دورية أكاديمية

Meridional Overturning and Heat Transport From Argo Floats Displacements and the Planetary Geostrophic Method (PGM): Application to the subpolar North Atlantic.

التفاصيل البيبلوغرافية
العنوان: Meridional Overturning and Heat Transport From Argo Floats Displacements and the Planetary Geostrophic Method (PGM): Application to the subpolar North Atlantic.
المؤلفون: Colin de Verdière, Alain, Meunier, Thomas, Ollitrault, Michel
المصدر: Journal of Geophysical Research. Oceans; Aug2019, Vol. 124 Issue 8, p6270-6285, 16p
مصطلحات موضوعية: MERIDIONAL overturning circulation, HEAT transfer, HYDROSTATICS, BAROTROPIC equation
مصطلحات جغرافية: NORTH Atlantic Region
مستخلص: A direct method is presented to obtain the meridional overturning and heat transport in oceanic basins from observations under the sole assumptions of geostrophy and hydrostatics. The method is made possible because of the rising Argo float displacements database that can provide a reference level at 1000 dbar for the time mean circulation at 1° × 1° resolution. To achieve the overturning and heat transport objectives, the absolute geostrophic time mean circulation must have nondivergent barotropic transports and this requires the solutions of two Poisson equations with suitable boundary conditions, one for the geopotential at 1000 dbar and one for the barotropic stream function. Applied to the subpolar Atlantic for the period 2000–2009, an overturning of 16–18 Sv is found around 40–50°N, and a meridional heat transport of 0.59 petawatt (PW, 1 PW = 1015 W) is found at 40°N (0.23 PW at 60°N) so that on average ~50 W/m2 is exported from ocean to atmosphere to feed the atmospheric storm track. The zonally averaged flow (the overturning) falls short of explaining the observed heat transport, and the barotropic component of the circulation accounts for up to 50% of the heat transport poleward of 55°N. With the rising Argo float database, the method offers high potential to reconstruct the World Ocean time mean circulation and its heat transport away from the equator at higher resolution. The drawback is that it requires in some critical places additional current observations on the shallow shelves that are not sampled by the Argo floats. Key Points: A new direct method to estimate absolute circulation from Argo float displacements and temperature‐salinity from World Ocean AtlasThe method also allows to estimate overturning stream function and meridional heat transport; it is applied in the subpolar North Atlantic [ABSTRACT FROM AUTHOR]
Copyright of Journal of Geophysical Research. Oceans is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
قاعدة البيانات: Complementary Index
الوصف
تدمد:21699275
DOI:10.1029/2018JC014565