Distribution of icebergs in the pacific ocean sector of the southern ocean, based on observations from the icebreakerVladivostok

Mesosignum weddellensis sp. nov. is described from the abyssal Weddell Sea, Antarctica. This is the second record of Mesosignum from the Southern Ocean, the other known species being M. antarcticum Schultz, 1979. Mesosignum brevispinis Birstein, 1963 from the Pacific Ocean is the most similar species. The most significant difference is the length of the seventh pereonite, which is only half as long as the other pereonites in M. brevispinis, while in M. weddellensis it is as long as the other pereonites.

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The Relationship between Wave Trains in the Southern Hemisphere Storm Track and Rainfall Extremes over Tasmania

Monthly Weather Review ◽

10.1175/mwr-d-18-0135.1 ◽

2018 ◽

Vol 146 (12) ◽

pp. 4201-4230 ◽

Cited By ~ 7

Author(s):

Carly R. Tozer ◽

James S. Risbey ◽

Terence J. O’Kane ◽

Didier P. Monselesan ◽

Michael J. Pook

Keyword(s):

Pacific Ocean ◽

Indian Ocean ◽

Wave Train ◽

Storm Track ◽

The Pacific ◽

Rainfall Extremes ◽

The Indian Ocean ◽

The Pacific Ocean ◽

Wave Trains ◽

Ocean Sector

Abstract We assess the large-scale atmospheric dynamics influencing rainfall extremes in Tasmania, located within the Southern Hemisphere storm track. We characterize wet and dry multiday rainfall extremes in western and eastern Tasmania, two distinct climate regimes, and construct atmospheric flow composites around these extreme events. We consider the onset and decay of the events and find a link between Rossby wave trains propagating in the polar jet waveguide and wet and dry extremes across Tasmania. Of note is that the wave trains exhibit varying behavior during the different extremes. In the onset phase of rainfall extremes in western Tasmania, there is a coherent wave train in the Indian Ocean, which becomes circumglobal in extent and quasi-stationary as the event establishes and persists. Wet and dry extremes in this region are influenced by opposite phases of this circumglobal wave train pattern. In eastern Tasmania, wet extremes relate to a propagating wave train, which is first established in the Indian Ocean sector and propagates eastward to the Pacific Ocean sector as the event progresses. During dry extremes in eastern Tasmania, the wave train is first established in the Pacific Ocean, as opposed to Indian Ocean, and persists in this sector for the entire event, with a structure indicative of the Pacific–South American pattern. The findings regarding different wave train forms and their relationship to rainfall extremes have implications for extreme event attribution in other regions around the globe.

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Seasonal and Interannual Variability of the Indo-Pacific Warm Pool and its Associated Climate Factors Based on Remote Sensing

Remote Sensing ◽

10.3390/rs12071062 ◽

2020 ◽

Vol 12 (7) ◽

pp. 1062 ◽

Cited By ~ 2

Author(s):

Zi Yin ◽

Qing Dong ◽

Fanping Kong ◽

Dan Cao ◽

Shuang Long

Keyword(s):

Pacific Ocean ◽

Indian Ocean ◽

Time Scale ◽

Warm Pool ◽

Ocean Basin ◽

The Pacific ◽

Pacific Warm Pool ◽

The Indian Ocean ◽

The Pacific Ocean ◽

Ocean Sector

With satellite observed Sea Surface Temperature (SST) accumulated for multiple decades, multi-time scale variabilities of the Indo-Pacific Warm Pool are examined and contrasted in this study by separating it into the Indian Ocean sector and the Pacific Ocean sector. Surface size, zonal center, meridional center, maximum SST and mean SST as the practical warm pool properties are chosen to investigate the warm pool variations for the period 1982–2018. On the seasonal time scale, the oscillation of the Indian Warm Pool is found much more vigorous than the Pacific Warm Pool on size and intensity, yet the interannual variabilities of the Indian Warm Pool and the Pacific Warm Pool are comparable. The Indian Warm Pool has weak interannual variations (3–5 years) and the Pacific Warm Pool has mighty interdecadal variations. The size, zonal movement and mean SST of the Indian Ocean Warm Pool (IW) are more accurate to depict the seasonal variability, and for the Pacific Ocean Warm Pool (PW), the size, zonal and meridional movements and maximum SST are more suitable. On the interannual scale, except for the meridional movements, all the other properties of the same basin have similar interannual variation signals. Following the correlation analysis, it turns out that the Indian Ocean basin-wide index (IOBW) is the most important contributor to the variabilities of both sectors. Lead-lag correlation results show that variation of the Pacific Ocean Warm Pool leads the IOBW and variation of the Indian Ocean Warm Pool is synchronous with the IOBW. This indicates that both sectors of the Indo-Pacific Warm Pool are significantly correlated with basin-wide warming or cooling.

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Kelvin Waves around Antarctica

Journal of Physical Oceanography ◽

10.1175/jpo-d-14-0051.1 ◽

2014 ◽

Vol 44 (11) ◽

pp. 2909-2920 ◽

Cited By ~ 11

Author(s):

Kazuya Kusahara ◽

Kay I. Ohshima

Keyword(s):

