The east Greenland current (EGC) and the smaller east Greenland coastal current (EGCC) provide the major conduit for cold fresh polar water to enter the lower latitudes of the North Atlantic. They ...flow equatorward through the western Irminger Basin and around Cape Farewell into the Labrador Sea. The surface circulation and transport of the Cape Farewell boundary current region in summer 2005 is described. The EGCC merges with Arctic waters of the EGC to the south of Cape Farewell, forming the west Greenland current. The EGC transport decreases from 15.5 Sv south of Cape Farewell to 11.7 Sv in the eastern Labrador Sea (where the water becomes known as Irminger Sea Water). The decrease in EGC transport is balanced by the retroflection of a substantial proportion of the boundary current (5.1 Sv) into the central Irminger Basin; a new pathway for fresh water into the interior of the subpolar gyre.
The East Madagascar Current (EMC) is one of the western boundary currents of the South Indian Ocean. As such, it plays an important role in the climate system by transporting water and heat toward ...the pole and recirculating to the large‐scale Indian Ocean through retroflection modes of its southern extension. Five cruise data sets and remote sensing data from different sensors are used to identify three states of the southern extension of the EMC: early retroflection, canonical retroflection, and no retroflection. Retroflections occur 47% of the time. EMC strength regulates the retroflection state, although impinged mesoscale eddies also contribute to retroflection formation. Early retroflection is linked with EMC volume transport. Anticyclonic eddies drifting from the central Indian Ocean to the coast favor early retroflection formation, anticyclonic eddies near the southern tip of Madagascar promote the generation of canonical retroflection, and no retroflection appears to be associated with a lower eddy kinetic energy (EKE). Knowledge of the EMC retroflection state could help predict (a) coastal upwelling south of Madagascar, (b) the southeastern Madagascar phytoplankton bloom, and (c) the formation of the South Indian Ocean Counter Current (SICC).
Plain Language Summary
Using in situ and satellite observations, we show that the East Madagascar Current (EMC), a strong current flowing along the East Coast of Madagascar, often detaches from the coast before the southern tip of the island and goes directly into the Indian Ocean, the so‐called EMC retroflection. The EMC retroflection is characterized by three well‐defined forms: early retroflection, canonical retroflection, and no retroflection. The EMC Early Retroflection is an unusual abrupt return current straight to the Indian Ocean without reaching the detachment point, while the EMC Canonical Retroflection returns the mass flow in the vicinity of the southern tip of the island. No retroflection is characterized by the straight propagation of the flow toward the Agulhas Current. These three forms of retroflection are due to the strength of the EMC and the contribution of mesoscale eddies arriving from the Indian Ocean. Retroflections have implications for coastal upwelling strength, Southeast Madagascar phytoplankton bloom occurrences, and South Indian Ocean Counter Current (SICC) formation.
Key Points
The East Madagascar Current (EMC) retroflection is assessed. Evidence of EMC early retroflection is demonstrated for the first time
Retroflection regimes are associated with EMC strength and mesoscale variability
Knowledge of the EMC retroflection state helps understand regional ecosystem variability
A 12.7-year series of weekly absolute sea surface height (SSH) data in the region south of Africa is used for a statistical characterization of the location of the Agulhas Current retroflection and ...its variations at periods up to 2 years. The highest probability of presence of the retroflection point is at ∼39.5°S/18–20°E. The longitudinal probability density is negatively skewed. A sharp eastward decrease at 22°E is related to detachments of the Agulhas Current from the continental slope at this longitude. The asymmetry in the central part of the distribution might reflect a westward increase of the zonal velocity of the retroflection point during its east–west pulsations. The western tail of the distribution reveals larger residence times of the retroflection at 14°E–15°E, possibly related to a slowing down of its westward motion by seamounts. While the averaged zonal velocity component of the retroflection point increases westward, its modulus exhibits an opposite trend, the result of southward velocity components more intense in the northeastern Agulhas Basin than farther west. These meridional motions likely reflect influences by cyclones adjacent to the Agulhas Current south of the Agulhas Bank, and farther west in the Cape Basin. In the latter area, variations of the meridional motions result in different positions of the westernmost retroflection patterns relative to the neighbouring seamounts, likely influencing the future behaviour of Agulhas rings shed at these locations. Agulhas ring formation at an average yearly rate of 5.8, similar to previous findings, was observed to occur west of ∼19°E, in the western half of the retroflection probability domain. A well-defined seasonal signal of the retroflection longitude was found throughout the first 5 years of the time series, characterized by amplitudes of 1–1.3° of longitude, and western (eastern) extremes during austral summer (winter). This annual cycle was strongly phase shifted during and after the upstream retroflection event of 2000–2001.
