explaining the weddell polynya a large ocean eddy shed at maud rise satellite observations have shown the occasional occurrence of a large opening in the sea ice cover of the weddell sea antarctica a phenomenon known as the weddell polynya the transient appearance position size and shape of the polynya is explained here by a mechanism by which modest variations in the large scale oceanic flow past the maud rise seamount cause a horizontal cyclonic eddy to be shed from its northeast flank the shed eddy transmits a divergent ekman stress into the sea ice leading to a crescent shaped opening in the pack atmospheric thermodynamical interaction further enhances the opening by inducing oceanic convection a sea ice ocean computer model simulation vividly demonstrates how this mechanism fully accounts for the characteristics that mark weddell polynya events

atmospheric input of trace metals to the western mediterranean sea 1 factors controlling the variability of atmospheric concentrations the factors controlling the variability of atmospheric trace metal concentrations over the western mediterranean sea have been investigated using a combination of geochemical and meteorological approaches al br cd na pb and 210po concentrations from bulk filters and cascade impactor samples collected during five cruises 1980 1983 have been used to characterize the aerosol sources the marine source na the aeolian soil mobilization al the anthropic sources cd pb and the volcanic source 210po it has been confirmed that cd and pb directly derive from anthropic sources as shown by three dimensional air mass trajectory analyses the variability of daily atmospheric concentrations reflects both changes in continental source strengths and in airflow patterns atmospheric concentrations appear to be higher during episodes of short range transport of continental material from riparian countries it is suggested that such source regions can be precisely identified by a careful examination of both geochemical data and three dimensional trajectories from our data set southwestern europe would be responsible for the largest pb and cd inputs to the western mediterranean atmosphere 30 40 but the inputs from north africa are also likely to be significant 20 25 however it cannot be ascertained whether this conclusion is valid on a yearly time scale indeed whereas our sample set is representative of the yearly airflow climatology it has not been possible to assess the effect of seasonal for pb or sporadic for al changes in source strengths this points out that over such a marine environment continuous sampling programs are needed to assess the respective contributions of individual source regions to the atmospheric burden of particulate trace elements

a series of cyclonic eddies in the antarctic divergence off adelie coast 1 the spatial and temporal characteristics of cyclonic eddies in the antarctic divergence off adelie coast are described using repeated in situ observations between 2001 and 2003 satellite observations and results of a high resolution ocean general circulation model satellite ocean color images and altimetry clearly revealed a series of cyclonic eddies with diameters of about 100 150 km that were separated by about 150 km in the zonal direction the eddies are found at almost the same locations and can be traced for at least two months in the spring summer period cold and fresh anomalies were found throughout the water column in the cores of the cyclonic eddies the water properties in the core of the eddies are similar to water found over the continental slope 150 200 km to the south the geopotential anomaly of the cold features was smaller than the sea level anomaly detected with satellite altimetry indicating that significant barotropic flow is associated with the eddies the ocean general circulation model for the earth simulator ofes reproduces a series of cyclonic eddies similar to those observed including a significant barotropic component in the model the series of eddies appear to originate further west over the continental slope region with no consistent phase propagation the combination of repeat in situ observations remote sensing and high resolution model results confirms the existence of persistent cyclonic eddies near 140 e and suggests the eddies play an important role in the exchange of water across the antarctic divergence

simulations of northern hemisphere ice sheet retreat sensitivity to physical mechanisms involved during the last deglaciation a 3 dimensional thermomechanical ice sheet model is used to simulate the evolution of the geometry of northern hemisphere ice sheets through the last deglaciation the ice sheet model is forced by a time evolving climatology provided by the linear interpolation through time of climate snapshots simulated by the lmd5 3 atmospheric general circulation model agcm at different periods of the last deglaciation 21 15 9 6 and 0 kyr bp the agcm is driven by insolation atmospheric co2 content ice sheet configuration and sea surface temperatures although our approach is able to produce the complete continental ice retreat our simulated deglaciation presents a phase lag with reconstructions based on observational evidences this suggests that physical mechanisms related to climate forcing and or ice sheet internal dynamics are not properly represented the influence of millennial scale forcing feedback mechanisms between ice sheet elevation and surface mass balance and parameterization of the ice flow is also tested through a set of sensitivity experiments the rapid variability has a strong impact on the evolution of the ice volume because of nonlinear effects in temperature mass balance relationships fennoscandia appears to be strongly sensitive to the small scale ice sheet instability both ice sheets are to some extent sensitive to an increased basal sliding

discovery of an anoxic basin within the strabo trench eastern mediterranean we report here the discovery of a basin which we call the tyro basin in the eastern mediterranean in which anoxic conditions exist and organic rich sediments are accumulating bottom water samples show extremely high salt concentrations a horizontal midwater sound reflector about 70 m above the basin floor was observed in a seismic reflection profile across the basin from shipboard observations we conclude that dissolution of messinian evaporites exposed by faulting in the sides of the basin causes stagnant bottom conditions this basin provides an opportunity to test some of the hypotheses concerning the formation of sapropels present in cores collected from the same area cores taken in an adjacent similar basin for which we propose the name kretheus basin indicate a recent change from anoxic to oxygenated conditions which was probably caused by tectonic activity associated with the strabo trench

zr hf ratio and ree behaviour a coupled indication of lithogenic input in marginal basins and deep sea brines abstract the distribution of dissolved zr hf and rare earth elements yttrium and lanthanides hereafter referred to as ree in the eastern mediterranean seawater column was measured in the kryos basin to evaluate the lithogenic contribution from both nile river and sahara and arabian desert dust we found dissolved zr hf ratios below the signature of crustal rocks and chondrites a phenomenon likely driven by the dissolution of the mn rich coating of atmospheric dust particles delivered from the desert in deeper waters zr hf ratios are clustered close to the signature of crustal rocks and chondrites according to the different zr and hf dissolved speciation the zr hf ratio observed in the deeper 3300 m seawater column corresponds to the value found in the atlantic ocean the ree distribution displays a negative ce anomaly and a positive la anomaly throughout the shallow waters above a 75 m depth zr hf and ree concentrations measured in the anoxic deep sea brines from tyro medee and thetis basins indicate that the dissolution of evaporite within messinian levels is responsible for the high salt content of these brines and influence zr hf fractionation in the aqueous phase hafnium shows stronger affinity relative to zr for surfaces of salts and mn fe oxyhydroxides zr hf values and the observed shale normalised ree features suggest that zr hf and ree are leached from mn and fe rich coatings of desert particles in shallow water layers this process can be responsible for the observed distribution of studied elements in the studied eastern mediterranean oxic seawater in deep sea brines zr hf and ree are released from messinian evaporites

