scholarly journals Characteristics of Global Oceanic Rossby Wave and Mesoscale Eddies Propagation from Multiple Datasets Analysis

2016 ◽  
Author(s):  
Yunfan Zhang ◽  
Fenglin Tian ◽  
Ge Chen

Abstract. In this paper we present a research of propagation characteristics of global Rossby wave and mesoscale eddies, and we preliminarily discussing the relationship between them from multiple datasets analysis. By filtering the MSLA-H data and by means of optimized SSH method we have extracted signals of the Rossby wave, and estimated the propagation speed (zonal phase speed) of the Rossby wave and eddies. Validation for the identification of the Rossby wave also has been completed with the Argo temperature and salinity data. The prime focus covers: propagation speed comparison between the Rossby wave and the eddies, propagation characteristics in different regions. Overlaying the signals of the Rossby wave with the signatures of the eddies indicates that the Rossby wave and the eddies propagates together (westward only) in the mid-latitude, but differences appear with increasing of latitude, especially in some areas affected by ocean current, for instance, the West Wind Drift(WWD) and the North Atlantic Drift(NAD). Actually we have found that the currents led the eddies, and the Rossby wave might play an accelerative or moderative role in the eddies propagation, as a result of the velocities of the eddies and the currents were matched well, but comparison between the Rossby wave and the eddies revealed disparity. The findings are useful for understanding the relationship between the Rossby wave and mesoscale eddies.

2020 ◽  
Author(s):  
Kaveh Purkiani ◽  
André Paul ◽  
Annemiek Vink ◽  
Maren Walter ◽  
Michael Schulz ◽  
...  

Abstract. There has been a steady increase of interest in mining of deep-sea minerals in the Clarion-Clipperton Zone (CCZ) in the eastern Pacific Ocean during the last decade. This region is known to be one of the most eddy-rich regions in the world. Typically, mesoscale eddies are generated by intense wind bursts channelled through gaps in the Sierra Madre mountains in Central America. Here, we use a combination of satellite and in situ observations to evaluate the relationship between deep-sea current variability at the region of potential future mining and Eddy Kinetic Energy (EKE) in the vicinity of gap winds. A geometry-based eddy detection algorithm has been applied to altimetry sea surface height data for a period of 24 years from 1993 to 2016 in order to analyse the main characteristic parameters and the spatiotemporal variability of mesoscale eddies in the North-East Tropical Pacific Ocean (NETP). Significant differences between the characteristics of eddies with different polarity (cyclonic vs. anti-cyclonic) were found. For eddies with lifetimes longer than one day, cyclonic polarity is more numerous that anticyclonic rotation. However, anticyclonic eddies are larger in size, show stronger in vorticity, and survive longer in the ocean than cyclonic eddies (often 90 days or more). Besides the polarity of eddies, the location of eddy formation should be taken into consideration when investigating the impacted deep ocean region, as we found eddies originating from the Tehuantepec (TT) gap wind lasting longer in the ocean and travelling farther distances in a different direction compared to eddies produced by the Papagayo (PP) gap wind. Long-lived anticyclonic eddies generated by the TT gap wind are observed to travel distances up to 4500 km offshore, i.e. as far as west of 110 W. EKE anomalies observed in the surface of the central ocean at distances of ca. 2500 km from the coast correlate with the seasonal variability of EKE in the region of the TT gap winds with a time lag of 5–6 months. A significant seasonal variability of deep ocean current velocities at water depths of 4100 m was observed in multiple year time-series data likely reflecting the energy transfer of the surface EKE generated by the gap winds to the deep ocean. Furthermore, the influence of mesoscale eddies on deep ocean currents is examined by analyzing the deep ocean current measurements when an anticyclonic eddy crosses the study region. Our findings suggest that despite the significant modulation of dominant current directions driven by the bottom-reaching eddy, the current magnitude intensification was not strong enough to trigger local sediment resuspension in this region. A better insight of annual variability of ocean surface mesoscale activity in the CCZ and their effects on deep ocean current variability are of great help to mitigate the impact of the benthic ecosystem from future potential 1deep-sea mining activities. On an interannual scale, a significant relationship between cyclonic eddy characteristics and El-Niño Southern Oscillation (ENSO) was found, whereas no robust correlation was detected for anticyclonic eddies.


