Work package 1

Work package 2

Work package 3

Work package 4

Participants

Contact us

ProClim publications

Fieldwork and Instrumentation

NOClim main page


Integration and synthesis

Work package 4

Key personnel and responsibilities:
Helge Drange (NERSC):
Principal investigator, MICOM and Bergen Climate Model.

Post Doc (NERSC): Model and data integration on large scale.
W. Paul Budgell (IMR): ROMS, high resolution coupled atmosphere-ice-ocean model.
Harald Loeng (IMR): Observational data base, linkages and interpretation.
Randi Ingvaldsen Post Doc (IMR): Model and data integration on regional scale.

Activities
The IMR Post Doc and NERSC Post Doc and personnel from the other work packages will synthesize and quantify the observed and modelled interannual variability of dense water production modes in the entire region of interest, using the model formulations arrived at from achieved process understanding.
Results of these activities will be fed into the NOClim project office which will take special responsibility to ensure that consistent synthesis reports for the public are produced. This applies in particular for connections to studies of the meridional overturning in the North Atlantic - Nordic Seas.


Discussion, description and motivation:
It is an open question if and on which time scales formation of intermediate to deep waters at high latitudes is one of the controlling mechanisms for the large-scale ocean circulation, and then in particular for the Atlantic Thermohaline Circulation.

In this work package, a synthesis will be made to qualitatively and quantitatively construct time series of the volume flux and thermodynamic properties associated with formation of intermediate to deep water masses in the open Greenland Sea, along the Polar-Atlantic fronts in the northern Norwegian Sea, and on the Barents Sea shelves. The synthesis will cover the period of instrumental data, starting with the pioneering work of Helland-Hansen and Nansen in the beginning of the 20th century. All of the available observations will be used, including a unique data set of 130.000 hydrographic stations from Russia that is not included in the World Ocean Database (the data set is available at NERSC through collaboration with the Arctic and Antarctic Research Institute in St. Petersburg, Russia).

Furthermore, analyses of the available observations will be bridged by basin scale numerical ocean modelling. Three model tools will be used: A global version of the isopycnic coordinate ocean model MICOM with fully dynamic-thermodynamic sea ice. This model will be set up with a stretched horizontal grid with a typical resolution of about 20-by-20 km in the Nordic Seas. The model will be forced with daily re-analyses fields for the period 1948 to present. Existing simulations indicate that the model is able to describe the gross features of the ocean climate variability in the region. Secondly, a regional, high-resolution (few km) version of the ocean model ROMS will be applied to simulate the open ocean mixing and the shelf processes in the region. The global MICOM model will provide temporally and spatially consistent lateral boundary conditions for the regional ROMS model. Finally, a 500 years control integration and a 250 years scenario integration with the Bergen Climate Model will be analysed to assess the natural variability modes, possible changes in the characteristics of the modes as the human-induced greenhouse warming continues, and the role that formation of intermediate to deep waters in the Nordic Seas have on the Atlantic Thermohaline Circulation.


Til toppen av siden