transparent gif


Ej inloggad.

Göteborgs universitets publikationer

Ventilation of the Baltic Sea deep water: A brief review of present knowledge from observations and models

Författare och institution:
H. E. M. Meier (-); R. Feistel (-); J. Piechura (-); Lars Arneborg (Institutionen för geovetenskaper); H. Burchard (-); V. Fiekas (-); N. Golenko (-); N. Kuzmina (-); V. Mohrholz (-); Christian Nohr (Institutionen för geovetenskaper, oceanografi); V. T. Paka (-); J. Sellschopp (-); A. Stips (-); V. Zhurbas (-)
Publicerad i:
Oceanologia, 48 s. 133-164
Artikel, refereegranskad vetenskaplig
Sammanfattning (abstract):
The ventilation of the Baltic Sea deep water is driven by either gale-forced barotropic or baroclinic salt water inflows. During the past two decades, the frequency of large barotropic inflows (mainly in winter) has decreased and the frequency of medium-intensity baroclinic inflows (observed in summer) has increased. As a result of entrainment of ambient oxygen-rich water, summer inflows are also important for the deep water ventilation. Recent process studies of salt water plumes suggest that the entrainment rates are generally smaller than those predicted by earlier entrainment models. In addition to the entrance area, the Slupsk Sill and the Slupsk Furrow are important locations for the transformation of water masses. Passing the Slupsk Furrow, both gravity-driven dense bottom flows and sub-surface cyclonic eddies, which are eroded laterally by thermohaline intrusions, ventilate the deep water of the eastern Gotland Basin. A recent study of the energy transfer from barotropic to baroclinic wave motion using a two-dimensional shallow water model suggests that about 30% of the energy needed below the halocline for deep water mixing is explained by the breaking of internal waves. In the deep water decade-long stagnation periods with decreasing oxygen and increasing hydrogen sulphide concentrations might be caused by anomalously large freshwater inflows and anomalously high mean zonal wind speeds. In different studies the typical response time scale of average salinity was estimated to be between approximately 20 and 30 years. The review summarizes recent research results and ends with a list of open questions and recommendations.
Ämne (baseras på Högskoleverkets indelning av forskningsämnen):
Geovetenskap och miljövetenskap
baltic sea, salt water inflows, deep water ventilation, entrainment, turbulent mixing, eastern gotland basin, scale atmospheric circulation, north-sea, thermohaline variability, numerical experiments, vertical circulation, salinity variations, cyclonic eddies, climate-change, ocean climate
Postens nummer:
Posten skapad:
2007-10-16 12:55
Posten ändrad:
2009-12-08 10:14

Visa i Endnote-format

Göteborgs universitet • Tel. 031-786 0000
© Göteborgs universitet 2007