Drifter-derived estimates of lateral eddy diffusivity in the World Ocean with emphasis on the Indian Ocean and problems of parameterisation

2014 ◽  
Vol 83 ◽  
pp. 1-11 ◽  
Author(s):  
Victor Zhurbas ◽  
Dmitry Lyzhkov ◽  
Natalia Kuzmina
Keyword(s):  
Indian Ocean ◽  
World Ocean ◽  
Eddy Diffusivity ◽  
The World ◽  
The Indian Ocean

scholarly journals Phylogenetic phytogeography of the family Cymodoceaceae

2020 ◽  
Vol 19 (2) ◽  
pp. 094-097
Author(s):  
А. А. Iurmanov ◽  
M. S. Romanov ◽  
A. V. Bobrov
Keyword(s):  
Indian Ocean ◽  
World Ocean ◽  
Southern Coast ◽  
Tropical Waters ◽  
The Family ◽  
The World ◽  
The Indian Ocean

The oldest representatives of Cymodoceaceae supposedly arose in the tropical waters of East Gondwana inCretaceous and later settled along the World Ocean by various tracks, the most important of which passed along the southern coast of Eurasian continental masses and reached the waters of modern Atlantic. More advanced genera Cymodocea,Syringodium originated in these areas and moved “back” to the waters of the Indian Ocean and the southwestern Pacific.

scholarly journals Distribution of methane fluxes on the water–atmosphere interface in different regions of the World Ocean

2021 ◽  
Vol 5 (3) ◽  
pp. 240-254
Author(s):  
G.I. Mishukova ◽  
◽  
A.V. Yatsuk ◽  
R.B. Shakirov ◽  
◽  
...  
Keyword(s):  
Indian Ocean ◽  
Subsurface Layer ◽  
World Ocean ◽  
Water Layer ◽  
Water Area ◽  
The World ◽  
Methane Fluxes ◽  
The Indian Ocean ◽  
Indian And Atlantic Oceans ◽  
Methane Concentrations

For the first time, methane fluxes at the water-atmosphere interface were calculated for the water area of Pacific, Indian, and Atlantic oceans (for the area about 30,000 miles) on the basis of the expeditionary measurements of methane concentrations in the surface layer of water and subsurface layer of the atmosphere along the entire course of the vessel. Methane fluxes at the water-atmosphere interface were calculated for the water areas of the Pacific, Indian and Atlantic oceans. In the result of the studies carried out in various regions of the World Ocean, an uneven spatial distribution of methane fluxes from strong absorption to emission of anomalous intensity was observed. The article presents the results of a detailed study for the deepwater area of the Indian Ocean open waters in the northern part of the Ninetyeast Ridge. Both supersaturation and undersaturation of seawater respectively to its concentrations in the atmosphere have been revealed on the basis of the direct measurements of methane concentrations in the ocean surface water layer. The distribution of dissolved methane in the water column of the Indian Ocean has been considered.

scholarly journals Can We Infer Diapycnal Mixing Rates from the World Ocean Temperature–Salinity Distribution?

2016 ◽  
Vol 46 (12) ◽  
pp. 3751-3775 ◽  
Author(s):  
Olivier Arzel ◽  
Alain Colin de Verdière
Keyword(s):  
General Circulation ◽  
Large Scale ◽  
Water Mass ◽  
World Ocean ◽  
Eddy Diffusivity ◽  
Regional Variability ◽  
Diapycnal Mixing ◽  
Inverse Models ◽  
The World ◽  
The Difference

AbstractThe turbulent diapycnal mixing in the ocean is currently obtained from microstructure and finestructure measurements, dye experiments, and inverse models. This study presents a new method that infers the diapycnal mixing from low-resolution numerical calculations of the World Ocean whose temperatures and salinities are restored to the climatology. At the difference of robust general circulation ocean models, diapycnal diffusion is not prescribed but inferred. At steady state the buoyancy equation shows an equilibrium between the large-scale diapycnal advection and the restoring terms that take the place of the divergence of eddy buoyancy fluxes. The geography of the diapycnal flow reveals a strong regional variability of water mass transformations. Positive values of the diapycnal flow indicate an erosion of a deep-water mass and negative values indicate a creation. When the diapycnal flow is upward, a diffusion law can be fitted in the vertical and the diapycnal eddy diffusivity is obtained throughout the water column. The basin averages of diapycnal diffusivities are small in the first 1500 m [O(10−5) m2 s−1] and increase downward with bottom values of about 2.5 × 10−4 m2 s−1 in all ocean basins, with the exception of the Southern Ocean (50°–30°S), where they reach 12 × 10−4 m2 s−1. This study confirms the small diffusivity in the thermocline and the robustness of the higher canonical Munk’s value in the abyssal ocean. It indicates that the upward dianeutral transport in the Atlantic mostly takes place in the abyss and the upper ocean, supporting the quasi-adiabatic character of the middepth overturning.

scholarly journals Africa and the wider world: creole communities in the Atlantic and Indian Oceans

Tempo ◽  
2017 ◽  
Vol 23 (3) ◽  
pp. 465-481
Author(s):  
Malyn Newitt
Keyword(s):  
Technology Transfer ◽  
Indian Ocean ◽  
World Economy ◽  
Sub Saharan Africa ◽  
Eastern Africa ◽  
Cultural Appropriation ◽  
The World ◽  
African Slaves ◽  
The Indian Ocean ◽  
Sub Saharan

Abstract: Portuguese creoles were instrumental in bringing sub-Saharan Africa into the intercontinental systems of the Atlantic and Indian Ocean. In the Atlantic Islands a distinctive creole culture emerged, made up of Christian emigrants from Portugal, Jewish exiles and African slaves. These creole polities offered a base for coastal traders and became politically influential in Africa - in Angola creating their own mainland state. Connecting the African interior with the world economy was largely on African terms and the lack of technology transfer meant that the economic gap between Africa and the rest of the world inexorably widened. African slaves in Latin America adapted to a society already creolised, often through adroit forms of cultural appropriation and synthesis. In eastern Africa Portuguese worked within existing creolised Islamic networks but the passage of their Indiamen through the Atlantic created close links between the Indian Ocean and Atlantic commercial systems.