entrainment of trace metal enriched atlantic shelf water in the inflow to the mediterranean sea surface waters of the mediterranean sea have higher trace metal concentrations than open atlantic surface waters1 this observation could be explained by sources within the basin but recent data from the alboran sea2 indicate that trace metals may already be enriched in atlantic waters flowing into the mediterranean through the strait of gibraltar here we present new data documenting the presence of trace metal enriched source waters west of the strait and present a mathematical analysis showing that cu ni cd and zn distributions in the alboran sea can be explained as linear mixtures of four well defined sources 1 spanish coastal waters 2 north atlantic central water 3 atlantic surface water and 4 mediterranean levantine intermediate water in this analysis salinity and trace metals are used for the first time to deconvolve mixing between water masses of different origins

trace metal distributions in seawater and anoxic brines in the eastern mediterranean sea abstract the vertical distribution of dissolved and particulate trace metals mn fe ni cu cd is reported for seawater and the anoxic brines of tyro and bannock basins in the eastern mediterranean in normal mediterranean seawater the distribution of dissolved trace metals is governed by water mass circulation as well as by local input sources for cd and possibly cu steady state behaviour is not a viable assumption probably as a result of anthropogenic sources in agreement with previous reports no correlation was observed between dissolved ni cu cd and the major nutrients at the seawater brine interface all trace metals show dramatic changes in concentration in the brines the concentrations of dissolved fe and mn are strongly elevated compared to overlying waters yet probably limited by formation of solid sulfide and or carbonate phases the distributions of dissolved fe and sulfide show a remarkable mirror image of those found previously in the orca brine gulf of mexico and the ionic concentration products are approximately the same in all three basins the difference in absolute fe and sulfide concentrations is thought to be caused by a high supply of fe to orca basin concentrations of dissolved ni cu and cd in the brines are at least one order of magnitude lower than in overlying waters most likely due to formation of solid sulfide phases we believe these data provide the first indication of substantial nickel sulfide co precipitation within an anoxic basin particulate metal concentrations are elevated at the seawater brine interface and are probably associated with the presence of solid sulfide phases in addition the extreme density gradient at the interface will slow the sinking rate of particles and lead to accumulation of particles at the interface due to accumulation

geochemical and sedimentological considerations of a permanently anoxic fjord framvaren south norway abstract framvaren a fjord in south norway is an example of extreme anoxia due to the geomorphological features sill depth 2 m basin depth 180 m the postglacial history of framvaren is outlined emphasizing the preservation of environmental changes in the properties of the water and the sediments high levels of hydrogen sulfide in the water 170 180 ml l 1 or 7 8 mm h 2 s dense populations of photosynthetic bacteria at the redox boundary total number 3 10 6 ml 1 metal sulfide formation in the anoxic water e g framboidal pyrite and zinc sulfide and organic rich bottom sediments with high metal content e g 1000 ppm zn are typical examples the rate of sedimentation is estimated in three independent ways suggesting an average annual flux of 100 g m 2 yr 1 in the central basin of framvaren fluxes of organic matter and zinc to the sediments are calculated and compared with potential sources

the contrasting biogeochemistry of iron and manganese in the pacific ocean abstract vertical and horizontal distributions of dissolved and suspended particulate fe and mn and vertical fluxes of these metals obtained with sediment traps were determined throughout the pacific ocean in general dissolved fe is low in surface and deep waters 0 1 to 0 7 nmol kg with maxima associated with the intermediate depth oxygen minimum zone 2 0 to 6 6 nmol kg vertical distributions of dissolved mn are similar to previous reports exhibiting a surface maximum a subsurface minimum a mn maximum layer coincident with the oxygen minimum zone and lowest values in deep waters near shore removal processes are more intense for dissolved fe than for dissolved mn dissolved mn in the surface mixed layer remains elevated much farther offshore than dissolved fe elevated near surface dissolved mn concentrations occur in the north pacific equatorial current suggesting transport from the eastern boundary near surface mixed layer dissolved mn concentrations are higher in the north pacific gyre reflecting enhanced northern hemisphere aeolian sources residence time estimates for the settling of refractory paniculate fe and mn from the upper water column are 62 220 days fe and 105 235 days mn in contrast residence times for the scavenging of dissolved fe and mn are 2 13 years fe and 3 74 years mn scavenging residence times for dissolved mn based on horizontal mixing in the surface mixed layer of the northeast pacific are 0 4 years nearshore to 19 years 1000 km offshore there is no evidence for in situ fe redox dissolution within sub oxic waters in the eastern tropical north pacific dissolved fe appeared to be controlled by dissolution from sub oxic sediments with oxidative scavenging in the water column or upper sediment layers however in situ mn dissolution within the oxygen minimum zone was evident

trace metal speciation in sea and pore water of the gotland deep baltic sea 1994 abstract studies on the speciation particulate colloidal anionic and cationic forms of trace metals cd co cu fe mn mo ni pb zn in the water column and in pore waters of the gotland deep following the 1993 94 salt water inflows showed dramatic changes in the total dissolved metal concentrations and in the ratios between different metal species in the freshly re oxygenated waters below 125 m changes in concentrations were greatest for those metals for which the solubility differs with the redox state fe mn co but were also noted for those metals which form insoluble sulphides cd pb cu zn and or stable complexes with natural ligands cu pore water data from segmented surface muds 0 200 mm indicated that significant redox and related metal speciation changes took place in the surface sediments only a few weeks after the inflow of the oxygenated sea water into the gotland deep

on mertz and ninnis glaciers east antarctica two large glacier tongues which extend substantially across the coastline of king george v land in east antarctica have been studied by remote sensing synthetic aperture radar jers 1 the tongue of mertz glacier is in a state of advance while the ninnis glacier tongue is retreating some more specific points are the distinctive surface structure and the form of the glacier tongues indicates that they are floating while the tongue of ninnis glacier has lost about two thirds of its area since 1913 the mertz glacier tongue has advanced substantially and has about doubled its areal extent over the same time period the annual movement of the tongue of mertz glacier was determined as about 1 2 km this is close to the value of the advance of the tip of the tongue since 1963 which was determined as 0 9 km year 1

