Forcing of coastal sea level rise patterns in the North Atlantic and the Mediterranean Sea

The Mediterranean Sea can be viewed as a “barometer” of the North Atlantic Ocean, because its sea level responds to oceanic-gyre-scale changes in atmospheric pressure and wind forcing, related to the North Atlantic Oscillation (NAO). The climate of the North Atlantic is influenced by the Atlantic meridional overturning circulation (AMOC) as it transports heat from the South Atlantic toward the subpolar North Atlantic. This study reports on a teleconnection between the AMOC transport measured at 26.5°N and the Mediterranean Sea level during 2004–17: a reduced/increased AMOC transport is associated with a higher/lower sea level in the Mediterranean. Processes responsible for this teleconnection are analyzed in detail using available satellite and in situ observations and an atmospheric reanalysis. First, it is shown that on monthly to interannual time scales the AMOC and sea level are both driven by similar NAO-like atmospheric circulation patterns. During a positive/negative NAO state, stronger/weaker trade winds (i) drive northward/southward anomalies of Ekman transport across 26.5°N that directly affect the AMOC and (ii) are associated with westward/eastward winds over the Strait of Gibraltar that force water to flow out of/into the Mediterranean Sea and thus change its average sea level. Second, it is demonstrated that interannual changes in the AMOC transport can lead to thermosteric sea level anomalies near the North Atlantic eastern boundary. These anomalies can (i) reach the Strait of Gibraltar and cause sea level changes in the Mediterranean Sea and (ii) represent a mechanism for negative feedback on the AMOC.

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Last Ice Age Millennial Scale Climate Changes Recorded in Huon Peninsula Corals

Radiocarbon ◽

10.1017/s0033822200030320 ◽

2000 ◽

Vol 42 (3) ◽

pp. 383-401 ◽

Cited By ~ 63

Author(s):

Yusuke Yokoyama ◽

Tezer M Esat ◽

Kurt Lambeck ◽

L Keith Fifield

Keyword(s):

Sea Level Rise ◽

Sea Level ◽

North Atlantic ◽

Thermohaline Circulation ◽

Sample Selection ◽

Ice Age ◽

Base Line ◽

The North ◽

Sequence Of Events ◽

The North Atlantic

Uranium series and radiocarbon ages were measured in corals from the uplifted coral terraces of Huon Peninsula (HP), Papua New Guinea, to provide a calibration for the 14C time scale beyond 30 ka (kilo annum). Improved analytical procedures, and quantitative criteria for sample selection, helped discriminate diagenetically altered samples. The base-line of the calibration curve follows the trend of increasing divergence from calendar ages, as established by previous studies. Superimposed on this trend, four well-defined peaks of excess atmospheric radiocarbon were found ranging in magnitude from 100% to 700%, relative to current levels. They are related to episodes of sea-level rise and reef growth at HP. These peaks appear to be synchronous with Heinrich Events and concentrations of ice-rafted debris found in North Atlantic deep-sea cores. Relative timing of sea-level rise and atmospheric 14C excess imply the following sequence of events: An initial sea-level high is followed by a large increase in atmospheric 14C as the sea-level subsides. Over about 1800 years, the atmospheric radiocarbon drops to below present ambient levels. This cycle bears a close resemblance to ice-calving episodes of Dansgaard-Oeschger and Bond cycles and the slow-down or complete interruption of the North Atlantic thermohaline circulation. The increases in the atmospheric 14C levels are attributed to the cessation of the North Atlantic circulation.

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The reproductive biology of swordfish (Xiphias gladius) in the Strait of Gibraltar

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315418000346 ◽

2018 ◽

Vol 99 (3) ◽

pp. 649-659 ◽

Cited By ~ 5

Author(s):

Noureddine Abid ◽

Amin Laglaoui ◽

Abdelhay Arakrak ◽

Mohammed Bakkali

Keyword(s):

Mediterranean Sea ◽

North Atlantic ◽

Fork Length ◽

Strait Of Gibraltar ◽

Mixing Rate ◽

The North ◽

Lower Jaw ◽

The North Atlantic ◽

The Mediterranean ◽

First Maturity

During the period from April to September for the years 2014–2016, 998 swordfishes caught by the Moroccan artisanal longline fishery in the Strait of Gibraltar were sampled to study the reproduction of this species in this mixing area between the Mediterranean Sea and the North Atlantic. The results showed that the sex ratio is slightly in favour of males for sizes smaller than 130 cm LJFL (Lower jaw-fork length), whereas females are more numerous in sizes larger than 140 cm LJFL. Fifty per cent of females were estimated to be mature at 170 cm LJFL, while for males, the size at first maturity was estimated to be 95 cm LJFL. The swordfish spawn from June to September, probably in the Mediterranean Sea. The findings of this study suggest that the reproductive characteristics of swordfish caught in the Strait of Gibraltar are similar to those of the Mediterranean swordfish, and a high mixing rate between the Mediterranean and the North Atlantic stocks occurs in the study area.

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Messinian deep-water turbidites and glacioeustatic sea-level changes in the North Atlantic: Linkage to the Mediterranean salinity crisis

Paleoceanography ◽

10.1029/96pa00572 ◽

1996 ◽

Vol 11 (3) ◽

pp. 277-297 ◽

Cited By ~ 12

Author(s):

Jijun Zhang ◽

David B. Scott

Keyword(s):

Sea Level ◽

North Atlantic ◽

Deep Water ◽

Sea Level Changes ◽

The North ◽

The North Atlantic ◽

The Mediterranean

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Sailing Directions of the North Atlantic Viking Age (from about the year 860 to 1400)

Journal of Navigation ◽

10.1017/s0373463300023584 ◽

1997 ◽

Vol 50 (1) ◽

pp. 55-64 ◽

Cited By ~ 5

Author(s):

Søren Thirslund

Keyword(s):

Mediterranean Sea ◽

Fresh Water ◽

North Atlantic ◽

Western Europe ◽

Viking Age ◽

The North ◽

The World ◽

The North Atlantic ◽

The Mediterranean ◽

New Settlements

As long as man has ventured to go to sea, sailing directions have existed. Man's survival depended upon knowing the best fishing and hunting places and how to find these were secrets, told only to family or friends.Later, sailing directions covered areas in the world where trade or new settlements had begun and, as early as 500 years B.C., some of these sailing directions were written down. They covered the Mediterranean Sea and part of western Europe and they were called PERIPLUS meaning ‘sailing around’. They contained almost the same information as sailing directions today, namely: harbours, anchorages, currents, possibilities for fresh water, provisions and other supplies.

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