Interaction of rising frazil with suspended particles: tank experiments with applications to nature

Enrichment of nutrients, exopolymeric substances and microorganisms in newly formed sea ice on the Mackenzie shelf

“…1, open circles), despite these stations having the highest concentrations of inorganic sediments in the sea ice and average bacterial concentrations (average of 4 stations: 0.8 × 10 9 cells l -1 ) in the surface water (Table 1). This suggests that inorganic sediments, efficiently scavenged by frazil in the Arctic (Reimnitz et al 1993), are not a major pathway by which bacteria entered the sea ice. In our samples, bacteria were not observed to be attached to inorganic sediments, although this attachment may have been disturbed during sample preparation.…”

“…This same process leads to the accumulation of microorganisms in newly formed sea ice (Garrison et al 1983, Reimnitz et al 1993. Suspension freezing occurs under cold, turbulent conditions, which can lead to a supercooled water column.…”

Key role of organic complexation of iron in sustaining phytoplankton blooms in the Pine Island and Amundsen Polynyas (Southern Ocean)

“…The presence of unsaturated organic ligands may promote the stabilization of this regenerated Fe by keeping it in solution and preventing aggregation and sinking. The regenerated Fe can be immediately utilized by plankton or become trapped along with organic matter when sea-ice forms later in the season (Kepkay, 1994;Thomas et al, 2001;Lannuzel et al, 2007Lannuzel et al, ,2008Ackermann et al, 1994;Reimnitz et al, 1993;Sherwood, 2000;Smedsrud, 1998). This material, together with organic matter produced by the microbial community living within the sea-ice, are released the following season when the sea-ice melts (Lannuzel et al, 2010) and act as a source of dissolved ligands (Aguilar-Islas et al, 2008;Calace et al, 2001;Nichols et al, 2005;Pankowski and McMinn, 2008).…”

Numerical model of frazil ice and suspended sediment concentrations and formation of sediment laden ice in the Kara Sea

“…Disks that are initially small and tend not to stick to sediment particles during collisions evolve into large complex aggregates that are capable of sweeping up sediment particles along their rising path [Reimnitz et al, 1993a;Kempema et al, 1993]. Treatment of changes in particle populations and characteristics is clearly required to model correctly the ice-ice, sedimentsediment, and ice-sediment interactions, and progress toward this capability has been made for sediment [e.g., Hill and Nowell, 1995] and for ice [Svensson and Omstedt, 1994;1998;Hammar and Shen, 1995].…”