trace metal enrichments in the mediterranean sea copper nickel and cadmium occur at higher concentrations in the surface waters of the mediterranean than in nutrient depleted waters of the open ocean trace metal profiles have been taken on both sides of the strait of gibraltar to constrain a mass balance deep mediterranean waters have trace metal levels comparable to surface waters in regions of mediterranean deep water formation implying a minimal role for vertical transport by biological activity excess trace metals are not present in open atlantic source waters but a detailed map of trace metal distributions in the alboran sea immediately east of the strait reveals a metal enriched plume with concentrations as high as copper 3 6 nmol kg nickel 2 8 nmol kg and cadmium 120 pmol kg a substantial enrichment in trace metal concentrations therefore can occur in transit from the open atlantic through the coastal zone into the strait this trace metal enrichment may derive either from river inflow masked by evaporation diffusion out of continental shelf sediments eolian particulate fallout or anthropogenic sources metal sources fluvial sedimentary or atmospheric natural or anthropogenic are difficult to discern from the large scale oceanographic distribution metal retention in nutrient depleted surface waters is not due to unusual metal fluxes relative to nutrients but instead is a consequence of less frequent recycling of nutrients in the mediterranean compared to the open ocean metal enrichments would be expected before human intervention with anthropogenic input reflected in proportion to the relative augmentation of inputs over natural levels mediterranean water produces small trace metal anomalies in the outflow core positive for ni negative for cd present observations are consistent with this prediction but high precision data would be necessary to observe these at distance from gibraltar

eddies revealed by seawifs ocean color images in the antarctic divergence zone near 140 e 1 eddy like distributions of chlorophyll a were clearly detected in the antarctic divergence zone around 140 e by seawifs ocean color images the distribution was also supported by in situ measurements the eddy like structure was associated with changes in surface and subsurface water mass properties extremely high levels of chlorophyll in coastal areas were transported and redistributed horizontally offshore by these eddies and a significant effect of the huge biomass on the biological processes in the investigated area was expected the lateral exchange between coastal and offshore waters driven by these eddies may be an essential factor in the observed patchy structures in this region

chemical and isotopic 87sr 86sr δ18o δd constraints to the formation processes of red sea brines abstract about twenty deeps filled with hot brines and or metalliferous sediments are located along the red sea axis these brines present a well suited framework to study the hydrothermal activity in such a young ocean the present study outlines the results of a geochemical approach combining major trace element and isotopic oxygen hydrogen strontium analyses of brines in six of the deeps to evaluate different processes of brine formation and to compare the evolution of each deep important heterogeneities in temperature salinity hydrographic structure and chemistry are recorded each brine having its own characteristics the intensity of hydrothermal circulation varies among the deeps and ranges from being strong atlantis ii and nereus to weak port soudan and even to negligible valdivia and suakin and it varies along the entire red sea axis these observations do not favour a unique formational model for all of the brines for example the brines of the suakin deep appear to have been formed by an old sea water which dissolved evaporite beds without significant fluid circulation and hydrothermal input while others such as atlantis ii or nereus deeps appear to be dominated by hydrothermal influences a striking feature is the absence of a relationship between the position of the deeps along the axis and their evolutionary maturity

dissolved aluminium in the mediterranean abstract three vertical profiles of dissolved al and nutrients are reported from the eastern basin of the mediterranean profiles of al concentrations resemble those of the nutrient elements except that a proportionally higher residual concentration remains in the surface layer concentrations of al in the surface water inflow from the north atlantic which contains between 10 and 20 nm around gibraltar are elevated to 55 59 and 75 nm at the stations occupied calculations indicate that these concentrations are probably produced by dissolution al from aeolian dust and advective mixing of al rich deep waters into the surface layer balanced by a biologically associated removal process the al removed from the surface layer redissolves in the deep water to raise al concentrations to about 160 nm samples were also recovered from anoxic deep brines in the tyro and bannock basins in the brines al concentrations fall to about 15 nm while si concentrations approach 270 nm

sulphur speciation in anoxic hypersaline sediments from the eastern mediterranean sea abstract the anoxic hypersaline tyro and bannock basins are among the most sulphidic bodies of water in the marine environment h2s 2 mm we report the distribution of elemental sulphur acid volatile sulphur avs organic polysulphides humic sulphur 0 5 m naoh extractable and pyritic sulphur in the sediments from these basins pyritic sulphur appears to be the main phase of inorganic reduced sulphur 50 80 of the total sulphur pool and is at the same level about 250 moles per gram dry weight in cores recovered from the two basins remarkably humic sulphur has been found to account for 17 28 of the total sulphur pool in the tyro basin and for 10 43 in the bannock basin sulphur isotope data show negative 34s values for both pyritic sulphur 34s 19 c to 39 and humic sulphur 34s 15 to 30 this indicates that both pyritic and humic sulphur originate from microbially produced hzs neither basin shows a significant correlation between pyritic sulphur and organic carbon suggesting syngenetic pyrite formation additionally the degree of pyritization in these sediments dop is 0 62 indicates that pyrite formation is limited by the reactivity of fe humic sulphur correlates with the pyritic sulphur distribution and seems to be related with gelatinous pellicles bacterial mats at the interface between oxic seawater and brine both pyritic and humic sulphur can be formed in the water column at the interface of oxic seawater and brine by a syngenetic pathway about 5 of the pyrite is formed in the sediments by diagenetic processes the presence of a bacterial mat and high hzs content in the brines favour such conditions however most of the humic sulphur inventory can be supported by diagenetic processes although these basins differ in their major element chemistry their reduced sulphur species chemistry appears to be similar

a latent and sensible heat polynya model for the north water northern baffin bay abstract the pease latent heat polynya model is coupled to a reduced gravity coastal upwelling model in order to simulate the formation and maintenance of the north water now the arctic s largest polynya located in northern beffin bay in this region strong northerly winds during winter and spring drive ice southward as fast as it is produced locally the pease mechanism for polynya formation and also produce upwelling of warm subsurface water along the west coast of greenland this upwelling provides an upward heat flux that melts ice near the coast a sensible host mechanism for polynya formation this combined latent and sensible heat polynya model is formulated as an initial boundary value problem with uniform winds its solution gives the tide evolution of the upper layer velocity and depth and also the polynya width as measured southward from the northern boundary of the polynya there are two fundamental time scales in the problem a fast one of the order of days that characterizes the

