Sea level and the southern oscillation

Sea level and the southern oscillation

Oceanographic Abstracts 41 climatic advances (interglacial). The critical Mediterranean barrier lay squarely across migration routes of the old worl...

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Oceanographic Abstracts

41

climatic advances (interglacial). The critical Mediterranean barrier lay squarely across migration routes of the old world. The Quaternary eustatic reconstruction suggests, but that, even at cold maxima, sea level was never below the present before the Mindel, after this it did drop (to ca. -- 100 m) in the Kiss and Wfirm, the last with double minima. The eustatic changes were not of sufficient amplitude to permit ' land b r i d g e ' migrations at Gibraltar or Sicily; only Thrace and north o f the Black Sea offered suitable routes. In the geological complexity of the Mediterranean engendered by local crustal movements, the eustatic-climatic approach aided by isotopic analyses should go far in helping to unravel the confusing stratigraphy. FAIRBRtDGE, R. W. a n d O. A. KR~ns, JR., 1962. Sea level and the southern oscillation. Geophys.

J., Roy. Astron. Soc., 6 (4): 532-545. An average curve for the world annual mean sea level for the century 1860-1960 has been obtained from a carefully selected world series of tide gauge records. We have eliminated data from tectonically unstable areas and other obviously anomalous records. Five year running means provide us with a residual curve that may approach a eustatic standard (propably glacio-eustatic). The lowest point of sea level was about 1890; the mean rise from 1900-1950 was 1.2 m m annually, but the fastest decade was 1946--1956 with 5.5 mm. The pattern varies somewhat if plotted ocean by ocean. The non-smoothed, annual curve shows a 2-3 yr cyclicity of 10-30 m m amplitude. For the world curve this periodicity resembles the 2-3 yr atmospheric pressure cycle known as the 'Southern Oscillation,' being in phase with the S.E. Pacific node. The reciprocal, Indian Ocean node is well reflected in the Indian Ocean, and periodically dominates over the Pacific pattern in the Atlantic Ocean. When the effect of a pressure anomaly of 1 m b is taken as equivalent to 10 m m departure of sea level, it is found that that is still a large residual generally in the same phase. It would seem that steric effects and associated wind systems are mainly responsible.

FEDOTOV,S. A. and I. P. KUZIN, 1963. The velocity profile of the upper mantle in the vicinity of the South Kuril Islands. Izv. Akad. Nauk, SSSR, Set. Geofiz., (5): 670--688. Eng. Transl.: Amer. Geophys. Union, (5): 415--425. The procedure for determining the velocity profile of the upper mantle by Kiznichenko's method of theoretical travel-time curves has been further developed. A velocity profile of the upper mantle has been constructed for the south of the Kuril Island are. A wave guide has not been detected. FLEMING,C. A., 1963. A moa-bone from the sea-floor in Cook Strait. Rec. Dom. Mus., N.Z., 4 (16): 231-233. A n imperfect tibia of Anomalopteryx oweni (Haast) (?), trawled from 50 fms off Kapiti Island, is thought to be the first fossil record of a terrestrial animal on the New Zealand continental shelf, an area that was probably land in at least some of the glacial stages of the Pleistocene. FOg~ST, J., 1961. Pagurides de l'Afriqtm occidentale. Atlantide Rep. 6: 203-250. The collection comprises 700 specimens and forty-five species (75 per cent of all species known from the area), recorded from a large number of localities. The regional or bathymetric distribution of many species if greatly extended, Diogenes ortholepsis a n d Anapagurus wolffi arc described as new, and Eupagurus? mimimus Chevreux and Bouvier, 1892 is redescribexi and referred to Paguridum nov. gen.

FOREST, J., 1963. Sur deux Scyllarus de l'Atlantique tropical africain: S. paradoxus Miers et S. posteli sp. nov. Remarques sur les $cyllarus de l'Atlantique oriental. Bull. Inst. Ocdan., Monaco, 60 (1259): 20 pp. The study of a collection of west African Scyllarus has shown that specimens referred to as S. paradoxus by several authors do not agree with the form originally designated ' Scyllarus (Arctus) arctus var. paradoxus" by Miers. These specimens belong to a species described here as S. posteli nov. sp. The collection examined also includes material of the true S. paradoxus, the determination having been confirmed by comparison with Miers' type specimen. The two species are related although they differ in a number o f characters. The identity of post-larvae attributed to S. paradoxus remains doubtful; it is possible that some of them are referable to S. caparti Holthuis, the third west African species. S. p~adoxus Miers and S. posteli nov. sp. are also compared with S. arctus (Linn6) and S. pygnaeus (Bate), two other species from the eastern Atlantic. As far as is known at present, the Scyllarus of this region are divisible into two clearly separated geographical groups. S. paradoxus, S. posteli and S. caparti, known from D a k a r to the Congo, are exclusively tropical. S. arctus a n d S. pygmaeus both occur in the Mediterranean, at Madeira and at the Canaries; but the first, more northern, reaches the coast of Britain, and the second, more southern, the Cape Verde Islands.