Assimilation of Hydrographic Data from the Atlantic Inflow Experiment into Ocean Models
Abstract
Forecasts of oceanic circulation phenomena to be useful in naval operational systems require a hierarchy of numerical models that describe the permanent features and predict the variability of the ocean dynamics. The ability of understanding the structure and dynamics of the ocean will improve acoustic propagation prediction. Central to this effort is the development of techniques to integrate into numerical models various types of environmental measurements which are distributed randomly in time and space and have differing error characteristics. This report represents the link between the observational and numerical programs of the GIN Sea Project of SACLANTCEN. Hydrographic data are assimilated through a new procedure into 3D field distributions that can be used to initialise and update ocean circulation models. Most ocean circulation models start the computations by assuming the ocean to be at rest, requiring a large amount of computer time for the dynamics coming in to balance. One way to increase the computational efficiency is to supply an initial velocity field compatible with the model formulation and the data distributions. From the processed temperature and salinity distributions, initial velocities are computed using the inverse method developed at the Centre. Data from the GIN Sea '86 cruise of the Atlantic Inflow Experiment serve as prototype for the development of this technique. The resulting environmental conditions as derived for model initialization can be used directly for the analysis of the environmental conditions of the region. Comparison with the corresponding climatological distributions indicates the permanent features and the associated variability of the region of interest. Further work will be directed towards the integration of the procedure into3D time-dependent ocean dynamics models, and towards a similar analysis of other hydrographic data sets collected in the GIN Sea region.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 01, 1989
- Accession Number
- AD1114963
Entities
People
- G. Peggion
Organizations
- SACLANT ASW Research Centre