alkali elements na k rb and alkaline earth elements mg ca sr ba in the anoxic brine of orca basin northern gulf of mexico abstract a profile of filtered seawater and brine samples was collected in the summer of 2003 from a depth of 1500 m down to the bottom of the anoxic hypersaline orca basin northern gulf of mexico using ion chromatography and inductively coupled plasma mass spectrometry icp ms these samples were analyzed for alkali cations na k rb alkaline earth cations mg 2 ca 2 sr 2 ba 2 and the major anions chloride cl and sulfate so 4 2 major ion concentrations in the brine are consistent with previous studies confirming that na plus cl make up more than 95 of its composition hence governing its density and hydrodynamic stability binary mixing plots across the interface between deep gulf of mexico seawater and the anoxic brine are generally linear but display substantial deviations from conservative behavior at the steepest part of the pycnocline for all analytes except na cl and ca negative deviations signify localized cation removal by an adsorption or ion exchange process probably associated with the dense layers of particles that are trapped there especially strong mg removal may be indicative of dolomitization whereby the concomitant release of ca counters its adsorption resulting in zero net ca removal a positive deviation for sulfate is attributed to bacterial sulfide oxidation concentrations of rb sr and ba in the homogeneous brine reported here for the first time are enriched by factors of 1 5 1 4 and 9 respectively with respect to the overlying seawater unlike ca and sr ba concentrations in the brine are clearly controlled by the solubility of its sulfate salt barite causing a maximum of 670 nmol kg at the interface several independent lines of evidence suggest that the brine is formed outside the basin most likely by the interaction of seawater with regionally extensive evaporite deposits a simple mass balance shows that the dissolution of about 280 g of halite per kg of seawater can account for the extreme concentrations of na and cl in the orca basin brine the same mass balance was applied to a number of minor constituents k rb mg ca sr so 4 br total iodine in order to calculate what abundances in the halite are required to reproduce their concentrations in the brine as measured in the present work and by others the results are entirely compatible with the composition of the jurassic louann salt specifically with the median of compositions published for a transect spanning early to late stage halites elevated abundances of k and rb point to contributions from bittern facies modified by prior diagenetic contact with seawater

the distribution and formative processes of latent heat polynyas in east antarctica a study of polynya characteristics in east antarctica was undertaken using ice concentrations derived from special sensor microwave imager data for the period july 1987 august 1994 the areas of polynyas were defined as having an ice concentration 75 the analysis revealed a total of 28 coastal polynyas within the study region the spatial and temporal variability in areal extent was quantified the timing of mean maximum areal extent varied from june to october the bathymetry and wind regime at each polynya site was examined to gauge the relative importance of these parameters in polynya formation and maintenance in 20 locations shallow banks and shoals form grounding zones for icebergs and anchoring sites for fast ice which form barriers to the predominantly westward drift of the pack ice elsewhere north south coastal protrusions or alignments form similar barriers the subsequent removal of newly formed sea ice from the lee of such barriers by katabatic and synoptic winds maintains areas of reduced ice concentration and open water very few coastal polynyas are attributed solely to katabatic outflow the combined influence of bathymetry topography and winds is responsible for the characteristics of the majority of polynyas many were considered to be marginal characterised by occasional periods when the ice concentration falls below 75 an analysis of annual winter totals of areas with ice concentrations 75 shows no trends in total polynya areal extent over the period 1987 94 known locations of emperor penguin aptenodytes forsteri rookeries were also found to be associated with the locations of coastal polynyas

biogenic hydrocarbon gases and sulfate reduction in the orca basin brine the composition of light hydrocarbon gases in the orca basin an anoxic hypersaline intraslope depression on the continental slope of the northern gulf of mexico indicates that both methane and ethane are biogenic in nature with a c1 c2 c3 ratio of 730 and a 13c of methane of 73 relative to the pdb standard the concentrations of methane 750 mm and ethane 1300 mm in the orca basin brine are higher than any other marine anoxic basin these high levels result not from high rates of productivity but from the long residence time of the brine in the basin due to its high stability toward mixing with overlying seawater 1 z 3 2m both methane and ethane show well mixed distributions in the brine these distributions probably result from convective mixing of the isohaline brine pool due to normal heat flow from the basin sediments methane and ethane maxima above the pycnocline at the brine seawater interface reflect in situ production and or consumption in the aerobic water column concurrent maxima in suspended particulate material distributions in this region suggest methane may be produced there in anaerobic microenvironments associated with the suspended matter reduced rates of anaerobic decomposition including sulfate reduction in the brine sediments are inferred from preserved sargassum fronds in the sediments vertical sulfate profiles in most cores and the sediment organic carbon content which is two to three times higher in sediments below the high salinity brine than in the normal gulf sediments nearby

vertical distributions and speciation of dissolved rare earth elements in the anoxic brines of bannock basin eastern mediterranean sea abstract vertical distributions of dissolved rare earth elements rees are presented for the anoxic highly sulfidic brines of bannock basin in the eastern mediterranean sea ree concentrations at the seawater brine interface are the highest ever recorded in the water column of an anoxic basin and comparable only to ree concentrations at depth in the porewaters of reducing sediments below the seawater brine interface throughout the upper of two chemically distinct brine layers ree concentrations decrease with depth as a result of scavenging while shale normalized ree patterns are characterized by little or no fractionation between the light rees lrees and the heavy rees hrees and by a positive ce anomaly throughout the lower of the two brine layers ree concentrations are constant while ree patterns are characterized by the same lack of lree or hree enrichment as well as by the absence of any ce anomaly a pronounced ree minimum at the interface between the two brine layers is apparently caused by uptake into dolomite that is formed through in situ recrystallization of ca carbonate a process that was previously reported to cause similar minima for mn and fe calculations of ree speciation incorporated into a model of ree scavenging developed by byrne and kim 1990 which uses ree complexation by monocarboxylic acids to represent ree adsorption onto particulate matter are surprisingly successful at reproducing the unusual shape of ree patterns in the brine this suggests that this shape although very different from that of ree patterns in the overlying seawater due to the very high ionic strength of the brine is the result of much the same processes that constitute ree scavenging in the open ocean

