Lake Baikal

Lake Baikal (Siberia) is a unique system. It is the largest surface freshwater reservoir in the world, it harbours an incredible amount of endemic species at all trophic levels, and its sediments are a climate archive of exceptional quality. More information on Lake Baikal is available the Lake Baikal Homepage.

In collaboration with the Limnological Institute of the Siberian Branch of the Russian Academy of Science, the Department of Applied Physics at the Irkutsk State University, and several other partners, we investigate the mixing processes and the cycling of nutrients and methane within the lake.

Mixing processes

Despite its enormous depth of more than 1600 m, the lake is oxygenated down to the deepest reaches. This is due to on the one hand a very efficient turbulent transport within the extremely weakly stratified water body, and the other hand regularly occurring intrusions of water masses plunging from the surface to the bottom of the lake. We are studying the mechanisms that lead to both the turbulent and the advective deep-water renewal, using moored thermistors and current meters, vertical profiles of temperature and conductivity, and temperature microstructure profiles.

Cycling of nutrients and methane

Based on our knowledge about the mixing processes in the lake, combined with data from sediment traps and sediment cores, we estimated the internal fluxes of nutrients within the lake [...]

Lake Baikal is also the only lake containing significant amounts of methane hydrates. Previous estimates indicated that it could be a significant source of methane to the atmosphere. Based on numerous measurements of methane concentrations in the water (performed by Pacific Oceanological Insitute in Vladivostok) and the near-surface air (Institute of Atmospheric Optics, Tomsk), we estimated the large-scale methane fluxes within the lake and between the lake and the atmosphere.

Publications

• Schmid M., Budnev N.M., Granin N.G., Sturm M., Schurter M., Wüest A. (2008) Lake Baikal deepwater renewal mystery solved. Geophysical Research letters, Vol. 35, L09605, doi:10.1029/2008GL033223 [pdf, 882KB]
• Schmid M., De Batist M., Granin N.G., Kapitanov V.A., McGinnis D.F., Mizandrontsev I.B., Obzhirov A.I., Wüest A. (2007) Sources and sinks of methane in Lake Baikal: A synthesis of measurements and modeling. Limnol. Oceanogr., 52(5), 1824–1837 [pdf, 2.57MB]
  
• Müller B., Maerki M., Schmid M., Vologina E.G., Wehrli B., Wüest A., Sturm M. (2005) Internal carbon and nutrient cycling in Lake Baikal: sedimentation, upwelling, and early diagenesis. Global and Planetary Change 46 (1-4), 101-124, doi:10.1016/j.gloplacha.2004.11.008 [pdf, 700KB]
  
• Wüest A., Ravens T.M., Granin N.G., Kocsis O., Schurter M., Sturm M. (2005) Cold intrusions in Lake Baikal: direct observational evidence for deep-water renewal. Limnology and Oceanography 50 (1), 184-196. [pdf, 598KB]
  
• Ravens, T.M., O. Kocsis, A. Wüest and N. Granin (2000) Small-scale turbulence and vertical mixing in Lake Baikal, Limnol. Oceanogr. 45 : 159-173. [pdf, 293KB]