scholarly journals Steric sea level variations over 2004-2010 as a function of region and depth: Inference on the mass component variability in the North Atlantic Ocean

2011 ◽  
Vol 38 (15) ◽  
Author(s):  
W. Llovel ◽  
B. Meyssignac ◽  
A. Cazenave
Keyword(s):  
Atlantic Ocean ◽  
Sea Level ◽  
North Atlantic ◽  
North Atlantic Ocean ◽  
Steric Sea Level ◽  
The North ◽  
Sea Level Variations ◽  
The North Atlantic ◽  
Depth Inference ◽  
Mass Component

Rapid sea-level rise in the North Atlantic Ocean since the first half of the nineteenth century

The Holocene ◽  
2006 ◽  
Vol 16 (7) ◽  
pp. 949-965 ◽  
Author(s):  
W. Roland Gehrels ◽  
William A. Marshall ◽  
Maria J. Gehrels ◽  
Gudrún Larsen ◽  
Jason R. Kirby ◽  
...  
Keyword(s):  
Nineteenth Century ◽  
Atlantic Ocean ◽  
Sea Level Rise ◽  
Sea Level ◽  
North Atlantic ◽  
North Atlantic Ocean ◽  
The North ◽  
The North Atlantic

Observations of the 18.6-year cycle effects on the sea-level oscillations in the North Atlantic Ocean

2012 ◽  
Vol 100 (3) ◽  
pp. 39003 ◽  
Author(s):  
P. Capuano ◽  
E. De Lauro ◽  
S. De Martino ◽  
M. Falanga
Keyword(s):  
Atlantic Ocean ◽  
Sea Level ◽  
North Atlantic ◽  
North Atlantic Ocean ◽  
The North ◽  
Sea Level Oscillations ◽  
The North Atlantic

Earthquakes induced by ice-mass loss: A case example for southern Greenland

2021 ◽  
Author(s):  
Rebekka Steffen ◽  
Holger Steffen ◽  
Robert Weiss ◽  
Benoit Lecavalier ◽  
Glenn Milne ◽  
...  
Keyword(s):  
Atlantic Ocean ◽  
Mass Loss ◽  
Sea Level ◽  
North Atlantic ◽  
North Atlantic Ocean ◽  
Greenland Ice Sheet ◽  
Large Mass ◽  
Large Magnitude ◽  
The North ◽  
The North Atlantic

<p>Due to their large mass, ice sheets induce significant stresses in the Earth’s crust. Stress release during deglaciation can trigger large-magnitude earthquakes, as indicated by surface faults in northern Europe. Thus, the current ice-mass loss in Greenland can be accompanied by earthquakes. Here, we will present an example of a possible large magnitude earthquake that occurred during the large melting period of the Greenland Ice Sheet in the early Holocene. The glacially induced stresses showed an instability occurring at 10,600 years ago. An offset in past sea level indicators falls within the same time frame, which gave us indications that the stresses have been released by an earthquake. The potential fault could have slipped up to 47 m, resulting in a large magnitude earthquake, if only one event occurred. The earthquake may have shifted relative sea level observations by several meters. In addition, as the potential fault is located offshore, the earthquake could have produced a tsunami in the North Atlantic Ocean with runup heights of up to 7.2 m in the British Isles and up to 7.8 m along Canadian coasts. Thus, ice-mass loss is strongly linked to the occurrence of earthquakes and even earthquakes-related tsunami. These scenarios due to a changing cryosphere can have effects for all countries bordering the North Atlantic Ocean and are in addition to the well-known sea-level rise.</p>

Seismic stratigraphy of the Vendean-Armorican platform of the French Atlantic shelf: new insights into the history of the North Atlantic ocean

2010 ◽  
Vol 181 (1) ◽  
pp. 37-50
Author(s):  
Pedro Huerta ◽  
Jean-Noël Proust ◽  
Pol Guennoc ◽  
Isabelle Thinon
Keyword(s):  
High Resolution ◽  
Atlantic Ocean ◽  
Sea Level ◽  
North Atlantic ◽  
North Atlantic Ocean ◽  
Passive Margin ◽  
Tectonic Activity ◽  
Marine Deposits ◽  
The North ◽  
The North Atlantic