2007 ◽  
Vol 64 (10) ◽  
pp. 3424-3437 ◽  
Author(s):  
Gui-Ying Yang ◽  
Brian Hoskins ◽  
Julia Slingo

Abstract Following the description of the horizontal and vertical structures of convectively coupled equatorial waves presented in Part I, here their propagation characteristics are investigated. Linear lagged regressions are used to produce their composite evolution, and the Radon transform technique is used to calculate their phase speeds. It is shown that coherent wave structures with convective coupling generally exist for about 1–2 weeks. Typical zonal wavenumbers are 6–8, wavelengths are 42°–64° of longitude, and typical periods are 4–8 days. The eastward phase speed of convectively coupled Kelvin waves is between 10 and 17 m s−1. The westward phase speed of the coupled mixed Rossby–gravity wave is between 10 and 15 m s−1, and the westward phase speed of the coupled n = 1 Rossby wave is between 7 and 9 m s−1. It is found that convection can produce stronger vertical coupling of phase speeds, and Doppler shifting by the ambient flow can modify phase speeds. There is further evidence that some waves tend to act as forcing agents for convection whereas others tend to be forced by convection. Eastward propagation of some n = 0 and 1 modes in the upper troposphere is also examined.


Abstract It is well understood that isolated eddies are presumed to propagate westward intrinsically at the speed of the annual baroclinic Rossby wave. This classic description, however, is known to be frequently violated in both propagation speed and its direction in the real ocean. Here, we present a systematic analysis on the divergence of eddy propagation direction (i.e., global pattern of departure from due west) and dispersion of eddy propagation speed (i.e., zonal pattern of departure from Rossby wave phase speed). Our main findings include the following: 1) A global climatological phase map (the first of its kind to our knowledge) indicating localized direction of most likely eddy propagation has been derived from twenty-eight years (1993-2020) of satellite altimetry, leading to a leaf-like full-angle pattern in its overall divergence. 2) A meridional deflection map of eddy motion is created with prominent equatorward/poleward deflecting zones identified, revealing that it is more geographically correlated rather than polarity determined as previously thought (i.e., poleward for cyclonic eddies and equatorward for anticyclonic ones). 3) The eddy-Rossby wave relationship has a duality nature (waves riding by eddies) in five subtropical bands centered around 27°N and 26°S in the two hemispheres, outside which their relationship has a dispersive nature with dominant waves (eddies) propagating faster in the tropical (extratropical) oceans. Current, wind and topographic effects are major external forcings responsible for the observed divergence and dispersion of eddy propagations. These results are expected to make a significant contribution to eddy trajectory prediction using physically based and/or data-driven models.


2018 ◽  
Vol 69 (2) ◽  
pp. 199-236
Author(s):  
Martin Braxatoris ◽  
Michal Ondrejčík

Abstract The paper proposes a basis of theory with the aim of clarifying the casual nature of the relationship between the West Slavic and non-West Slavic Proto-Slavic base of the Slovak language. The paper links the absolute chronology of the Proto-Slavic language changes to historical and archaeological information about Slavs and Avars. The theory connects the ancient West Slavic core of the Proto-Slavic base of the Slovak language with Sclaveni, and non-West Slavic core with Antes, which are connected to the later population in the middle Danube region. It presumes emergence and further expansion of the Slavic koiné, originally based on the non-West Slavic dialects, with subsequent influence on language of the western Slavic tribes settled in the north edge of the Avar Khaganate. The paper also contains a periodization of particular language changes related to the situation in the Khaganate of that time.