Historical hydrographic data, spanning the period 1896–2006, are used to examine the annual mean and seasonal variations in the distribution of freshwater along and across the shelf/slope boundary ...along the Labrador and Newfoundland Shelves and the Grand Banks of Newfoundland. Particular attention is paid to the export of freshwater along the eastern Grand Banks, between Flemish Cap and the Tail of the Grand Banks, as this has long been identified as a preferential region for the loss of mass and freshwater from the boundary. The data are combined into isopycnally averaged long-term annual and monthly mean gridded property fields and the evolving distribution of fresh arctic-origin water is analyzed in fields of salinity anomaly, expressed as departures from the “central water” temperature–salinity relation of the Gulf Stream. The climatology confirms that cold/fresh northern-source waters are advected offshore within the retroflecting Labrador Current along the full length of the boundary between Flemish Cap and the Tail of the Grand Banks. In fact, it is estimated that most of the equatorward baroclinic transport at the boundary must retroflect back toward the north in order to explain the annual mean distribution of salinity in the climatology. While the retroflection of the Labrador Current appears seasonally robust, the freshwater distribution within the retroflection region varies in response to (1) the freshness of the water available for export which is set by the arrival and rapid flushing of the seasonal freshwater pulse at the boundary, (2) seasonal buoyancy forcing at the surface which alters the vertical stratification across the retroflection region, restricting certain isopycnal export pathways, and (3) the density structure along the eastern Grand Banks, which defines the progressive retroflection of the Labrador Current.
Loanwords often go under the adaptation process with native words. In loanwords adaptation, phonology has a vital role. The loanword phonology highlights more features in a particular language. The ...phonological pattern of loanword phonology is novel. It is the reflection of native phonology. The English loanwords are adapted in the Lasi. This paper addresses the questions: Which sounds are substituted in Lasi? and How substitutions with English loanwords occur in Lasi? The data are collected through observation and interviews. Optimality Theory is used for data analysis and presentation. It is the most used framework in the current era. Optimality Theory is used by Ito and Mester (1995, 1999), Davidson and Noyer (1996) Broselow (2004), and other constraint-based approaches by Paradis and LaCharité (1997), LaCharité and Paradis (2005) as well as Crawford (2007). Towards the end, it has been seen that an English loanword and its Lasi counterpart have a different structure, they are adopted and used by Lasi speakers in different ways, in their own style. Lasi natives prefer one feature-changing rule for ease of pronunciation. In English, loanwords adaptation terminal devoicing, continuant feature, retroflexion, and palatalization are common. Lasi natives prefer unmarked constraints in adaptation. These words are pronounced according to Lasi phonological pattern. It can be claimed on the base of the inputs and outputs that Lasi adapts English loanwords according to it is own pattern. The substitution processes take place while changing one feature. Substitutions have been occurred from marked to unmarked. The preference for a distinct features is given to the unmarked features. So, the process of lenition occurs in Lasi English loanwords. It is common that languages always prefer unmarked as compared to markedness. So, the same rule has been followed by Lasi.
The Agulhas Current with its retroflection and attendant eddy-shedding is the cause of some of the greatest mesoscale variability in the ocean. This paper considers the area to the south and east of ...Madagascar, which provides some of the source waters of the Agulhas Current, and examines the propagating sea surface height signals in altimetry and output from a numerical model, OCCAM. Both show bands of variability along the axis of the East Madagascar Current (EMC) and along a zonal band near 25°S. Sequences of images plus associated temperature data suggest that a number of westward-propagating eddies are present in this zonal band. The paper then focuses on the region to the south of the island, where ocean colour and infra-red imagery are evocative of an East Madagascar Retroflection. The synthesis of data analysed in this paper, however, shows that remotely observed features in this area can be explained by anticyclonic eddies moving westward through the region, and this explanation is consistent with numerical model output and the trajectories of drifting buoys.
