Bathymetry ; Black Sea ; Current ; Echosounding ; Flood ; Holocene ; Marine quaternary ; Palaeo-environment
by bottom currents. The easterly flowing currents inferred to have formed the hills may be related to a catastrophic flood of the Black Sea from the Sea of Marmara 7150 yr ago.
Echo-sounding data recorded in the Black Sea in 1969 imaged a chain of hills 5- to 150-m high at a depth of 2000-2200 m that resemble hills on the lower continental rise. Like those hills, the features in the western Black Sea may have been created
A simple model for current speed in tidal channels
Coastal environment ; Denmark ; Hydrodynamics ; Model ; Sea level ; Storm ; Tidal creek ; Tidal current ; Wind
in the Danish Wadden Sea. This type of model can be used to extend and/or complete time series of current speed in a particular tidal channel and to make quick estimates of the current speed, with a minimum of information and CPU consumption.
This paper presents a simple non-distributed, PC-based model describing current speed in a tidal channel based on the continuity equation with tide gauge water level as the only time dependent input parameter. This model is tested in a tidal channel
This study presents results on sedimentation fluxes obtained during deployments of a tripod equipped with sediment traps and instruments for measuring wave and current parameters in each of two environments (Løgstør Broad and Amstrup Bay), dominated
Coastal environment ; Indian Ocean ; METEOSAT ; Marine hydrology ; Meander ; NOAA ; Ocean atmosphere interaction ; Remote sensing ; Seacurrent ; South Africa
The role played by large solitary meanders on the flow of the Agulhas Current is reviewed and a tentative classification of meander types is proposed. - (AJC)
Three sediment cores on a transect across the continental slope off Namibia at about 23°S were investigated for alkenone-derived past sea-surface temperature (SST) and total organic carbon (TOC) content. These records are used to reconstruct
variations of surface circulation, coastal upwelling, and paleoproductivity in the northern Benguela Current System for the last 150,000 yr.
Data collected in the nearshore region between Point Lay and Icy Cape, Alaska, support the thesis that a well-developed coastal jet is present during the summer. The temporal variability of the current is as predicted by theory. The physical
characteristics of the region suggest a strong signal-to-noise ratio for the baroclinic coastal jet. It is probably the dominant mode of summer coastal circulation for the entire Chukchi Sea coast of the Alaskan North Slope.
Mean sea level variations and their practical applications
Daily mean sea-level time series recorded in Naples (1959-1976) and the joint variation of sea-level, atmospheric pressure and wind together with the values of water density and marine currents are analyzed. An autoregressive model for mean sea
Simulation of the sea-breeze front with a model of moist convection
Even with a weak offshore background wind, the sea-breeze rapidly takes the form of a gravity current, with a well-defined head. The formation of clouds tends to strengthen the sea-breeze. The reason is that convective clouds form on the landward
side of the sea-breeze front, and evaporate at the seaward side. This implies the existence of an additional horizontal gradient in diabatic heating. (JPB).
Coastal current ; Coastal environment ; European part of Russia ; Kaliningrad ; Marine sedimentation ; Sediment transport
within convergence zones of the energetic currents, and by longshore gradient currents resulting from the water surface denivelations due to wave transformations over the sea floor elevations. - (L'Ed.).
place in heads of bights. Several stable lithodynamic cells have been identified; exchange of energy and sediments between them is hampered. The sediment transport within each cell is effected by longshore energetic currents, rip currents developing
Direct measurements of seabed stress are difficult, especially in field conditions. Several methods for estimating these stresses using current meter data are available. Two of these methods, the Inertial Dissipation Method and the Turbulent Kinetic
Energy Method, are described, and a Matlab program is used to analyse data from a wave-current environment.
The AA. examine multibeam sonar datasets from areas of extreme tidal currents to see if there is any evidence for erosion of bedrock. A dataset of shear stresses beneath typically strong tidal currents is developed and compared with a dataset
for bedrock-eroding rivers. In the Minas Passage (Bay of Fundy), Canada, the Bristol Channel off Nash point, UK, and in the Straits of Messina, Italy, sonar data are collected and discussed. Holocene tidal currents have apparently been generally ineffective
at eroding bedrock. The AA. examine this issue further by compiling extreme tidal streams around the UK and from them estimate shear stresses, representing a macro-tidal environment where peak surface currents reach 9-7 knots. Those data are compared
Chile ; Deglaciation ; Diatom ; Holocene ; Oceanology ; Pacific Region ; Seacurrent ; Surface temperature ; Upwelling
A geochemical and paleontological reconstruction of paleoproductivity, upwelling intensity and sea surface temperature (SST) off central Chile at 35°S reveals marked changes from the Last Glacial Maximum (LGM) through the Early Holocene. The AA
. discuss their observations in the context of the Southern Westerlies and the subtropical high-pressure belt, the main forcing for paleoproductivity changes in the southern part of the Peru-Chile Current.
The greenhouse effect, climatic change and rising sea level : implications for development
Climatic variation ; Development ; Forecast;Prediction ; Global change ; Greenhouse effect ; Human impact ; Sea level ; Third World
The AA. elaborate on the scientific basis underlying the greenhouse effect, climatic change and sea level rise, following by the implications for development. As well as presenting best current scientific judgements, they shall highlight major
Sediment transport across a tidal divide in the Danish Wadden Sea
Coastal environment ; Denmark ; Estuary ; Hydrodynamics ; Model ; North Sea ; Sediment transport ; Spatial variation ; Suspended load ; Tidal current ; Tide
The aim of this study is to examine the spatial and temporal variation of water and sediment transport across a tidal divide in the Danish Wadden Sea. This is exemplified by 2 low-energy and 2 high-energy case studies selected from a 2-month