Think India ◽  
2019 ◽  
Vol 22 (3) ◽  
pp. 186-192
Author(s):  
Dr. Oinam Ranjit Singh ◽  
Dr. Nushar Bargayary

The Bodo of the North Eastern region of India have their own kinship system to maintain social relationship since ancient periods. Kinship is the expression of social relationship. Kinship may be defined as connection or relationships between persons based on marriage or blood. In each and every society of the world, social relationship is considered to be the more important than the biological bond. The relationship is not socially recognized, it fall outside the realm of kinship. Since kinship is considered as universal, it plays a vital role in the socialization of individuals and the maintenance of social cohesion of the group. Thus, kinship is considered to be the study of the sum total of these relations. The kinship of the Bodo is bilateral. The kin related through the father is known as Bahagi in Bodo whereas the kin to the mother is called Kurma. The nature of social relationships, the kinship terms, kinship behaviours and prescriptive and proscriptive rules are the important themes of the present study.


2020 ◽  
Vol 3 (2) ◽  
pp. 226
Author(s):  
Arik Dwijayanto ◽  
Yusmicha Ulya Afif

<p><em>This article explores the concept of a religious state proposed by two Muslim leaders: Hasyim Asyari (1871-1947), an Indonesian Muslim leader and Muhammad Iqbal (1873-1938), an Indian Muslim leader. Both of them represented the early generation when the emerging revolution for the independence of Indonesia (1945) from the Dutch colonialism and India-Pakistan (1947) from the British Imperialism. In doing so, they argued that the religious state is compatible with the plural nation that has diverse cultures, faiths, and ethnicities. They also argued that Islam as religion should involve the establishment of a nation-state. But under certain circumstances, they changed their thinking. Hasyim changed his thought that Islam in Indonesia should not be dominated by a single religion and state ideology. Hasyim regarded religiosity in Indonesia as vital in nation-building within a multi-religious society. While Iqbal changed from Indian loyalist to Islamist loyalist after he studied and lived in the West. The desire of Iqbal to establish the own state for the Indian Muslims separated from Hindus was first promulgated in 1930 when he was a President of the Muslim League. Iqbal expressed the hope of seeing Punjab, the North West province, Sind and Balukhistan being one in a single state, having self-government outside the British empire. In particular, the two Muslim leaders used religious legitimacy to establish political identity. By using historical approach (intellectual history), the relationship between religion, state, and nationalism based on the thinking of the two Muslim leaders can be concluded that Hasyim Asyari more prioritizes Islam as the ethical value to build state ideology and nationalism otherwise Muhammad Iqbal tends to make Islam as the main principle in establishment of state ideology and nationalism.</em></p><em>Keywords: Hasyim Asyari, Muhammad Iqbal, religion, state, nationalism.</em>


2005 ◽  
Vol 156 (8) ◽  
pp. 288-296
Author(s):  
Vittorio Magnago Lampugnani

In the first half of the 19th century scientific philosophers in the United States, such as Emerson and Thoreau, began to pursue the relationship between man and nature. Painters from the Hudson River School discovered the rural spaces to the north of New York and began to celebrate the American landscape in their paintings. In many places at this time garden societies were founded, which generated widespread support for the creation of park enclosures While the first such were cemeteries with the character of parks, housing developments on the peripheries of towns were later set in generous park landscapes. However, the centres of the growing American cities also need green spaces and the so-called «park movement»reached a first high point with New York's Central Park. It was not only an experimental field for modern urban elements, but even today is a force of social cohesion.


2019 ◽  
pp. 42-44
Author(s):  
I.V. GUSAROV ◽  
V.A. OSTAPENKO ◽  
T.V. NOVIKOVА

