scholarly journals Global mapping of 10-day differences of temperature and salinity in the intermediate layer observed with Argo floats

Author(s):  
Yoshimi Kawai ◽  
Shigeki Hosoda

AbstractThe authors examine small-scale spatiotemporal variability of the layer nearly 2000-m depth, which is the “bottom” of the present Argo observation system, using all of available Argo float data. The 10-day change, ΔT10, is defined as the difference of temperature between two successive observations with an interval of nearly 10 days for each individual float at an isobaric surface. |ΔT10| is large along the western boundary currents at 1000 dbar, and becomes less remarkable with depth. At 1950 dbar, mean |ΔT10| is noticeable in the northeastern Atlantic Ocean (NEAO), the Argentine basin, and the northwestern Indian Ocean. In the Southern Ocean, large |ΔT10| is localized in some areas located over the ridges or leeward of the plateau. Basically, ΔT10 at isobaric surfaces is accounted for by the heave component, but the spiciness component is dominant or comparable to the other in the NEAO and the Argentine basin. ΔT10 decreases with depth monotonically most of the world, suggesting that wind energy input is attenuated with depth. In some areas in the Southern Ocean, however, the vertical profile of |ΔT10| implies enhanced bottom-induced turbulence. |ΔT10| peaks at 1300 dbar in the NEAO, corresponding to the spread of the Mediterranean Outflow Water. |ΔT10| is smaller in the Pacific Ocean compared with the other oceans, but is enhanced along the equator, the Kuroshio and its Extension, the Kuril, Aleutian, Hawaii, and Mariana Islands, and the Emperor Seamount Chain.

2019 ◽  
Vol 49 (8) ◽  
pp. 2147-2164 ◽  
Author(s):  
Yang Yang ◽  
X. San Liang

AbstractUsing a new analysis tool, namely, multiscale window transform (MWT), and the MWT-based theory of canonical transfer, this study investigates the spatiotemporal variations of the nonlinear interactions among the mean flows, interannual variabilities, quasi-annual fluctuations, and eddies in the global ocean. It is found that the canonical kinetic energy (KE) transfers are highly inhomogeneous in space, maximized in the western boundary current (WBC), Southern Ocean, and equatorial regions. In contrast to the equatorial and WBC regions where the temporal KE cascades are mainly forward, the Southern Ocean is the very place where coherent large-scale patterns of inverse KE cascade take place. The canonical transfers are also found to be highly variable in time. Specifically, in the Kuroshio Extension, the transfer from the mean flow to the interannual variability is in pace with the external winds from the eastern North Pacific; in the subtropical gyre, the mean flow-to-eddy transfer is responsible for the variability of the eddy kinetic energies (EKE) at both interannual and seasonal scales; in the tropics, the downscale transfers to the eddies from the other three scales all contribute to the interannual modulation of the EKE, and these transfers tend to decrease (increase) during El Niño (La Niña) events. In the Southern Ocean, the high-frequency eddies are found to feed KE to the low-frequency variability through temporal inverse cascade processes, which have been strengthened due to the enhanced eddy activities in the recent decade. Also discussed here is the relation between the seasonal EKE variability and the eddy–quasi-annual fluctuation interaction.


2017 ◽  
Vol 11 (2) ◽  
pp. 707-722 ◽  
Author(s):  
Shuang-Ye Wu ◽  
Shugui Hou

Abstract. Productivity in the Southern Ocean (SO) is iron-limited, and supply of iron dissolved from aeolian dust is believed to be the main source from outside the marine environment. However, recent studies show that icebergs could provide a comparable amount of bioavailable iron to the SO as aeolian dust. In addition, small-scale areal studies suggest increased concentrations of chlorophyll, krill, and seabirds surrounding icebergs. Based on previous research, this study aims to examine whether iceberg occurrence has a significant impact on marine productivity at the scale of the SO, using remote sensing data of iceberg occurrences and ocean net primary productivity (NPP) covering the period 2002–2014. The impacts of both large and small icebergs are examined in four major ecological zones of the SO: the continental shelf zone (CSZ), the seasonal ice zone (SIZ), the permanent open ocean zone (POOZ), and the polar front zone (PFZ). We found that the presence of icebergs is associated with elevated levels of NPP, but the differences vary in different zones. Grid cells with small icebergs on average have higher NPP than other cells in most iron-deficient zones: 21 % higher for the SIZ, 16 % for the POOZ, and 12 % for the PFZ. The difference is relatively small in the CSZ where iron is supplied from meltwater and sediment input from the continent. In addition, NPP of grid cells adjacent to large icebergs on average is 10 % higher than that of control cells in the vicinity. The difference is larger at higher latitudes, where most large icebergs are concentrated. From 1992 to 2014, there is a significant increasing trend for both small and large icebergs. The increase was most rapid in the early 2000s and has leveled off since then. As the climate continues to warm, the Antarctic Ice Sheet is expected to experience increased mass loss as a whole, which could lead to more icebergs in the region. Based on our study, this could result in a higher level of NPP in the SO as a whole, providing a possible negative feedback for global warming in near future.