temperature structure and characteristics appearing on ssm i images of the cosmonaut sea antarctica water temperature structure in the cosmonaut sea at 60 68 s 35 65 e in 1987 92 shows that cold water with a temperature below 1 5 c was present in the coastal region the circumpolar deep water with a temperature higher than 1 0 c was found below about 150m depth from northeast to northwest of the cold water area the ssm i images in 1987 91 indicate that polynya activities were intensive in 1988 and the typical cosmonaut polynya was observed due to weaker activities the small and sporadic cosmonaut polynya formed in 1987 1989 1990 and 1991 a coastal polynya was frequently observed every year at about 66 s 50 60 e a train of polynyas to the east of cosmonaut polynya often appeared it is considered that the atmospheric convergence line and antarctic divergence region are responsible for polynya activities in the cosmonaut sea

effect of isostasy on dynamical ice sheet modeling a case study for eurasia 1 isostatic adjustment is an important process when modeling dynamical ice sheet evolution a number of different types of earth model are used to model this process ranging from models with local or elastic lithospheres with a single relaxation time to account for temporal behavior to self gravitating spherically symmetric models of the crust mantle system we performed sensitivity tests to assess the dynamical response of ice sheets to isostatic adjustment the resulting ice sheet geometries depend on the response times of the system including the growth rate of ice sheets versus the relaxation time of the earth differences in lithospheric strength cause large differences in the modeled ice sheets with the largest differences in isostatic adjustment in the vicinity of the ice margins in addition we compared predictions based on an often used flexural model with an elastic plate and a single relaxation time to a spherically symmetric self gravitating viscoelastic approach no flexural model was able to reproduce the viscoelastic response completely due to the fact that the models have an intrinsically different spatial and temporal response when applied to a full transient glacial cycle in eurasia even the best fitting flexural model underestimated the ice volume at the lgm by 30 percent our results indicate that the commonly used value of 3000 years for the relaxation time in flexural models is too short for eurasia by at least 3000 years

observations of a street of cyclonic eddies in the indian ocean sector of the antarctic divergence hydrographic and drifting buoy data from japanese cruises show that the antarctic divergence in the indian ocean sector is composed of a street of cyclonic eddies these eddies measure about 500 km in the zonal direction and 200 km in the meridional part of the eastward flowing antarctic circumpolar current acc meanders southward in the regions between the eddies in the eddy regions warm saline circumpolar deep water is upwelled into the shallow layers while cold dense coastal water advects into the deep layers the advection occurs along the isobaths of ridges which extend north from the coast the combination of the advection with the upwelling produces a water column denser than the surrounding water and leads to the formation and maintenance of the cyclonic eddies presence of the northward extending ridges approximately governs the location of eddy formation the eddy formation recurs year after year although eddy locations can vary somewhat a polynya was observed to persistently occur and corresponded with one of the eddies in location size and form the oceanographic observations also suggest that the primary meridional exchanges of heat and salt in the antarctic are caused through the eddies and acc meanders within the antarctic divergence

extremely low oxygen concentration in mid proterozoic shallow seawaters abstract the mid proterozoic 1 8 0 8 ga witnessed the first appearance but unusually low diversification of eukaryotes the stagnant biotic evolution during this billion year long period commonly referred to as the boring billion was arguably ascribed to low oxygen levels in atmosphere and ocean however evidence supporting low oxygen in shallow marine environments where early eukaryotes first evolved is generally lacking or insufficient here we report rare earth element and yttrium ree y data particularly cerium ce anomalies from a suite of mid proterozoic sedimentary rocks of the north china platform the new data from north china in combination with available ce anomaly data from other proterozoic successions demonstrate that during mid proterozoic negative ce anomalies did not occur until 1 54 ga and after 1 54 ga only episodic negative ce anomalies were present in shallow water carbonates trace element enrichments u ef v ef and mo ef remained at the average continental crust level before 1 54 ga but showed a sudden increase at 1 54 ga the data suggest that oxygen concentration in shallow marine environments of the mid proterozoic ocean was extremely low probably

gypsum precipitation from cold brines in an anoxic basin in the eastern mediterranean in 1968 hot brines from which gypsum had precipitated were discovered in the red sea in a divergent plate boundary setting with hydrothermal activity1 we now report the discovery of cold brines in an entirely different geodynamic situation a convergent plate boundary in the eastern mediterranean where the heatflow is very low2 and no hydrothermal activity occurs decimetric pure gypsum crystals precipitate from the cold brines which occupy the bottom of a rimmed anoxic basin near the southern edge of the mediterranean ridge close to the sirte abyssal plain nucleation of the crystals does not occur at the surface but from the deep brines because the salinity of the water is normal down to the depth of 3 000 m we propose the name bacino bannock for this basin after the consiglio nazionale delle ricerche r v bannock from which the bottom water brines were surveyed and sampled

the pattern and variability of antarctic sea ice drift in the indian ocean and western pacific sectors sea ice drift physically redistributes pack ice and changes ice extent concentration and through deformation the ice thickness distribution in this paper data are presented from 39 satellite tracked buoys deployed during various seasons from 1985 to 1996 in the sea ice of the southern ocean off east antarctica between 20 and 160 e longitude the dominant features of the ice motion in the region are a westward drift parallel to the bathymetry near the antarctic continent a cyclonic circulation cell in prydz bay and eastward drift of the ice to the north of the zonal shear zone the oceanic circulation along the coast is generally barotropic and the ice drift is well correlated with bottom topography northward outflows the locations of which are determined by both bottom topography and the seasonally varying position of the zonal shear zone allow the discharge of sea ice from the westward drift in the south into the northerly belt of eastward flow but with considerable variability in the net northward ice transport the ice translation monitored by the buoys is used to derive the spatial pattern of the ice velocity field the daily average ice drift speed in the westward flow is 0 23 m s 1 19 8 km d 1 with considerable spatial and temporal variability and in the eastward flow the average is 0 17 m s 1 15 1 km d 1 seasonal and interannual ice drift variabilities are analyzed the results are compared with satellite data of sea ice extent and concentration over the same time as well as with hydrographic observation of the position of the antarctic divergence

anoxic basins of the eastern mediterranean an overview it is well known that the mediterranean sea underwent several episodes of basin wide stagnation in the plio pleistocene but extant anoxic basins were first discovered between 1983 and 1984 in the strabo trench and in the southwestern slopes of the mediterranean ridge facing the sirte abyssal plain since then several expeditions were carried out to investigate the geology and physiography of the basins as well as the physical and chemical characters of the water column although the geodynamic settings of the tyro and bannock basins are quite different they are very deep closed and filled by dense salty cold brines whose presence is attributed to submarine dissolution of messinian evaporites bannock basin is interpreted as a collapse basin with a complex configuration central domes and several satellite basins most of which are anoxic unlike the tyro basin it is characterized by precipitation of gypsum occurring as euhedral crystals within the sediments and dredged along the steep wall bordering the main basin to the east the interface separating normal seawater from the brines corresponds to a well defined pycnocline with a density contrast of approximately 20 where strong bacterial activity seems to occur and a sudden decrease in transmittance is recorded studies on the water column document drastic changes of all the various parameters measured o2 h2s ca po4 ba across the interface sediments deposited beneath the brines are anoxic this kind of geologically induced anoxia is persistent and diachronous in contrast with the isochronous episodic repetitive and climatically induced anoxia recorded in the same area of the eastern mediterranean

