My focus will include conservative tracers, such as the stable isotope composition of natural waters, as well as particle-reactive materials carried in sea ice and within Arctic waters, such as natural and anthropogenic radionuclides. I will also use the St. Lawrence Island polynya region in the Bering Sea as an example of how biogeochemical process measurements can be integrated with biological oceanography to achieve a better understanding of ecosystem function. These experiments were designed to test the hypothesis that iron, an element that is highly insoluble in seawater, controls phytoplankton productivity in the Southern Ocean. Results will be presented from both meso-scale experiments, with particular reference to key processes in iron biogeochemistry that influence phytoplankton productivity and community structure. Stability of ice ridge shape and self-induced oscillations of sea ice cover.
Ice ridges are typical features of sea ice cover.
They are formed from ice blocks under the compression and shear of ice cover along cracklike faults or along contact lines of floes. Near coastline ridges influence on the distribution of ice stresses in the vicinity of shelf constructions and stipulate stability of fast ice location. Dynamic model of single ice ridge of arbitrary shape is constructed. Single ridge is considered as discontinuity line in continuous ice cover. Analysis of the laws of mass, impulse and energy conservation over the discontinuity line gives possibility to find the stresses between ridged and level ice and the equations describing variations of ridge shape during buildup process.