IMIS | Lifewatch regional portal

You are here


[ report an error in this record ]basket (0): add | show Print this page

Diapycnal mixing across the photic zone of the NE Atlantic
van Haren, H.; Brussaard, C.P.D.; Gerringa, L.J.A.; van Manen, M.H.; Middag, R.; Groenewegen, R. (2021). Diapycnal mixing across the photic zone of the NE Atlantic. Ocean Sci. 17: 301-318.

Additional data:
In: Ocean Science. Copernicus: Göttingen. ISSN 1812-0784; e-ISSN 1812-0792, more
Peer reviewed article  

Available in  Authors 

Authors  Top 
  • van Haren, H., more
  • Brussaard, C.P.D., more
  • Gerringa, L.J.A., more
  • van Manen, M.H., more
  • Middag, R., more
  • Groenewegen, R., more


    Variable physical conditions such as vertical turbulent exchange, internal wave, and mesoscale eddy action affect the availability of light and nutrients for phytoplankton (unicellular algae) growth. It is hypothesized that changes in ocean temperature may affect ocean vertical density stratification, which may hamper vertical exchange. In order to quantify variations in physical conditions in the northeast Atlantic Ocean, wesampled a latitudinal transect along 17 ± 5 W between 30 and 63  N in summer. A shipborne conductivity–temperature–depth (CTD) instrumented package was used with a custom-made modification of the pump inlet to minimize detrimental effects of ship motions on its data. Thorpe-scale analysis was used to establish turbulence values for the upper 500 m from three to six profiles obtained in a short CTD yo-yo, 3 to 5 h after local sunrise. From south to north, average temperature decreased together with stratification while turbulence values weakly increased or remained constant. Vertical turbulent nutrient fluxes did not vary significantly with stratification and latitude. This apparent lack of correspondence between turbulent mixing and temperature is likely due to internal waves breaking (increased stratification can support more internal waves), acting as a potential feedback mechanism. As this feedback mechanism mediates potential physical environment changes in temperature, global surface ocean warming may not affect the vertical nutrient fluxes to a large degree. We urge modellers to test this deduction as it could imply that the future summer phytoplankton productivity in stratified oligotrophic waters would experience little alterations in nutrient input from deeper waters.

All data in the Integrated Marine Information System (IMIS) is subject to the VLIZ privacy policy Top | Authors