Foraminiferal tracers of Indian-Atlantic interocean exchange during the last 600 kyr

2020 ◽  
Author(s):  
José N. Pérez-Asensio ◽  
Kazuyo Tachikawa ◽  
Thibault de Garidel-Thoron ◽  
Laurence Vidal ◽  
Corinne Sonzogni ◽  
...  
Keyword(s):  
Indian Ocean ◽  
Atlantic Ocean ◽  
Deep Water ◽  
Water Circulation ◽  
Warm Water ◽  
Temperate Climate ◽  
Agulhas Current ◽  
Foraminiferal Species ◽  
The Indian Ocean ◽  
Relative Abundances

<p>The Indian-Atlantic interocean exchange (IAIE), occurring through Agulhas current and its leakage around the southern tip of Africa, is one of the return flows of global thermohaline circulation that contributes to the temperate climate in Europe. The IAIE affects the transport of heat and salt to the zone of deep-water formation in the N Atlantic, influencing the variability of Atlantic Meridional Overturning Circulation (AMOC). During the last 600 kyr, significant climatic events took place such as the Mid-Bruhnes event (MBE) (~430 ka) that marks a transition towards more intense interglacial periods.</p><p>The main objective of our study is to assess the impact of climate forcing on the strength of both surface and deep water IAIE during the last 600 kyr. For this purpose, we examined the variability of a group of warm-water planktonic foraminiferal species for tracing surface water circulation. We combined published and unpublished data from 3 cores along an Indian-Atlantic transect: two cores in the Indian Ocean, core MD96-2048 (26°10’S, 34°01’E, 660 m) in the source of the Agulhas current and our study core MD96-2077 (33º10’S, 31º14’E, 3781 m) in the middle of the Agulhas current; and one core in the Atlantic Ocean, core ODP1087 (31°27’S, 15°18’E 1372 m) recording the Agulhas leakage.</p><p>Since <em>Globorotalia menardii</em> and <em>Globorotalia tumida</em> are frequently used to trace Agulhas leakage, their variability in Agulhas current in the Indian Ocean is of our interest. Therefore, we compared the relative abundances of the warm-water planktonic <em>G. menardii</em> and <em>G. tumida</em> species with a group of warm-water planktonic foraminiferal species to record the strength of Agulhas current in core MD96-2077. Our results show that the group of warm-water planktonic species reflects increased Agulhas current strength at glacial terminations coinciding with stronger Agulhas leakage (Atlantic core ODP1087) as observed in previous studies. However, in core MD96-2077, both <em>G. menardii</em> and <em>G. tumida</em> relative abundances increase during interglacial periods. This indicates that production of these species in the Agulhas current source region is unlikely to trace Agulhas leakage in the Atlantic Ocean. The analyses of deep-water circulation proxies (Nd isotopes, benthic O and C stable isotopes) are in progress, and they will allow us to assess the response of deep circulation to changes in Agulhas current and leakage over the last 600 kyr.</p>

scholarly journals The Deep-Water Circulation of the Indian Ocean

Nature ◽  
1935 ◽  
Vol 136 (3450) ◽  
pp. 936-938 ◽  
Author(s):  
A. J. Clowes ◽  
G. E. R. Deacon
Keyword(s):  
Indian Ocean ◽  
Deep Water ◽  
Water Circulation ◽  
The Indian Ocean

scholarly journals Research Gap Analysis of Remote Sensing Application in Fisheries: Prospects for Achieving the Sustainable Development Goals

2021 ◽  
Vol 13 (5) ◽  
pp. 1013
Author(s):  
Kuo-Wei Yen ◽  
Chia-Hsiang Chen
Keyword(s):  
Sustainable Development ◽  
Indian Ocean ◽  
Atlantic Ocean ◽  
The Sustainable Development ◽  
The North ◽  
The Pacific ◽  
Development Goals ◽  
The Indian Ocean ◽  
The Pacific Ocean ◽  
Research Hotspots

Remote sensing (RS) technology, which can facilitate the sustainable management and development of fisheries, is easily accessible and exhibits high performance. It only requires the collection of sufficient information, establishment of databases and input of human and capital resources for analysis. However, many countries are unable to effectively ensure the sustainable development of marine fisheries due to technological limitations. The main challenge is the gap in the conditions for sustainable development between developed and developing countries. Therefore, this study applied the Web of Science database and geographic information systems to analyze the gaps in fisheries science in various countries over the past 10 years. Most studies have been conducted in the offshore marine areas of the northeastern United States of America. In addition, all research hotspots were located in the Northern Hemisphere, indicating a lack of relevant studies from the Southern Hemisphere. This study also found that research hotspots of satellite RS applications in fisheries were mainly conducted in (1) the northeastern sea area in the United States, (2) the high seas area of the North Atlantic Ocean, (3) the surrounding sea areas of France, Spain and Portugal, (4) the surrounding areas of the Indian Ocean and (5) the East China Sea, Yellow Sea and Bohai Bay sea areas to the north of Taiwan. A comparison of publications examining the three major oceans indicated that the Atlantic Ocean was the most extensively studied in terms of RS applications in fisheries, followed by the Indian Ocean, while the Pacific Ocean was less studied than the aforementioned two regions. In addition, all research hotspots were located in the Northern Hemisphere, indicating a lack of relevant studies from the Southern Hemisphere. The Atlantic Ocean and the Indian Ocean have been the subjects of many local in-depth studies; in the Pacific Ocean, the coastal areas have been abundantly investigated, while offshore local areas have only been sporadically addressed. Collaboration and partnership constitute an efficient approach for transferring skills and technology across countries. For the achievement of the sustainable development goals (SDGs) by 2030, research networks can be expanded to mitigate the research gaps and improve the sustainability of marine fisheries resources.