The importance of the role played by the tropics in driving and propagating climate change between hemispheres has long been the focus of attention in a bid to evaluate ocean–atmosphere interactions ...on glacial–interglacial timescales. The Amazon Fan and Ceara Rise in the western equatorial Atlantic Ocean lie directly in the flowpath of the North Brazil Current (NBC) which, as a conduit for the cross-equatorial transport of heat and salinity, is a key component for the heat budget of the North Atlantic. Mg/Ca palaeothermometry and stable oxygen isotope analysis of planktonic foraminifera sampled from 15 sites across the Amazon Fan and Ceara Rise reveal variations in oceanic surface currents and of the dispersal of freshwater from the River Amazon over five timeslices (modern; early Holocene; Younger Dryas; Late Glacial and Marine Isotope Stage 3). Sea surface temperature reconstructions reveal progressive climatic amelioration over the last ~
30
ka, indicating a temperature increase of ~
3.2
±
1.1
°C since the Late Glacial. In conjunction with this warming, values of Δδ
18O, a proxy for water column stratification indicates increased vertical mixing of the glacial ocean. The spatial distribution of values of δ
18w (the isotopic composition of ambient seawater) is used to infer surface current variations and demonstrates an oceanward shift in the river outflow plume in cold climates representing a prolongation or possibly permanent continuation in the duration of the seasonal retroflection of the NBC causing the curtailment of cross-equatorial transport. A prolongation of this retroflection could have resulted from a mean southward migration of the southern boundary of the ITCZ.
► Spatial and temporal differences in tropical Atlantic Ocean surface water currents. ► Prolonged retroflection of North Brazil Current curtails northward heat transport. ► Glacial–interglacial temperature difference of 3.2
°C.
The exchange of heat and salt between the South Indian Ocean and South Atlantic Ocean, at the southern terminus of the Agulhas current, forms a crucial link in the global ocean circulation. It has ...been surmised that upstream retroflections in this current could produce temporary interruptions to the exchange, but that their impact would depend on the vertical extent of such retroflections and on their duration. The fortuitous presence at sea of a research vessel has now enabled us to investigate such an episode at subsurface levels in combination with remote sensing of the sea surface. We present here the first in situ evidence that an upstream or early retroflection can extend to a depth of well over 750m and last for 5 months. This event was likely triggered upstream by the happenstance of two Natal Pulses, large cyclonic eddies inshore of the Agulhas current. These eddies short-circuited the Agulhas with its Return current, leading to the shedding of three large Agulhas rings in quick succession. The arrival of a third cyclonic eddy when the Retroflection was still quite retracted did not lead to another ring shedding event. The resulting early retroflection may have had the effect of stalling the shedding of Agulhas rings and their motion towards the Cape Basin. However, these early retroflections are too scarce to allow generic statements on their generation or consequences, and the relation with large-scale environmental factors. It is likely that the observed withdrawal of the retroflection into the Transkei Basin is a fortuitous result of a series of contingent interactions.
► A very early retroflection of the Agulhas current was formed after shedding off three Agulhas rings. ► This retracted retroflection moved west in the following 5 months without ring shedding. ► The subsurface retroflection agrees with RS images of SST and SSH. ► The Agulhas retroflection extends to a depth of at least 750m, and likely deeper. ► The early retroflection is a scarce and contingent phenomenon, mainly governed by chance.
Emotional experience is stored within the amygdala and the limbic system of the brain as affect, visceral, and physiological sensation without symbolization and language. These significant memories ...are expressed in affect and through our bodily movements and gestures. Such body memories are unconscious non-symbolized patterns of self-in-relationship. Several methods of a body centered psychotherapy are described and clinical case examples illustrate the use of expressive methods within a relational psychotherapy.
ARGO hydrographic profiles, two hydrographic transects and satellite measurements of air–sea exchange parameters were used to characterize the properties and seasonal heat budget variations of the ...Surface Mixed Layer (SML) south of Africa. The analysis distinguishes the Subtropical domain (STZ) and the Subantarctic Zone (SAZ), Polar Frontal Zone (PFZ) and Antarctic Zone (AZ) of the Antarctic Circumpolar Current. While no Subantarctic Mode Water forms in that region, occurrences of deep SML (up to ∼450 m) are observed in the SAZ in anticyclones detached from the Agulhas Current retroflection or Agulhas Return Current. These are present latitudinally throughout the SAZ, but preferentially at longitudes 10–20° E where, according to previous results, the Subtropical Front is interrupted. Likely owing to this exchange window and to transfers at the Subantarctic Front also enhanced by the anticyclones, the SAZ shows a wide range of properties largely encroaching upon those of the neighbouring domains. Heat budget computations in each zone reveal significant meridional changes of regime. While air–sea heat fluxes dictate the heat budget seasonal variability everywhere, heat is mostly brought through lateral geostrophic advection by the Agulhas Current in the STZ, through lateral diffusion in the SAZ and through air–sea fluxes in the PFZ and AZ. The cooling contributions are by Ekman advection everywhere, lateral diffusion in the STZ (also favoured by the ∼10° breach in the Subtropical Front) and geostrophic advection in the SAZ. The latter likely reflects an eastward draining of water warmed through mixing of the subtropical eddies.
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