[en] Climatological analyses of a historical data base have been carried out with the aim of reconstructing the three-dimensional temperature and salinity fields in the Mediterranean Sea. Seasonal and monthly distributions of hydrographic properties have been computed by a variational inverse method as an alternate to the standard Gandin (1969; Objective analysis of meterological fields, Israeli Program for Scientific Translation, Jerusalem) procedure. The spline solutions of the minimization problem are demonstrated to be numerically and theoretically equivalent to field estimates obtained by conventional objective analysis. The application of a finite-element technique allows analysis to be performed in the model space rather than in the observational space, which substantially improves the numerical efficiency of the procedure. The parameters of the scheme are adjusted according to the statistics of the climatological data. The results,realized as gridded data sets (horizontal resolution of 0.25 degrees), show some trends in seasonal variability affecting the properties of water masses. As expected, the upper layer is subject to a well-defined seasonal signal affecting both the temperature and salinity fields. Error maps, reflecting the degree of uncertainty in the analyses, have been systematically produced. The present work is conceived as a basic support to more advanced studies such as diagnostic calculations, initialization of dynamical models, assimilation of hydrological data into primitive equation models, or planning of experimental surveys. New versions of the climatological fields will be released as data are added to the historical data base. Copyright (C) 1996 Elsevier Science Ltd.
Disciplines :
Earth sciences & physical geography
Author, co-author :
Brasseur, P.
Beckers, Jean-Marie ; Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > Océanographie physique
Brankart, J. M.
Schoenauen, R.
Language :
English
Title :
Seasonal temperature and salinity fields in the Mediterranean Sea: Climatological analyses of a historical data set
Publication date :
1996
Journal title :
Deep-Sea Research. Part I, Oceanographic Research Papers
ISSN :
0967-0637
eISSN :
1879-0119
Publisher :
Pergamon Press - An Imprint of Elsevier Science, Oxford, United Kingdom
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