Abstract The evolution of the North-Atlantic Ocean from its rifting stage during the Upper Jurassic until the present-day passive margin is recorded by the sedimentary wedge of eastern French-Atlantic platform. The study of a dense network of high resolution seismic profiles on the Vendean-Armorican platform (VAP) obtained during INSU-CNRS cruise “Geovend”, led to the characterization of the architecture of the sediment wedge preserved between the coast and Armorican margin shelf edge. This sediment wedge lies on a substratum composed of metamorphic and magmatic rocks of Palaeozoic age (Ub). The sediment wedge comprises six seismic units (U1-U6) bounded by regional unconformities: Jurassic marine succession (U1), Upper Cretaceous marine rocks (U2), Eocene-Oligocene marine deposits of the incipient VAP (U3), Miocene (U4) and Plio-Quaternary (U5) marine deposits overlain by the last sea-level rise ravinement deposits (U6). Above the basal unconformity at the top of Ub, the units are bounded by angular unconformities (top of U1, U2, U3), truncation with channel incision (top U4) or planar marine ravinement (top of U5) surfaces. Most of these unconformities are due to the tectonic activity of the bay of Biscay during the Mesozoic including (1) the North Atlantic rifting during the Jurassic to Early Cretaceous, (2) the propagation of the ocean crust and counterclockwise rotation of the Iberian block during the Aptian-Albian to Coniacian (magnetic anomaly 33–34) producing troughs at the top of U1 filled by downlapping U2 sediment wedges, (3) the Alpine compression at the origin of folding and faulting and the unconformable deposition of U3, and (4) the late compressive deformation during the Miocene that affected U4. The VAP acquires its actual configuration during U4. Sedimentation on the platform was then affected by climatically-controlled relative sea-level changes (U5 to U6) that forced U5 shelf margin sediment deposition above an incised unconformity and subsequently overlain by U6 transgressive sediment blanketing. One of the main interest of the VAP area is the existence of pre- to post-rift units that helps to decipher with high resolution seismics the long-lived evolution of the Armorican margin. Such units are preserved because of the specific characters of this area located on the flank of the former Aquitaine basin (near the “celtaquitaine” flexure) and the presence of the Rochebonne basement high. The VAP thus displays most of the tectonosedimentary evolution of the West Atlantic margins. This paper would however constitute a basis for comparisons to other examples around the Atlantic ocean and then contribute to strengthen the running models of passive margin evolution.

scholarly journals Sub-basin-scale sea level budgets from satellite altimetry, Argo floats and satellite gravimetry: a case study in the North Atlantic Ocean

Ocean Science ◽  
2016 ◽  
Vol 12 (6) ◽  
pp. 1179-1203 ◽  
Author(s):  
Marcel Kleinherenbrink ◽  
Riccardo Riva ◽  
Yu Sun
Keyword(s):  
Atlantic Ocean ◽  
Sea Level ◽  
North Atlantic ◽  
North Atlantic Ocean ◽  
Covariance Matrices ◽  
Sea Levels ◽  
The North ◽  
Basin Scale ◽  
Gravity Fields ◽  
The North Atlantic

Abstract. In this study, for the first time, an attempt is made to close the sea level budget on a sub-basin scale in terms of trend and amplitude of the annual cycle. We also compare the residual time series after removing the trend, the semiannual and the annual signals. To obtain errors for altimetry and Argo, full variance–covariance matrices are computed using correlation functions and their errors are fully propagated. For altimetry, we apply a geographically dependent intermission bias [Ablain et al.(2015)], which leads to differences in trends up to 0.8 mm yr−1. Since Argo float measurements are non-homogeneously spaced, steric sea levels are first objectively interpolated onto a grid before averaging. For the Gravity Recovery And Climate Experiment (GRACE), gravity fields full variance–covariance matrices are used to propagate errors and statistically filter the gravity fields. We use four different filtered gravity field solutions and determine which post-processing strategy is best for budget closure. As a reference, the standard 96 degree Dense Decorrelation Kernel-5 (DDK5)-filtered Center for Space Research (CSR) solution is used to compute the mass component (MC). A comparison is made with two anisotropic Wiener-filtered CSR solutions up to degree and order 60 and 96 and a Wiener-filtered 90 degree ITSG solution. Budgets are computed for 10 polygons in the North Atlantic Ocean, defined in a way that the error on the trend of the MC plus steric sea level remains within 1 mm yr−1. Using the anisotropic Wiener filter on CSR gravity fields expanded up to spherical harmonic degree 96, it is possible to close the sea level budget in 9 of 10 sub-basins in terms of trend. Wiener-filtered Institute of Theoretical geodesy and Satellite Geodesy (ITSG) and the standard DDK5-filtered CSR solutions also close the trend budget if a glacial isostatic adjustment (GIA) correction error of 10–20 % is applied; however, the performance of the DDK5-filtered solution strongly depends on the orientation of the polygon due to residual striping. In 7 of 10 sub-basins, the budget of the annual cycle is closed, using the DDK5-filtered CSR or the Wiener-filtered ITSG solutions. The Wiener-filtered 60 and 96 degree CSR solutions, in combination with Argo, lack amplitude and suffer from what appears to be hydrological leakage in the Amazon and Sahel regions. After reducing the trend, the semiannual and the annual signals, 24–53 % of the residual variance in altimetry-derived sea level time series is explained by the combination of Argo steric sea levels and the Wiener-filtered ITSG MC. Based on this, we believe that the best overall solution for the MC of the sub-basin-scale budgets is the Wiener-filtered ITSG gravity fields. The interannual variability is primarily a steric signal in the North Atlantic Ocean, so for this the choice of filter and gravity field solution is not really significant.

Sign in / Sign up

Export Citation Format

Share Document