a numerical study of dense water formation and transport on a shallow sloping continental shelf the circulation and transport of dense water generated by an idealized coastal polynya is studied using a three dimensional primitive equation model starting with a homogeneous quiescent ocean a constant negative buoyancy flux is imposed at the surface over a half elliptical region adjacent to the coastal boundary on a gently sloping continental shelf the flow response can be divided into the following three phases geostrophic adjustment instability and offshore eddy transport during geostrophic adjustment the fluid within the forcing region becomes denser and the flow at the edge of the forcing region accelerates in response to the strong density gradient there eventually the flow at the leading edge of the forcing region relative to kelvin wave propagation becomes unstable and a train of counterrotating eddies develops these eddies then form a complex three dimensional flow field and rapidly transport dense water offshore across isobaths the density within the forcing region reaches a maximum which remains fairly constant after the eddies begin to transport the dense fluid offshore the results are qualitatively insensitive to weakening of the negative buoyancy forcing and to changing the bottom slope eddy scales and velocities are consistent with observations in the arctic the results suggest that instability processes and eddy fluxes are important in transporting dense water off continental shelves and into marginal seas

ocean circulation and frontal structure near the southern kerguelen plateau the physical context for the kerguelen axis ecosystem study oceanographic observations from ships floats and remote sensing are used to describe the ocean circulation and frontal structure from the southern kerguelen plateau to the antarctic margin the flow of the antarctic circumpolar current acc is largely zonal upstream of the kerguelen plateau the southern branch of the polar front and the northern branch of the southern acc front saccf are deflected to the north by the topography and cross the plateau through the fawn trough the southern branch of the saccf and the southern boundary of the acc pass to the south of banzare bank through the princess elizabeth trough these fronts turn sharply to the north on the eastern flank of the plateau then retroflect to the south before continuing eastward satellite altimetry and float trajectories suggest the acc regime to the east of the plateau is eddy rich and characterised by extensive meandering of the acc fronts in contrast to the low eddy energy and zonal flow observed west of the plateau the antarctic slope current flows west along the upper continental slope with hydrographic data indicating some of the flow turns offshore and feeds the southern boundary flow in the western boundary current flow over the plateau itself is relatively quiescent and floats in this region have a long residence time 1 year the regional circulation is closely associated with the distribution of biological productivity in surface waters as revealed in satellite measurements of ocean colour including high productivity in subpolar waters along the eastern edge of the plateau and over the antarctic continental shelf moderate productivity over the plateau and low productivity in acc waters in the fawn trough and north of the saccf

copper isotope signatures in modern marine sediments abstract the development of metal stable isotopes as tools in paleoceanography requires a thorough understanding of their modern marine cycling to date no cu isotope data has been published for modern sediments deposited under low oxygen conditions we present data encompassing a broad spectrum of hydrographic and redox regimes including continental margin and euxinic sulphide containing settings taken together with previously published data from oxic settings these data indicate that the modern oceanic sink for cu has a surprisingly homogeneous isotopic composition of about 0 3 65cu relative to nist srm976 we suggest that this signature reflects one of two specific water column processes 1 an equilibrium isotope fractionation between soluble isotopically heavy cu complexed to strong organic ligands and an isotopically light pool sorbed to particles that deliver cu to the sediment or 2 an equilibrium isotope fractionation between the same isotopically heavy ligand bound pool and the particle reactive free cu2 species with the latter being scavenged by particulates and thereby delivered to the sediment an output flux of about 0 3 into sediments is isotopically light relative to the known inputs to the ocean at around 0 6 and the seawater value of 0 6 to 0 9 suggesting the presence of an as yet unidentified isotopically light source of cu to the oceans we hypothesize that this source may be hydrothermal or may result from the partial dissolution of continentally derived particles

dissolved iron in the cretan sea eastern mediterranean dissolved iron fe distributions in the water column of the cretan sea show consistent patterns of elevated surface mixed layer concentrations mean values of 1 44 and 1 95 nmol l 21 in march and september respectively that rapidly decrease with depth to low and relatively uniform concentrations in deep waters circa 0 5 nmol l 21 these features are consistent with inputs of dissolved fe to surface waters and with rapid scavenging to low values in deep waters the main source of surface dissolved fe is probably saharan atmospheric dust the supply of which is variable depending on sporadic dust storm events and transport to the cretan sea the short residence times estimated for dissolved fe in the mixed layer 0 7 2 yr emphasize the rapid removal of this element from surface waters and are consistent with recent mass balance calculations for fe in the western mediterranean sea in which rapid removal of fe to sediments is needed to provide a balance in the budget the deep water concentrations are strikingly constant and similar to or slightly lower than those reported for the open ocean the high surface concentrations we observed would be ample to support substantial primary production and it is likely that the macronutrients and phosphorus in particular limit production in this region iron fe is an essential nutrient for phytoplankton bacteria and other marine microorganisms and the role of this metal as a potentially limiting factor for phytoplankton has come under increasing scrutiny since the initial iron hypothesis was put forward by martin et al 1988 to explain limited productivity in high nutrient low chlorophyll hnlc oceanic systems experiments such as ironex and soiree have now clearly demonstrated that fe additions can stimulate phytoplankton growth in hnlc zones watson 2001 although many questions still remain about the forms of fe present uptake mechanisms and the impact of fe on export carbon production the distributions sources and sinks of fe in seawater have recently been reviewed de baar and de jong 2001 there is a coherent trend in reported data for all regions with increasing concentrations approaching the continental margins up to circa 100 nmol l 21 while in the open ocean dissolved fe has typically low concentrations in surface waters 0 02 1 nmol l 21 and higher 0 4 2 0 nmol l 21 concentrations in deep waters the rapid removal of dissolved fe through association with biotic and abiotic particles and its loss from the water column results in fe having a short residence time de baar and de jong 2001 and upper ocean concentrations should largely reflect local inputs e g aeolian and shallow benthic sourc1

