as a post-doc to the Old Dominion University in Norfolk, VA

(He's too modest to agree for me to tell you that there is a tenure track position attached at the end of his 3 years as post-doc).

Virginie Sibert defended not less brilliantly the 20th of May her thesis entitled "Modélisation de la variabilité saisonnière et de la sensibilité au climat des productions glacielle et pélagique de la baie d'Hudson".

Virginie managed to build a model of primary and secondary production within the sea-ice in Hudson Bay.

She coupled this to the ice compartment of the same high-resolution 3-D circulation model than Pierre. After characterizing the spatio-temporal patterns of this system, she coupled it further with an NPZD pelagic production model to have a complete picture of the primary production in the system.

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After a rigorous validation process which guaranteed a good confidence in the model results, she finally tested one of the IPCC scenario of climate change (A2) for the Hudson Bay system.

A nice outcome of her work is that the Hudson Bay system would not, for its most part, pass a tipping point yet. Primary production of both ice algea and phytoplankton would increase, even if their respective blooms would occur sooner in the season.

Virginie has already brought her talent and charm as a post-doc in the IFREMER lab of Brest, France.