Pacific Ocean ◽

Southern Ocean ◽

Sea Level ◽

Statistical Significance ◽

Phase Speed ◽

Drake Passage ◽

Kelvin Waves ◽

The Pacific ◽

The Pacific Ocean ◽

The Antarctic

Abstract The Southern Ocean allows circumpolar structure and the Antarctic coastline plays a role as a waveguide for oceanic Kelvin waves. Under the cyclic conditions, the horizontal wavenumbers and frequencies for circumpolarly propagating waves are quantized, with horizontal wavenumbers 1, 2, and 3, corresponding to periods of about 32, 16, and 11 h, respectively. At these frequencies, westward-propagating signals are detected in sea level variation observed at Antarctic coastal stations. The occurrence frequency of westward-propagating signals far exceeds the statistical significance, and the phase speed of the observed signal agrees well with the theoretical phase speed of external Kelvin waves. Therefore, this study concludes that the observed, westward-propagating sea level variability is a signal of the external Kelvin waves of wavenumbers 1, 2, and 3 around Antarctica. A series of numerical model experiments confirms that Kelvin waves around Antarctica are driven by surface air pressure and that these waves are excited not only by local forcing over the Southern Ocean, but also by remote forcing over the Pacific Ocean. Sea level variations generated over the Pacific Ocean can travel to the western side of the South American coast and cross over Drake Passage to the Antarctic continent, constituting a part of the Kelvin waves around Antarctica.

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Interactive comment on “Analysis of geomagnetic measurements prior the Maule (2010), Iquique (2014) and Illapel (2015) earthquakes, in the Pacific Ocean sector of the Southern Hemisphere” by Enrique G. Cordaro et al.

10.5194/angeo-2019-9-ac1 ◽

2019 ◽

Author(s):

Enrique Cordaro

Keyword(s):

Pacific Ocean ◽

Southern Hemisphere ◽

The Pacific ◽

The Pacific Ocean ◽

Ocean Sector ◽

Geomagnetic Measurements

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Two new subscpecies of Antarctic horsefish (Zanclorhynchus, Scorpaeniformes: Congiopodidae) from Indian Sector of Southern Ocean

Proceedings of the Zoological Institute RAS ◽

10.31610/trudyzin/2019.323.4.541 ◽

2019 ◽

Vol 323 (4) ◽

pp. 541-557

Author(s):

M.Yu. Zhukov

Keyword(s):

Southern Ocean ◽

Demersal Fish ◽

Individual Variability ◽

Prince Edward Islands ◽

The Pacific ◽

Subantarctic Islands ◽

Infraorbital Canal ◽

The Pacific Ocean ◽

Ocean Sector ◽

Indian Sector

The goal of this work is to revise the endemic South Ocean species Zanclorhynchus spinifer, one of the most numerous demersal fish species inhabiting waters off subantarctic islands. Despite its high abundance and significant role in trophic chains, the species remained poorly described. Morphological parameters were studied for the first time on a significant amount of material; individual variability was clarified for a number of parameters. Such variability, according to some characteristics, is beyond the range of values previously used in the description of the species, and the occurring break of the infraorbital canal was previously considered to be characteristic in the family Congiopodidae only for the sister genus Alertichthys. The two new subscpecies Zanclorhynchus spinifer armatus subsp. nov and Z. spinifer macquariensis subsp. nov. are described in this paper in addition to the nominative subspecies and the previously described subspecies from the seamounts of the Pacific Ocean sector of the Southern Ocean Z. spinifer heracleus. Type series were collected in the Indian sector of Southern Ocean off the Prince Edward Islands and the Crozet Islands from the depth 170–310 metres, and off the Macquarie Island from the depth 21–84 meters. New subscpecies well differs from other two subcpecies Z. spinifer spinifer and Z. spinifer heracleus with arming of the head and first dorsal fin, scales and body proportions. A key to the species and subspecies of the genus Zanclorhynchus is presented.

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A skill assessment of the biogeochemical model REcoM2 coupled to the Finite Element Sea Ice–Ocean Model (FESOM 1.3)

Geoscientific Model Development ◽

10.5194/gmd-7-2769-2014 ◽

2014 ◽

Vol 7 (6) ◽

pp. 2769-2802 ◽

Cited By ~ 10

Author(s):

V. Schourup-Kristensen ◽

D. Sidorenko ◽

D. A. Wolf-Gladrow ◽

C. Völker

Keyword(s):

Finite Element ◽

Pacific Ocean ◽

Southern Ocean ◽

Sea Ice ◽

Chlorophyll A ◽

Ocean Model ◽

Biogeochemical Model ◽

Export Production ◽

The Pacific ◽

The Pacific Ocean

Abstract. In coupled biogeochmical–ocean models, the choice of numerical schemes in the ocean circulation component can have a large influence on the distribution of the biological tracers. Biogeochemical models are traditionally coupled to ocean general circulation models (OGCMs), which are based on dynamical cores employing quasi-regular meshes, and therefore utilize limited spatial resolution in a global setting. An alternative approach is to use an unstructured-mesh ocean model, which allows variable mesh resolution. Here, we present initial results of a coupling between the Finite Element Sea Ice–Ocean Model (FESOM) and the biogeochemical model REcoM2 (Regulated Ecosystem Model 2), with special focus on the Southern Ocean. Surface fields of nutrients, chlorophyll a and net primary production (NPP) were compared to available data sets with a focus on spatial distribution and seasonal cycle. The model produces realistic spatial distributions, especially regarding NPP and chlorophyll a, whereas the iron concentration becomes too low in the Pacific Ocean. The modelled NPP is 32.5 Pg C yr−1 and the export production 6.1 Pg C yr−1, which is lower than satellite-based estimates, mainly due to excessive iron limitation in the Pacific along with too little coastal production. The model performs well in the Southern Ocean, though the assessment here is hindered by the lower availability of observations. The modelled NPP is 3.1 Pg C yr−1 in the Southern Ocean and the export production 1.1 Pg C yr−1. All in all, the combination of a circulation model on an unstructured grid with a biogeochemical–ocean model shows similar performance to other models at non-eddy-permitting resolution. It is well suited for studies of the Southern Ocean, but on the global scale deficiencies in the Pacific Ocean would have to be taken into account.

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