Data/hora: 08/06/2024 13:52:45

Provedor de dados: | 5
País: | France
Título: | Small-scale melt processes governing the flushing of nutrients from a first-year sea-ice, Hudson-Bay, canada
Autores: | Hudier, E; Ingram, G.
Data: | 1994
Ano: | 1994
Resumo: | This work formed part of a multi disciplinary research programme conducted 25 km offshore of Kuujjuarapik in southeastern Hudson Bay (Canadian Arctic). Large differences in salinity and nutrient concentration between brine, ice and under-ice surface water were used to study the different phases observed during the period of melt initiation. We present a discussion of processes governing the flushing of brine and the development of a melt layer below first-year sea ice. Phosphate, nitrate + nitrite and silicic acid distributions within the first 30 cm below the ice are described. Three distinct steps were observed during the melt initiation: a phase of brine rejection; a phase of flushing associated with the development of a buoyant melt layer rich in nutrients; and a phase of melt of the ice-water interface characterized by the development of a melt layer poor in nutrients. The flux of brine during the four days of brine flushing was estimated at 0,009 m(3)/day/m(2) (i.e. equivalent to a melt rate of 9 mm/day). Our findings confirm that exchanges between the water column and the sea-ice sheet are dominated by tidal current fluctuations. The increase of current velocities provoked the pumping of a fraction of the bottom-ice brine content and a dissipation of vertical structures. Low tidal velocity periods created conditions suitable for the development of a melt layer.
Tipo: | Text
Idioma: | Inglês
Identificador: | http://archimer.ifremer.fr/doc/00098/20900/18513.pdf
Editor: | Gauthier-Villars
Relação: | http://archimer.ifremer.fr/doc/00098/20900/
Formato: | application/pdf
Fonte: | Oceanologica Acta (0399-1784) (Gauthier-Villars), 1994 , Vol. 17 , N. 4 , P. 397-403