data analysis; vertical motion; quasi-geostrophic motion, synopticity; relocation; sampling strategy
Abstract :
[en] The quantification of vertical motion and vertical fluxes is essential in our ability to predict and tolerate climate change. However, diagnostic estimations might be affected by the errors arising from the necessary compromise between spatio-temporal resolution and cost of hydrographic surveys. Observations of a numerical ocean model have been made in order to test the accuracy of different sampling strategies and their possible a-posteriori corrections. A simple first-order correction method, computing a pseudo-synoptic data set from a non-synoptic data set and involving a geostrophic relocation of the stations is shown to correct significantly the synopticity error in hydrographic data, derived QG vertical motion and vertical temperature fluxes. Sensitivity analyses also show that the lack of synopticity is more critical than other factors, including the sampling resolution, the level of no-motion and the analysis. (C) 2001 Elsevier Science Ltd. All rights reserved.
Research center :
Centre Interfacultaire de Recherches en Océanologie - MARE - GHER
Disciplines :
Earth sciences & physical geography
Author, co-author :
Rixen, Michel
Beckers, Jean-Marie ; Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > Océanographie physique
Allen, J. T.
Language :
English
Title :
Diagnosis of vertical velocities with the QG Omega equation: a relocation method to obtain pseudo-synoptic data sets
Publication date :
2001
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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