on the circulation and water masses over the antarctic continental slope and rise between 80 and 150 e abstract the circulation and water masses in the region between 80 and 150 e and from the antarctic continental shelf to the southern boundary of the antarctic circumpolar current acc 62 s are described from hydrographic and surface drifter data taken as part of the multi disciplinary experiment baseline research oceanography krill and the environment broke two types of bottom water are identified adelie land bottom water formed locally between 140 and 150 e and ross sea bottom water ross sea bottom water is found only at 150 e whereas adelie land bottom water is found throughout the survey region the bottom water mass properties become progressively warmer and saltier to the west suggesting a westward flow all of the eight meridional ctd sections show an antarctic slope front of varying strength and position with respect to the shelf break in the water formation areas between 140 and 150 e and 104 e the antarctic slope front is more v shaped while elsewhere it is one sided the shape of the slope front and the presence or absence of water formation there are consistent with other meridional sections in the weddel sea and simple theories of bottom water formation gill 1973 deep sea research 20 111 140 whitworth et al 1998 in jacobs and weiss eds ocean ice and atmosphere interactions at the antartic continental margin antarctic research series american geophysical union washington pp 1 27 adcp surface velocities and buoy drift tracks show a strong westward flow over the shelf and slope regions in the region 90 100 e there is a strong eastward flow of the waters just south of the southern boundary of the acc suggesting a recirculation of the westward slope current and the presence of a weak cyclonic gyre using the adcp velocities as a reference for the ctd data the average westward transport in this region is 29 4 14 7 sv

modelling of last glacial maximum ice sheets using different accumulation parameterizations we use a three dimensional thermomechanical ice sheet model previously tested on the greenland ice sheet to reconstruct last glacial maximum lgm ice sheets we compare the effects on the results of the ice sheet model of three different accumulation parameterization schemes in the first and second schemes lgm precipitation is computed from the present precipitation taking and not taking into account moisture transport in the third scheme lgm precipitation and surface temperatures are computed using outputs of an atmospheric global circulation model agcm treated in anomaly mode results are compared to the last reconstruction of the northern hemisphere ice sheets peltier 1994 computed using global rebound rates in a visco elastic model of the earth s crust the first two accumulation parameterizations do not give satisfactory reconstructions of the lgm ice sheets since they are unable to compute realistic lgm climatic conditions the third method gives very satisfactory results which leads us to conclude that the best way to obtain realistic lgm climatic conditions is to use agcm outputs

determination of the copper isotope composition of seawater revisited a case study from the mediterranean sea abstract a new technique for the determination of dissolved copper isotope composition 65cu of seawater was applied to examine copper sources and internal cycling in the mediterranean sea along the geotraces ga04n transect a succession of chelating resin with nitrilotriacetic acid functional groups and strong base anion exchange resin together with optimization of the multi collector inductively coupled plasma mass spectrometry set up allowed to isolate copper from seawater matrix and to measure the 65cu 63cu ratios in seawater with an external precision of 0 06 2 s d this method was first applied for inter comparison measurements to surface and deep waters sampled at the bermuda atlantic time series station bats in the north atlantic ocean during the geotraces intercalibration cruise 1 disparities in 65cu reported here and in the literature over these samples showed a need to investigate whether a new inter comparison sample should be decided upon or whether the use of uv oxidation can also affect the measurement of 65cu we also measured total dissolved cu concentration dcu t and 65cu for 12 stations in the mediterranean sea the 65cu distribution showed significant variations in the euphotic zone at the chl a maximum and at bottom depths copper isotope ratios ranged from 0 21 to 0 76 0 06 2 s d yielding an average of 0 51 0 20 2 s d n 96 for the mediterranean sea a strong zonation between natural aerosol deposition to the south and anthropogenic aerosol deposition to the north was seen in the sample set dulaquais et al 2017 gerringa et al 2017 rolison et al 2015 natural dust deposits seemed to draw 65cu toward lower values and deeper in the euphotic zone whereas the impact of anthropogenic aerosols seemed restricted to an increase in dcu t at the chl a maximum 65cu showed significant increase which we attributed to scavenging on and or uptake by phytoplankton the isotope signature of cu sources to the mediterranean sea was also investigated and we inferred a significant source of isotopically heavy cu in the gibraltar area potentially originating from a release of cu sulfide leached in the mining area of southern spain i e iberian pyrite belt in rivers and transported to the mediterranean sea in surface by seasonal water mass circulation conversely marine sediments appear to be a source of isotopically light cu to deep waters this study provides new hints on the use of copper isotopes to study sources and sinks of cu in seawater this article is part of a special issue entitled cycles of trace elements and isotopes in the ocean geotraces and beyond edited by tim m conway tristan horner yves plancherel and aridane g gonzalez

widespread freshening in the seasonal ice zone near 140 e off the adelie land coast antarctica from 1994 to 2012 long term water mass changes during 1994 2012 are examined from nine repeat hydrographic sections in the seasonal ice zone along 140 e off antarctica significant freshening trends are detected within most of the water masses from the bottom to surface bottom water freshened by 0 008 0 009 decade 1 below isopycnal surfaces and its layer thickness decreased by 120 160 dbar decade 1 throughout the study period in addition to general thinning the layer thickness was anomalously thin in 2012 suggesting a possible link with the sudden calving of the mertz glacier tongue and subsequent reduction in sea ice production winter water freshened by 0 03 decade 1 throughout the study period with significant interannual variability in the offshore region a long term increase in precipitation can explain a substantial portion of the freshening trend the lower circumpolar deep water on the continental slope underwent freshening at the same rate as the bottom water during the last two decades modified shelf water also shows robust freshening at a rate of 0 03 decade 1 combined with the freshening of near surface and bottom water masses in this region these data indicate freshening of the entire water column over the continental slope this widespread freshening is broadly consistent with the enhancement of the global hydrological cycle together with a possible acceleration of land ice melting key points antarctic bottom water freshened off adelie coast antarctica during 1994 2012 precipitation increase can cause a significant part of winter water freshening the freshening is consistent with the enhancement of global hydrological cycle 2013 american geophysical union all rights reserved