Author(s):  
Akihiro Yoshimura ◽  
Koyo Suemasu ◽  
Marcello M. Veiga

Abstract Artisanal and small-scale gold mining (ASGM) utilizes mercury (Hg) for the extraction of gold (Au) and is responsible for the largest anthropogenic source of emissions and releases of Hg to the environment. Previous estimates of Hg use in ASGM have varied widely. In this effort, Hg losses in ASGM were derived from the difference between estimates of total Au production and the production reported by conventional gold mining. On the basis of this result, the average ratio of Hg lost to Au produced in ASGM was estimated to be 1.96 in Africa, 4.63 in Latin America, and 1.23 in Asia. The difference among regions can be attributed to the amalgamation procedure used by the miners, in which whole-ore amalgamation is predominant in Latin America and Asia. The obtained estimated ratio of Hglost:Auproduced suggested the possibility to detect either Au or Hg smuggling from one country to another. On the other hand, the importance of considering cyanidation in ASGM was also suggested. Graphical Abstract


1973 ◽  
Vol 29 (02) ◽  
pp. 490-498 ◽  
Author(s):  
Hiroh Yamazaki ◽  
Itsuro Kobayashi ◽  
Tadahiro Sano ◽  
Takio Shimamoto

SummaryThe authors previously reported a transient decrease in adhesive platelet count and an enhancement of blood coagulability after administration of a small amount of adrenaline (0.1-1 µg per Kg, i. v.) in man and rabbit. In such circumstances, the sensitivity of platelets to aggregation induced by ADP was studied by an optical density method. Five minutes after i. v. injection of 1 µg per Kg of adrenaline in 10 rabbits, intensity of platelet aggregation increased to 115.1 ± 4.9% (mean ± S. E.) by 10∼5 molar, 121.8 ± 7.8% by 3 × 10-6 molar and 129.4 ± 12.8% of the value before the injection by 10”6 molar ADP. The difference was statistically significant (P<0.01-0.05). The above change was not observed in each group of rabbits injected with saline, 1 µg per Kg of 1-noradrenaline or 0.1 and 10 µg per Kg of adrenaline. Also, it was prevented by oral administration of 10 mg per Kg of phenoxybenzamine or propranolol or aspirin or pyridinolcarbamate 3 hours before the challenge. On the other hand, the enhancement of ADP-induced platelet aggregation was not observed in vitro, when 10-5 or 3 × 10-6 molar and 129.4 ± 12.8% of the value before 10∼6 molar ADP was added to citrated platelet rich plasma (CPRP) of rabbit after incubation at 37°C for 30 second with 0.01, 0.1, 1, 10 or 100 µg per ml of adrenaline or noradrenaline. These results suggest an important interaction between endothelial surface and platelets in connection with the enhancement of ADP-induced platelet aggregation by adrenaline in vivo.


Author(s):  
Philip Isett

This chapter presents the equations and calculations for energy approximation. It establishes the estimates (261) and (262) of the Main Lemma (10.1) for continuous solutions; these estimates state that we are able to accurately prescribe the energy that the correction adds to the solution, as well as bound the difference between the time derivatives of these two quantities. The chapter also introduces the proposition for prescribing energy, followed by the relevant computations. Each integral contributing to the other term can be estimated. Another proposition for estimating control over the rate of energy variation is given. Finally, the coarse scale material derivative is considered.


Metahumaniora ◽  
2017 ◽  
Vol 7 (3) ◽  
pp. 378
Author(s):  
Vincentia Tri Handayani

