south polar residual cap of mars features stratigraphy and changes abstract the south residual polar cap of mars rich in co2 ice is compositionally distinct from the north residual cap which is dominantly h2o ice the south cap is also morphologically distinct displaying a bewildering variety of depressions formed in thin layered deposits which have been observed to change by scarp retreat over an interval of one mars year malin et al 2001 science 294 2146 2148 the climatically sensitive locale of the residual caps suggests that their behavior may help in the interpretation of recent fluctuations or repeatability of the mars climate we have used mars global surveyor mars orbiter camera moc images obtained in three southern summers to map the variety of features in the south residual cap and to evaluate changes over two mars years mars y the images show that there are two distinct layered units which were deposited at different times separated by a period of degradation the older unit 10 m thick has layers approximately 2 m thick the younger unit has variable numbers of layers each 1 m thick the older unit is eroding by scarp retreat averaging 3 6 m mars y a rate greater than the retreat of 2 2 m mars y observed for the younger unit the rates of scarp retreat and sizes of the different types of depressions indicate that the history of the residual cap has been short periods of deposition interspersed with longer erosional periods erosion of the older unit probably occupied 100 150 mars y one layer may have been deposited after the mariner 9 observations in 1972 residual cap layers appear to differ from normal annual winter deposits by having a higher albedo and perhaps by having higher porosities these properties might be produced by differences in the depositional meteorology that affect the fraction of high porosity snow included in the winter deposition

th u dating of strombus bubonius bearing marine terraces in southeastern spain single dates obtained on mollusk shells by the u series nuclides method are highly unreliable primarily because of the mobility of uranium isotopes however in several cases a statistical approach was demonstrated to yield coherent chronologies in both continental and marine environments the authors report on 34 new th and u isotope measurements on strombus bubonius and glycymeris glycymeris fossils from raised marine terraces in the almeria area southeastern spain the results yield a coherent chronology that indicates the presence of the warm water s bubonius fauna in the mediterranean basin reconsideration of the tyrrhenian stratigraphy based on the presence of s bubonius is thus required

foredeeps versus subduction zones the geologic characteristics of foredeeps and accretionary wedges suggest that these features are distinguishable on the basis of the direction of the associated subduction east north east dipping subduction related accretionary wedges show high relief and broad outcrops of metamorphic rocks they are associated with shallow foredeeps with low subsidence rates in contrast west dipping subduction related accretionary wedges show low relief and involve mainly sedimentary cover the related foredeeps are deep and have high subsidence rates this differentiation is useful both for oceanic and continental subductions e g eastern vs western pacific subductions or east dipping alpine vs west dipping apenninec subductions in a cross section of the alps the ratio of the area of the orogen to the area of the foredeeps is at least 2 1 whereas this ratio is 0 22 1 for the apennines these ratios explain why foredeeps related to east or northeast dipping subduction are quickly filled and are bypassed by clastic rocks whereas foredeeps related to west dipping subduction maintain a deep water environment longer these differences support the presence of an eastward asthenospheric counterflow relative to the westward drift of the lithosphere detected in the hot spot reference frame even in the mediterranean where no hot spots are present in this interpretation the apennines foredeep was caused by the eastward push of the mantle acting on the subducted slab whereas the foredeeps in the alps were caused by the load of the thrust sheets and the downward component of movement of the upper adriatic plate these forces contrast with the upward component of the eastward mantle flow

an oceanographic nowcast forecast system for the red sea we describe the application of a nowcast forecast system for three dimensional currents temperature and salinity to the red sea the modeling system is constructed around a high resolution 6 7 km primitive equation numerical circulation model with complete thermodynamics and an imbedded turbulence closure submodel it is coupled to near real time databases containing meteorological forecasts and remotely sensed and in situ temperature and salinity data the temperature and salinity data are ingested into the model daily using a nudged objective analysis technique because the red sea is a relatively narrow basin bounded by typically high and complex orography a single layer atmospheric boundary layer submodel has been used to increase the effective resolution of the original 40 km resolution meteorological fields by taking into account orographic steering of the low level winds in order to validate the modeling system two very complete hydrographic surveys of the red sea were undertaken and their results are described both the surveys and the modeling system nowcasts demonstrate that the circulation pattern of the red sea is variable and often composed of a series of eddies or subgyres mainly anticyclones immediately before one survey the winds tended to be along axis while just before the second they tended to be cross axis the red sea circulation was much more eddy like when the winds were cross axis by forcing the modeling system with and without orographically steered winds we were able to establish that the complex eddy structure is a response to a wind field which can be highly structured and vorticity rich because of interaction with the high and variable adjacent orography when the winds are more along axis there is less interaction with the adjacent orography and consequently there are fewer eddies in the red sea