Art. VII.—Notes on Persian Belúchistán. From the Persian of Mirza Mehdy Khán. Published Teheran, July, 1875

1876 ◽  
Vol 9 (1) ◽  
pp. 147-154
Author(s):  
A. H. Schindler
Keyword(s):  
Indian Ocean ◽  
Temperate Climate ◽  
The South ◽  
The West ◽  
The North ◽  
The People ◽  
The Indian Ocean ◽  
The Hill ◽  
Cool Climate

The part of Belúchistán now under Persian rule is bounded upon the north by Seistán, upon the east by Panjgúr and Kej, upon the south by the Indian Ocean, and upon the west by Núrámshír, Rúdbár, and the Báshákerd mountains.This country enjoys a variety of climates; almost unbearable heat exists on the Mekrán coast, we find a temperate climate on the hill slopes and on the slightly raised plains as at Duzek and Bampúr, and a cool climate in the mountainous districts Serhad and Bazmán. The heat at Jálq is said to be so intense in summer that the gazelles lie down exhausted in the plains, and let themselves be taken by the people without any trouble.

scholarly journals Global epidemiology of Zika and Chikungunya virus human infections

2017 ◽  
Vol 32 (3) ◽  
Author(s):  
Silvia Zannoli ◽  
Manuela Morotti ◽  
Agnese Denicolò ◽  
Martina Tassinari ◽  
Claudia Chiesa ◽  
...  
Keyword(s):  
Indian Ocean ◽  
Sexual Transmission ◽  
Human Infection ◽  
Temperate Climate ◽  
Global Epidemiology ◽  
Large Outbreak ◽  
The Usa ◽  
Sporadic Cases ◽  
The Indian Ocean ◽  
Human Infections

Zika virus was discovered in 1947. The first reported case of Zika fever was in a sentinel rhesus monkey in Uganda in 1947, while the first human cases were reported in Nigeria in 1954. Since the first evidence of human infection, Zika was active in several countries in Africa and Asia, as sporadic cases and serological evidence of Zika human infections have been demonstrated in several reports. The outbreak of Zika in Yap Island in 2007 is considered the first emergency of this infection. Since then Zika has spread worldwide with a large ongoing epidemic in South and Central America. A huge concern nowadays is about the relationship between Zika infection and microcephaly and about the sexual transmission of the virus. The first identified outbreak of Chikungunya human infection, with an incidence estimated at 23%, was reported from July 1952 to March 1953 in the Southern Province of the current Tanzania. Since then Chikungunya circulated mainly in continental Africa with limited outbreaks. The virus started to spread east bound involving most of the areas surroundings the Indian Ocean. In 2004/2005 a large outbreak developed in La Reunion a French territory in the Indian Ocean: from this point Chikungunya spread to India and from there, due a viraemic traveller returning from Kerala, to Italy where in the summer of 2007 the first outbreak with local viral transmission in a temperate climate zone occurred. In the following years Chikungunya moved to the Caribbean and South America. Recently also the USA experienced the spread of this virus and a limited outbreak based again on local spreading occurred in the French Department of Var, in August 2017.

“Oceans without Borders”: Dialectics of Transcolonial Labor Migration from the Indian Ocean World to the Atlantic Ocean World

2015 ◽  
Vol 87 ◽  
pp. 7-26 ◽  
Author(s):  
Yoshina Hurgobin ◽  
Subho Basu
Keyword(s):  
Indian Ocean ◽  
Atlantic Ocean ◽  
Labor Migration ◽  
Indentured Labor ◽  
Crucial Component ◽  
Global Demand ◽  
The Indian Ocean ◽  
In Trans ◽  
The Caribbean ◽  
Indian Ocean World

AbstractBy investigating the hitherto unstudied trans-colonial migration between Mauritius and the Caribbean in the nineteenth century, this article complicates liberal Eurocentric perceptions of global labor force formation under the auspices of colonial capital. Indeed, coercion, as depicted in liberal historiography, was a crucial component of indentured migration but indentured workers themselves sometimes availed of the opportunity of the global demand for their labor by engaging in trans-colonial migration. The dialectic of the formation of globalized indentured labor regime was such that while capital sought to confine workers to specific plantations, the very nature of the demand for labor enabled workers to defy the dictates of capital and further enabled them to move from one colony to another in search of better livelihoods and thus made them globally mobile. These migrations did not follow the so-called boundaries between the Indian Ocean and the Atlantic Ocean. Rather such migrations reflected workers’ search for jobs through trans-colonial networks within the framework of imperial domination.

Lower Cretaceous Deep-Water Benthic Foraminifera of the Indian Ocean

1998 ◽  
Vol 44 (2) ◽  
pp. 209
Author(s):  
W. A. Berggren ◽  
Anne E. L. Holbourn ◽  
Michael A. Kaminski
Keyword(s):  
Indian Ocean ◽  
Deep Water ◽  
Benthic Foraminifera ◽  
Lower Cretaceous ◽  
The Indian Ocean
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