AbstrakFolklor yang menghasilkan tradisi lisan merupakan perwujudan budaya yang lahirdari pengalaman kelompok masyarakat. Salah satu bentuk tradisi lisan adalah ungkapan yangmengandung unsur budaya lokal dalam konstruksinya yang tidak dimiliki budaya lainnya.Ungkapan idiomatis memberikan warna pada bahasa melalui penggambaran mental. Dalambahasa Perancis, ungkapan dapat berupa locution dan expression. Perbedaan motif acuansuatu ungkapan dapat terlihat dari pengaruh budaya masyarakat pengguna bahasa. Sebuahleksem tidak selalu didefinisikan melalui unsur minimal, tidak juga melalui kata-kata,baik kata dasar atau kata kompleks, namun dapat melalui kata-kata beku yang maknanyatetap. Hubungan analogis dari makna tambahan yang ada pada suatu leksem muncul dariidentifikasi semem yang sama. Semem tersebut mengarah pada term yang diasosiasikan danyang diperkaya melalui konteks (dalam ungkapan berhubungan dengan konteks budaya).Kata kunci: folklor, ungkapan, struktur, makna idiomatis, kebudayaanAbstractFolklore which produces the oral tradition is a cultural manifestation born out theexperience of community groups. One form of the oral tradition is a phrase that containsthe elements of local culture in its construction that is not owned the other culture. Theidiomatic phrase gives the color to the language through the mental representation. InFrench, the expression can consist of locution and expression. The difference motivesreference of an expression can be seen from the influence of the cultural community thelanguage users. A lexeme is not always defined through a minimal element, nor throughwords, either basic or complex words, but can be through the frost words whose meaningsare fixed. The analogical connection of the additional meanings is on a lexeme arises fromthe identification of the same meaning. The meaning ‘semem’ leads to the associated termsand which are enriched through the context (in idiom related to the cultural context).Keywords : folklore, idioms, structure, idiom meaning, cultureI PENDAHULUAN


2013 ◽  
Vol 62 (1) ◽  
pp. 23-31 ◽  
Author(s):  
Maria Mrówczyńska

Abstract The paper attempts to determine an optimum structure of a directional measurement and control network intended for investigating horizontal displacements. For this purpose it uses the notion of entropy as a logarithmical measure of probability of the state of a particular observation system. An optimum number of observations results from the difference of the entropy of the vector of parameters ΔHX̂ (x)corresponding to one extra observation. An increment of entropy interpreted as an increment of the amount of information about the state of the system determines the adoption or rejection of another extra observation to be carried out.


Author(s):  
Michel Meyer

Rhetoric has always been torn between the rhetoric of figures and the rhetoric of conflicts or arguments, as if rhetoric were exclusively one or the other. This is a false dilemma. Both types of rhetoric hinge on the same structure. A common formula is provided in Chapter 3 which unifies rhetoric stricto sensu and rhetoric as argumentation as two distinct but related strategies adopted according to the level of problematicity of the questions at stake, thereby giving unity to the field called “Rhetoric.” Highly problematic questions require arguments to justify their answers; non-divisive ones can be treated rhetorically through their answers as if they were self-evident. Another classic problem is how to understand the difference between logic and rhetoric. The difference between the two is due to the presence of questions explicitly answered in the premises in logic and only suggested (or remaining indeterminate) in rhetoric.


Author(s):  
D. T. Gauld ◽  
J. E. G. Raymont

The respiratory rates of three species of planktonic copepods, Acartia clausi, Centropages hamatus and Temora longicornis, were measured at four different temperatures.The relationship between respiratory rate and temperature was found to be similar to that previously found for Calanus, although the slope of the curves differed in the different species.The observations on Centropages at 13 and 170 C. can be divided into two groups and it is suggested that the differences are due to the use of copepods from two different generations.The relationship between the respiratory rates and lengths of Acartia and Centropages agreed very well with that previously found for other species. That for Temora was rather different: the difference is probably due to the distinct difference in the shape of the body of Temora from those of the other species.The application of these measurements to estimates of the food requirements of the copepods is discussed.


2020 ◽  
Vol 3 (1) ◽  
pp. 61
Author(s):  
Kazuhiro Aruga

In this study, two operational methodologies to extract thinned woods were investigated in the Nasunogahara area, Tochigi Prefecture, Japan. Methodology one included manual extraction and light truck transportation. Methodology two included mini-forwarder forwarding and four-ton truck transportation. Furthermore, a newly introduced chipper was investigated. As a result, costs of manual extractions within 10 m and 20 m were JPY942/m3 and JPY1040/m3, respectively. On the other hand, the forwarding cost of the mini-forwarder was JPY499/m3, which was significantly lower than the cost of manual extractions. Transportation costs with light trucks and four-ton trucks were JPY7224/m3 and JPY1298/m3, respectively, with 28 km transportation distances. Chipping operation costs were JPY1036/m3 and JPY1160/m3 with three and two persons, respectively. Finally, the total costs of methodologies one and two from extraction within 20 m to chipping were estimated as JPY9300/m3 and JPY2833/m3, respectively, with 28 km transportation distances and three-person chipping operations (EUR1 = JPY126, as of 12 August 2020).


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