Ecohydrology Seminar Series: Dr. Marek Stastna

Tuesday, December 8, 2015 2:00 pm - 2:00 pm EST (GMT -05:00)

High-order simulations in environmental fluid dynamics: from boundary layer turbulence to basin scale motions

Presented by Dr. Marek Stastna

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Associate Dean, Computing, Faculty of Mathematics 

Director, Mathematics Faculty Computing Facility

Professor, Department of Applied Math, University of Waterloo

​Abstract

The motion of naturally occurring fluids spans a range of scales from the size of the basin (10s of kilometers for our lakes like Lake Ontario) down to dissipation occurring on sub-millimeter length scales.  In this talk I will review two complementary numerical modeling approaches.  The first concerns the interaction of waves in the interior of the coastal ocean (so-called internal waves) with the ocean bottom.  In extreme cases, this interaction can lead to the resuspension of sediment from the ocean bottom.  I will argue that a much more robust result is that internal waves increase the rate of exchange of material across the bottom boundary layer, with possible implications for biogeochemical exchange.  The second approach I will discuss concerns basin scale motions in lakes with complex shape, such as those found on the Canadian Shield.  After reviewing the form large scale motions in lakes take, I will give examples of how commonly used numerical models go wrong. I will discuss a technique developed in our group that  has the potential to greatly improve the realism of lake scale simulations in complex basins.  I will end the talk with some speculation on future directions.

​Coffee provided. Bring your mug.