Sovereignty in a Minor Key

2021 ◽  
Vol 33 (1) ◽  
pp. 41-61
Author(s):  
Thomas Blom Hansen
Keyword(s):  
Twentieth Century ◽  
Eighteenth Century ◽  
Indian Ocean ◽  
Western Europe ◽  
Nation State ◽  
The World ◽  
The Indian Ocean ◽  
Theories Of Sovereignty ◽  
A Minor ◽  
State Form

Abstract Theories of sovereignty in the twentieth century are generally based on a teleological “out-of-Europe” narrative where the modern, centralized nation-state form gradually spread across the world to be the foundation of the international order. In this article, the author reflects on how the conceptualization of sovereignty may change if one begins a global account of modern sovereignty not from the heart of Western Europe but from the complex arrangements of “distributed sovereignty” that emerged in the Indian Ocean and other colonized territories from the eighteenth century onward. These arrangements were organized as multiple layers of dependency and provisional domination, captured well by Eric Beverley's term minor sovereignty. Thinking through sovereignty in a minor key allows us to see sovereignty less as a foundation of states and societies and more as a performative category, emerging in a dialectic between promises of order, prosperity, and law, and the realities of violent domination and occupation.

Uneasy Litter Mates: Population and Progress

1993 ◽  
Author(s):  
Garrett Hardin
Keyword(s):  
Indian Ocean ◽  
Possible Worlds ◽  
New World ◽  
Tenth Century ◽  
Manifest Destiny ◽  
Fifth Century ◽  
Human Species ◽  
The World ◽  
The Indian Ocean ◽  
Southern Iraq

In the fifth century B.C., Herodotus reported that there had been a time when a person could walk across North Africa from the Atlantic to the Indian Ocean and be always in the shade of trees. No more: the land was well on the way to becoming the desert we know today. Herodotus generalized: "Man stalks across the landscape, and deserts follow in his footsteps." In the tenth century A.D., a Samanid prince identified four earthly paradises: the regions of Samarkand, southern Persia, southern Iraq, and Damascus. No one who has visited any of these sites now would dream of calling it a paradise. They have been cursed with wars, but warfare is only a secondary cause of their degradation. Throughout history human exploitation of the earth has produced this progression: colonize—destroy—move on. When the Pollyannas write history they focus only on the first of these three actions, the desirable effects of which were most evident during the rapid colonization of the New World. In 1845 a now obscure American journalist coined a deathless phrase when he spoke of "the fulfillment of our manifest destiny to overspread the continent allotted by Providence." "Manifest destiny" is one of those catchphrases we love. We would not welcome the words of a journalist who identified colonization as but a prelude to destruction and abandonment. The restless "moving on" of the human species has depended on always having fresh land to move to. Optimists are not easily frightened by the results, of course: as late as 1980 one Pollyanna brightly explained how all turned out for the best in this best of all possible worlds: "Each year deserts the world over engulf an area the size of Massachusetts. A great deal of land lost is agricultural. . . . Fortunately, however, land is always being replaced or coming under cultivation to make up for land lost." An ecologist—ever guided by the question "And then what?"—would insist on a clarification of the above quotation: Does "always" mean "forever"? If so, it implies that there are no limits to earthly space. It is not surprising that ecologists are not the most popular of people in a growth-oriented economy.

Multiobjective Algorithm-Based Pareto Optimization for Modelling Trajectory Movement of MH370 Debris

2020 ◽  
pp. 281-309
Keyword(s):  
Indian Ocean ◽  
Ocean Circulation ◽  
Optimal Algorithm ◽  
World Ocean ◽  
Pareto Optimization ◽  
Altimeter Data ◽  
Dynamic Movement ◽  
The Indian Ocean ◽  
Global World ◽  
Current Circulation

It is well-known that the altimeter satellite data can model the global world ocean circulation. In this view, the ocean dynamic circulation altimeter data is required to understand the drift movement of MH370 across the Indian ocean. The integration between the Volterra-Lax-Wendroff algorithm and Pareto optimal algorithm is used to investigate the dynamic movement of MH370 debris over annual current circulation across the Indian Ocean. This chapter shows that the maximum value of the hit-rate (HR) is 160%, which is occurring with an extreme rapidity of eddy current of 0.65 m/s. In conclusion, it is a great impossibility for the existence of the debris along Mozambique, Reunion Island, Madagascar coastal waters, and Mossel Bay, South Africa, as proven by the Pareto optimization.

The Portuguese and the Indian Ocean : a review

Antiquity ◽  
1948 ◽  
Vol 22 (85) ◽  
pp. 4-7
Author(s):  
Elaine Sanceau
Keyword(s):  
Indian Ocean ◽  
16Th Century ◽  
The World ◽  
History Of ◽  
The Indian Ocean ◽  
The Subject ◽  
Century Literature

It was from the Portuguese that Europe first learned something about India. Their 16th century literature abounds in information on the subject. Duarte Barboza, Tomé Pires, Castanheda, João de Barros, Gaspar Correa even, though he says that he will only write about the exploits of his countrymen, have each one given to the world many interesting facts regarding the ethnology, the customs and beliefs, and some account of the history of that baffling sub-continent which Portugal, of European nations, was the first to observe at close quarters.

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