Physical and biogeochemical processes in ice-covered lakes

Ice-covered lakes are facing pervasive changes in their ice-cover periods. Global observations reveal the decline in annual ice-on duration while forecasts of numerical models preclude massive changes of these systems in the next decades as a result of global warming. Understanding the links between the under-ice physics and biogeochemical processes is critical for anticipating the evolution and fate of ice-covered lakes and their ecosystems.

The goal of this interdisciplinary research study is to:

characterise radiatively-driven convection and mixing in ice-covered waters
test high-resolution vertical in-situ observations and new autonomous under water vehicles
determine the horizontal structure of convective cells
investigate the effect of convective mixing on phytoplankton
investigate the accumulation and release of greenhouse gases
develop mechanical energy and heat balances of under-ice waters
investigate the role lateral flows in the thermal evolution of ice-covered waters

 

Ulloa, H. N.,  Winters, K. B.,  Wüest, A., &  Bouffard, D.  (2019),  Differential heating drives downslope flows that accelerate mixed‐layer warming in ice‐covered waters. Geophysical Research Letters,  46, 13872– 13882. https://doi.org/10.1029/2019GL085258

Bouffard, D. G. Zdorovennova, S. Bogdanov, T. Efremova, S. Lavanchy, N. Palshin, A. Terzhevik, L. Råman Vinnå, S. Volkov, A. Wüest, R. Zdorovennov, H. N. Ulloa. Under-ice convection dynamics in a boreal lake. Inland Waters 9(2).  https://doi.org/10.1080/20442041.2018.1533356

Winters, K.B., H.N. Ulloa, A. Wüest, and D. Bouffard (2019). Energetics of radiatively-heated ice-covered lakes. Geophysical Research Letters. https://doi.org/10.1029/2019GL084182.

Ulloa, H.N., A. Wüest, and D. Bouffard (2018). Mechanical energy budget and mixing efficiency for a radiatively heated ice-covered waterbody. Journal of Fluid Mechanics 852: R1. doi:10.1017/jfm.2018.587.

Bouffard, D. and A. Wüest (2019). Convection in lakes. Annu. Rev. Fluid Mech. 51: 189 – 215. Doi: 10.1146/annurev-fluid-010518-040506.

Bouffard D., R.E. Zdorovennov, G.E. Zdorovennova, N. Pasche, A. Wüest and A.Y. Terzhevik (2016). Ice-covered Lake Onega: effects of radiation on convection and internal waves. EUROPEAN LARGE LAKES IV, Hydrobiologia 780: 21–36, doi: 10.1007/s10750-016-2915-3.

Natacha Pasche, Hilmar Hofmann, Damien Bouffard, Carsten J. Schubert, Petr A. Lozovik & Sebastian Sobek (2019): Implications of river intrusion and convective mixing on the spatial and temporal variability of under-ice CO2 , Inland Waters 9(2).  DOI: 10.1080/20442041.2019.1568073.