signature of the agulhas current in high resolution satellite derived wind fields abstract 5 years of systematic envisat advanced synthetic aperture radar asar acquisitions and 8 years of observations from the jason 2 altimeter are used to investigate the signature of the agulhas current on high resolution between 1 and 5 km satellite derived winds the satellite wind observations are analysed together with co located ocean current sea surface temperature sst and significant wave height information satellite derived winds cannot be considered current relative over the agulhas current sar and altimeter winds increase in magnitude over the agulhas current in all up down and cross current wind conditions with contributions from both the ocean surface current and sst when winds blow against the current strong accelerations in satellite winds are observed at the agulhas current s inshore front with the strongest winds observed 10 km offshore from the location of maximum sst gradient the strong sst gradient appears to drive a thermal wind with a magnitude of about 1 m s and which intensifies abates the predominant alongfront winds at the agulhas current s northern wall the sar dataset shows abnormally high increases in wind speeds during up current conditions in comparisons to the jason 2 derived winds we argue that these differences are caused by the inability of the cmod type algorithms to taken into account the wave field and provide accurate wind speed estimates in conditions where wave height exceed the expected value for a given wind speed our analysis suggests that wave current interactions in regions of strong current shear produce enhanced sea surface roughness signatures and lead to artificially high estimates of sar derived wind speeds there is future potential in using high resolution sar imagery to map strong ocean current fronts and thus improve our ability to monitor ocean surface currents from space

mesoscale air sea interaction and its role in eddy energy dissipation in the kuroshio extension abstractusing the high resolution community earth system model cesm output this study investigates air sea interaction and its role in eddy energy dissipation in the kuroshio extension ke regi

ionian marine terraces of southern italy insights into the quaternary tectonic evolution of the area 1 new detailed morphotectonic analyses of a well exposed flight of marine terraces along the ionian coast of southern italy has been carried out the area represents a key transect for investigating the middle late quaternary evolution of the southern apennines chain foredeep foreland geodynamic system a major result of the research is the reconstruction of a virtually complete 3d geometry of the marine surfaces along a coastal sector of ca 70 km which 1 documents the occurrence of 18 paleo shorelines and 2 provides evidence for a strong regional uplift affecting the investigated area following a systematic critical review of literature relating to geochronological data integrated with a morphogenetic model based on the interaction between tectonic uplift and eustatic sea level changes the different terraces are correlated to as many highstand sea level peaks dating the highest oldest terrace to ca 600 ka mis 15 the vertical and horizontal distribution of the terraces show a general convergence of the paleo shorelines toward nne which indicates a decreasing trend in differential uplift in that direction ranging from almost 2 mm a in the southwestern sector to about 0 2 mm a in the northeastern sector detailed mapping and 3d reconstruction also emphasize the partitioning of the area into three distinct sectors characterized by different tilting rates this behavior is likely caused by the combined role and activity of three major tectonic structures working at different scales and rates including 1 the reactivation of an out of sequence thrust 2 sliding along the basal detachment of the external apennines wedge and 3 a lithospheric scale duplexing crustal or deeper as a major conclusion within the external sector of the southern apennines chain and its foredeep regional shortening and a contractional tectonic regime persisted throughout the whole quaternary and it is probably still active

spreading of red sea overflow waters in the indian ocean as a result of its remarkably high salinity and despite its small volume input remnants of red sea water rsw have been identified in the agulhas current over 6000 km distant of their source this provided the motivation to investigate the long term mean spreading of rsw throughout the indian ocean using a comprehensive set of observations taken from the national oceanographic data center archives and from the world ocean circulation experiment hydrographic program for the indian ocean after emerging from the gulf of aden into the arabian sea rsw spreads predominantly southwestward along the african continental slope as indicated by strongly inclined isohalines across the arabian sea there is some monsoon variability so that during the winter monsoon there is more rsw present in the gulf of aden and an intensification of southward spreading along the western boundary between 12 and 5 n elsewhere the intermediate depth salinity field of the indian ocean appears relatively stationary between 5 and 10 s in the region of the south equatorial current isohalines of the rsw layer become quasi zonal across the width of the indian ocean only dipping southward toward the western boundary west of 50 e south of here there is a strong tongue of rsw spreading southward through the mozambique channel and into the agulhas current these conclusions concur with previous localized investigations of intermediate water properties using a simple mixing model the percentage of rsw throughout the indian ocean was quantified it was found that the flux of salt into the gulf of aden from the red sea is similar to that estimated to cross 32 s in the agulhas current this result implies that all the rsw which is mixed into the interior of the indian ocean may eventually be exported at the western boundary furthermore it implies that rsw is the dominant component of the salt budget for the intermediate layer and that input from the indonesian seas and via diapycnic processes are small

