Biogeochemical and mineralogical effects of Fe-P-S dynamics in sediments of continental shelf sea: Impact of salinity, oxygen conditions, and catchment area characteristics

Although continental shelf seas make up a relatively small fraction ( ca 7%) of the world ocean's surface, they are thought to contribute significantly (20–50% of the total) to the open-ocean carbon dioxide storage through processes collectively known as the shelf sea pump. The global significance of these processes is determined by the vertical mixing, which drives the net CO 2 drawdown (which can occur only in stratified water). In this paper, we focus on identifying the processes that are responsible for mixing across the thermocline in seasonally stratified shelf seas. We present evidence that shear instability and internal wave breaking are largely responsible for thermocline mixing, a clear development from the first-order paradigm for the water column structure in continental shelf seas. The levels of dissipation observed are quantitatively consistent with the observed dissipation rates of the internal tide and near-inertial oscillations. It is perhaps because these processes make such a small contribution to the total energy dissipated in shelf seas that they are not well represented in current state-of-the-art numerical models of continental shelf seas. The results thus present a clear challenge to oceanographic models.

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Reconstructing a 180 yr record of natural and anthropogenic induced low-oxygen conditions from Louisiana continental shelf sediments

Geology ◽

10.1130/g21341.1 ◽

2005 ◽

Vol 33 (4) ◽

pp. 329 ◽

Cited By ~ 44

Author(s):

Lisa E. Osterman ◽

Richard Z. Poore ◽

Peter W. Swarzenski ◽

R. Eugene Turner

Keyword(s):

Continental Shelf ◽

Low Oxygen ◽

Oxygen Conditions ◽

Shelf Sediments ◽

Louisiana Continental Shelf

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Occurrence and distribution of antibiotic resistance genes in sediments in a semi-enclosed continental shelf sea

The Science of The Total Environment ◽

10.1016/j.scitotenv.2020.137712 ◽

2020 ◽

Vol 720 ◽

pp. 137712

Author(s):

Yuxuan Zhang ◽

Jian Lu ◽

Jun Wu ◽

Jianhua Wang ◽

Yichen Lin

Keyword(s):

Antibiotic Resistance ◽

Continental Shelf ◽

Resistance Genes ◽

Antibiotic Resistance Genes ◽

Shelf Sea

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Global multi-scale segmentation of continental and coastal waters from the watersheds to the continental margins

Hydrology and Earth System Sciences ◽

10.5194/hess-17-2029-2013 ◽

2013 ◽

Vol 17 (5) ◽

pp. 2029-2051 ◽

Cited By ~ 89

Author(s):

G. G. Laruelle ◽

H. H. Dürr ◽

R. Lauerwald ◽

J. Hartmann ◽

C. P. Slomp ◽

...

Keyword(s):

Continental Shelf ◽

Co2 Flux ◽

Global Scale ◽

Continental Margins ◽

Emission Rates ◽

Large Marine Ecosystems ◽

Multi Scale ◽

Air Water Interface ◽

Shelf Seas ◽

Shelf Sea

Abstract. Past characterizations of the land–ocean continuum were constructed either from a continental perspective through an analysis of watershed river basin properties (COSCATs: COastal Segmentation and related CATchments) or from an oceanic perspective, through a regionalization of the proximal and distal continental margins (LMEs: large marine ecosystems). Here, we present a global-scale coastal segmentation, composed of three consistent levels, that includes the whole aquatic continuum with its riverine, estuarine and shelf sea components. Our work delineates comprehensive ensembles by harmonizing previous segmentations and typologies in order to retain the most important physical characteristics of both the land and shelf areas. The proposed multi-scale segmentation results in a distribution of global exorheic watersheds, estuaries and continental shelf seas among 45 major zones (MARCATS: MARgins and CATchments Segmentation) and 149 sub-units (COSCATs). Geographic and hydrologic parameters such as the surface area, volume and freshwater residence time are calculated for each coastal unit as well as different hypsometric profiles. Our analysis provides detailed insights into the distributions of coastal and continental shelf areas and how they connect with incoming riverine fluxes. The segmentation is also used to re-evaluate the global estuarine CO2 flux at the air–water interface combining global and regional average emission rates derived from local studies.

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Storm surges on a continental shelf

Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences ◽

10.1098/rsta.1965.0009 ◽

1965 ◽

Vol 257 (1082) ◽

pp. 351-383 ◽

Cited By ~ 39

Keyword(s):

Theoretical Analysis ◽

Continental Shelf ◽

Coriolis Force ◽

West Coast ◽

Deep Ocean ◽

Storm Surges ◽

Wind Fields ◽

The West ◽

Sea Bottom ◽

Shelf Sea

This paper gives a theoretical analysis of storm surges generated on a continental shelf by moving wind fields; surges generated in the ocean and propagated on to the shelf are also investigated. A continental shelf of uniform depth and width, bounded by a long straight coast and connected with an infinitely deep ocean, is considered. In studying the motion of the shelf sea, bottom friction and Coriolis force are taken into account, and it is supposed that conditions are the same in all vertical sections normal to the coast. The theory is applied to the problem of storm surges on the west coast of the British Isles. It is shown that these surges are generated by wind fields, associated with moving depressions, acting over the sea of the continental shelf to the south of Ireland. In two cases the observed surge at Milford Haven has been reproduced satisfactorily by the theory.

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