ice sheet mass balance during the last glacial maximum in the framework of the paleoclimate modelling intercomparison project pmip simulations of the last glacial maximum lgm have been performed more than 10 different atmospheric general circulation models agcms have been used with the same boundary conditions sea surface temperatures prescribed by climap 1981 ice sheet reconstruction provided by peltier 1994 change in insolation and reduced co2 content one of the major questions is to investigate whether the simulations of the lgm are in equilibrium with the prescribed ice sheet reconstruction to answer this question we have used two different approaches first we analyze the results of a sel of lgm simulations performed with different versions of the laboratoire de meteorolo gie dynamique lmd agcm and study the hydrologic and snow budgets over the laurcntide and fennoscandian ice sheets second we use the agcm outputs to force an ice sheet model in order to investigate its ability to maintain the ice sheets as reconstructed by climap 1981 or peltier 1994

antarctic sea ice mapping using the avhrr abstract a sea ice mapping scheme based on advanced very high resolution radiometer avhrr data from the national oceanic and atmospheric administration noaa polar orbiting satellites has been developed and applied to daylight images taken between november 1989 to january 1990 and november 1990 to january 1991 over the weddell and the ross seas after masking the continent and ice shelves sea ice is discriminated from clouds and open sea using thresholds applied to the multidimensional space formed by avhrr channel 2 3 and 4 radiances sea ice concentrations in cloud free regions are then computed using the tie point method results based on the analysis of more than 70 images show that the proposed scheme is capable of properly discriminating between sea ice open sea and clouds under most conditions thus allowing high resolution sea ice maps to be produced during the austral summer season

direct observations of the antarctic slope current transport at 113 e the antarctic slope current asc defined here as the region of westward flow along the continental slope off antarctica forms the southern limb of the subpolar gyres it regulates the exchange of water across the shelf break and provides a path for interbasin westward transport despite its significance the asc remains largely unobserved around most of the antarctic continent here we present direct velocity observations from a 17 month current meter moored array deployed across the continental slope between the 1000 and the 4200 m isobaths in the southeastern indian ocean near 113 e the observed time mean flow consists of a surface intensified jet associated with the antarctic slope front asf and a broader bottom intensified westward flow that extends out to approximately the 4000 m isobath and is strongest along the upper slope the time mean transport of the asc is 29 2 sv fluctuations in the transport are large typically exceeding the mean by a factor of 2 they are mainly due to changes in the northward extent of the current over the lower slope however seasonal changes in the wind also drive variations in the transport of the asf and the flow in the upper slope both mean and variability are largely barotropic thus invisible to traditional geostrophic methods this article is protected by copyright all rights reserved

surface winds over the antarctic continent a review surface winds over antarctica often classified as katabatic are intimately related to the orientation and steepness of the underlying ice terrain such flows result primarily from the strong radiational cooling of the sloping ice surface which creates a downslope directed horizontal pressure gradient force it is possible to diagnose the time averaged near surface streamline patterns of cold air drainage currents using recently compiled detailed antarctic ice topography maps and appropriate estimates of the strength of the surface temperature inversion the resulting streamlines agree with available observations and illustrate the high degree of nonuniformity of gravity driven flows off the ice sheets in certain interior sections negatively buoyant air from a large catchment area drains through a restricted section of coastline such confluence zones represent regions of enhanced supplies of cold air and are shown to be related to anomalously strong katabatic winds implications for sea ice formation are discussed

coupling an agcm with an ism to investigate the ice sheets mass balance at the last glacial maximum the aim of this paper is to investigate the consistency between the ice sheets reconstruction at the lgm and the climate simulated by agcm in particular to investigate whether the laurentian and the fennoscandian ice sheets have an equilibrated mass balance we use two complementary approaches first we analyze the changes of snow and water budgets over the ice sheets only using the model results of lgm runs second we use a thermomechanical ice sheet model ritz et al 1997 forced with the agcm simulated climate to perform long term runs at finer spatial resolution analyzing the results obtained with both approaches we show that the ice sheet mass balance computed directly from agcm results may be biaised moreover we show using two versions of the lmd agcm that the ice sheet mass balance computed by the ism is drastically sensitive to the summer surface temperatures simulated by the agcm

the geometry and rates of microplate motions in the eastern mediterranean sea quantitative constraints by using anoxic basins as piercing points abstract anoxic conditions encountered in small basins on the flanks of the mediterranean ridge are due to the formation of brine pools caused by exposure of messinian evaporites seismic reflection profiles and structural data indicate young active strike slip faulting and thrusting due to collision between microplates to be responsible for the continued isolation of the basins an estimate of 100 000 years for the age of initiation of the tyro and kretheus basins using a finite microplate rotation model for the central and eastern mediterranean sea is in close agreement with coring results in the kretheus basin rates of relative motion with respect to africa of more than 8 cm a 1 along the western strabo trench are supported by these results this study indicates that regional deformation resulting from active plate convergence appears to bear a simple relation to a few finite rotation poles for relative movement between plates and microplates

the surface windfield over the antarctic ice sheets the intense radiative cooling of air over the ice slopes of antarctica generates a surface wind regime that is strongly controlled by topography and plays a key role in determining the behaviour of the atmosphere and ocean in high southern latitudes1 7 resultant surface winds are intimately linked to the orientation of the ice terrain fig 1 and display the highest degree of persistence found on earth the close coupling between wind and topography allows estimation of the former if the latter is known with some precision here we report on time averaged near surface airflow over the antarctic continent during winter diagnosed from a recent accurate synthesis of terrain slopes and from estimates of the lower atmospheric temperature structure the simulated drainage pat tern exhibits strong spatial variability with the airflow concentrated into several zones near the coastal margin these confluence regions are responsible for strong persistent katabatic winds over downstream coastal stretches and are indicative of zones of greatest katabatic potential

integrated assessment of the tarut island coast arabian gulf saudi arabia in order to assess pollutants on the tarut island coast saudi arabian gulf 38 coastal sediment samples 40 mollusk specimens and 26 seawater samples were collected for fe cu pb mn cd se as co b cr hg mo and zn analysis using inductively coupled plasma mass spectrometer the analysis indicated that the coastal sediments were enriched polluted and contaminated with as pb cd and hg gastropods were good accumulators for fe cu zn pb mn cd and co while bivalves were good accumulators for se cr and hg the spatial distribution of heavy metals in seawater samples indicated no obvious trend along the studied coast land reclamation dust storms petrochemical industries oil leakage desalination plants and sewage effluents were the significant sources of heavy metal pollutants along tarut coast the comparison between heavy metals in the tarut island coast and other worldwide coasts was emphasized