Впервые в мире создана популяция зубров на территории 60 градусов северной широты. В новых климатических условиях разведения и сохранения зубров определены и проанализированы факторы существования вида на севере Европейской части РФ. Выявлены признаки, динамика численности, которые являются составной частью системы, предназначенной для управления биоразнообразием. Интродукция, являясь процессом введения в экосистему нехарактерных для нее видов, может усиливать изменения биоценозов как положительно, так и отрицательно. Насколько быстро и успешно проходит процесс адаптации заселенного вида, и усматривается его влияние на окружающую среду зависит дальнейшее существование зубров и в целом биоразнообразия. В статье обсуждаются вопросы взаимоотношения зубров с другими видами копытных и хозяйственной деятельностью человека, а также дальнейшим использованием зубров в сельскохозяйственном производстве. Пластичность зубров, выявление изменений и их анализ при вселении видов в новые условия обитания необходимы не только для определения развития или деградации биоценозов и в целом экосистемы, но и прогноза социально-экономических последствий интродукции как одного из методов сохранения редких и исчезающих видов фауны.For the first time in the world, a bison population has been created in an area of 60 degrees north latitude. In the new climatic conditions of breeding and preservation of bison, the factors of the species existence in the north of the European part of the Russian Federation are identified and analyzed. The signs, dynamics of abundance, which are an integral part of the system designed to manage biodiversity are identified, since the preservation of biological diversity on the planet is one of the main problems of our time. Introduction, being the process of introducing non-typical species into an ecosystem, can enhance changes in biocenoses, both positively and negatively. The question posing sounds especially when it comes to such a large hoofed animal as the European bison. How quickly and successfully the process of adaptation of the universe takes place and its environmental impact is seen depends on the continued existence of bison and biodiversity in general. The article discusses the relationship of bison with other types of ungulates and human activities, as well as the further use of bison in agricultural production. How these issues will be resolved positively depends on the future of these animals. Thus, the plasticity of bison, the identification of changes and their analysis, with the introduction of species into new habitat conditions is necessary not only to determine the development or degradation of biocenoses and the ecosystem as a whole, but also to predict the socio-economic consequences due to the introduction as one of the methods of preserving rare and endangered species of fauna.


Author(s):  
Debi Angelina Br. Barus

This study aims to determine the relationship of work values with the Batak Toba ethnic. This research was conducted at the Mobile Brigade Unit of the North Sumatra Regional Police. The subjects in this study were 45 people. This study uses a quantitative description approach. The results of the study are to find that hamoraon, hagabeon and hasangapon (3H) are in line with the principle of the work value of Brimob members. 3H is the peak achievement of individual Toba Batak ethnic work value in the mobile brigade unit of the North Sumatra regional police. Keyword: Work value, Batak Toba Etnic   Penelitian ini bertujuan untuk mengetahui hubungan nilai kerja dengan etnis Batak Toba. Penelitian ini dilakukan di Satuan Brigade Mobile Kepolisian Daerah Sumatera Utara. Subjek dalam penelitian ini adalah 45 orang. Penelitian ini menggunakan pendekatan kuantitatif deskripsi. Hasil penelitian adalah menemukan bahwa hamoraon, hagabeon dan hasangapon (3H) sejalan dengan prinsip nilai kerja pada satuan anggota Brimob. 3H merupakan puncak pencapaian dari nilai kerja individu yang beretnis Batak Toba di satuan brigade mobile kepolisian daerah Sumatera Utara. Kata Kunci: Nilai kerja, Etnis Batak Toba


2020 ◽  
Vol 2 (8) ◽  
pp. 101-110
Author(s):  
N. N. ILYSHEVA ◽  
◽  
E. V. KARANINA ◽  
G. P. LEDKOV ◽  
E. V. BALDESKU ◽  
...  

The article deals with the problem of achieving sustainable development. The purpose of this study is to reveal the relationship between the components of sustainable development, taking into account the involvement of indigenous peoples in nature conservation. Climate change makes achieving sustainable development more difficult. Indigenous peoples are the first to feel the effects of climate change and play an important role in the environmental monitoring of their places of residence. The natural environment is the basis of life for indigenous peoples, and biological resources are the main source of food security. In the future, the importance of bioresources will increase, which is why economic development cannot be considered independently. It is assumed that the components of resilience are interrelated and influence each other. To identify this relationship, a model for the correlation of sustainable development components was developed. The model is based on the methods of correlation analysis and allows to determine the tightness of the relationship between economic development and its ecological footprint in the face of climate change. The correlation model was tested on the statistical materials of state reports on the environmental situation in the Khanty-Mansiysk Autonomous Okrug – Yugra. The approbation revealed a strong positive relationship between two components of sustainable development of the region: economy and ecology.


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