air sea heat exchange along the northern sea surface temperature front in the eastern tropical pacific abstract the atmospheric response to the oceanic forcing in the eastern pacific along the northern equatorial sea surface temperature sst front is investigated in terms of sensible and latent heat flux during the 6 month period from 28 july 1999 to 27 january 2000 and the 7 month period from 28 june 2000 to 27 january 2001 of particular interest is the atmospheric boundary layer abl response to oceanic tropical instability waves tiws that distort the sst front during may january in normal years in previous studies time series of surface heat fluxes clearly show the influence of tiws but the relationship to spatial patterns of sst and wind speed has been inferred only from sparse in situ data in this study satellite observations are used as a basis for compositing in situ data from moorings to compensate for the lack of a spatially dense mooring array the variability in the position of the sst front caused by westward propagating tiws enables fixed mooring locations to measure the abl response

modes of subsurface intermediate and deep water renewal in the red sea a linear box model of the red sea is presented the model which inverts hydrographic and 3he data for the main features of the width integrated circulation is able to describe a large part of the seasonal and annual mean circulation by combining and reconciling major elements of current theories of the red sea circulation available flow measurements and tracer data the model provides a unified conceptual framework for the understanding of the circulation of the red sea the model forms deep water in the extreme north in two modes as first suggested by cember 1988 the convective mode renews the bottom water at an annual mean rate of 0 04 sv in the winter the isopycnal mode water renews the uppermost part of the deep water mass it flows to the south along the bottom of the pycnocline at an annual mean rate of 0 02 0 04 sv a new feature in the model s near surface circulation scheme is the ventilation of the thermocline in the winter at a mean rate of 0 04 sv also from the extreme north there is also a middepth return flow to the north at an annual mean rate of 0 07 sv this flow has been suggested but never rigorously quantified before

bidecadal sea level modes in the north and south atlantic oceans the relationship between the north and south atlantic bidecadal sea level sl oscillations during the twentieth century is investigated for the first time using simple ocean data assimilation reanalysis complex empirical orthogonal function analysis of the bidecadal band gives two dominant modes the first dominating from 1915 to 1965 and the second from 1970 onward the long term time dependent change of mode dominance suggests a structural type regime shift the first mode is characterized by states with north and south atlantic subtropical gyres in phase while tropical and subpolar regions are in opposite phase relative to them the second mode is characterized by the subpolar gyre and north subtropical gyre almost in quadrature with north and south subtropical gyres out of phase thermal rossby waves are very clear only in the second mode these waves seem to be influenced by bottom topography known atlantic meridional overturning circulation amoc sea level fingerprints and amoc strength indices are discussed in the bidecadal oscillations context

satellite measurements reveal persistent small scale features in ocean winds four year averages of 25 kilometer resolution measurements of near surface wind speed and direction over the global ocean from the quikscat satellite radar scatterometer reveal the existence of surprisingly persistent small scale features in the dynamically and thermodynamically important curl and divergence of the wind stress air sea interaction over sea surface temperature fronts throughout the world ocean is evident in both the curl and divergence fields as are the influences of islands and coastal mountains ocean currents such as the gulf stream generate distinctive patterns in the curl field these previously unresolved features have important implications for oceanographic and air sea interaction research

an oceanic general circulation model ogcm investigation of the red sea circulation 2 three dimensional circulation in the red sea 1 the three dimensional circulation of the red sea is studied using a set of miami isopycnic coordinate ocean model micom simulations the model performance is tested against the few available observations in the basin and shows generally good agreement with the main observed features of the circulation the main findings of this analysis include an intensification of the along axis flow toward the coasts with a transition from western intensified boundary flow in the south to eastern intensified flow in the north and a series of strong seasonal or permanent eddy like features model experiments conducted with different forcing fields wind stress forcing only surface buoyancy forcing only or both forcings combined showed that the circulation produced by the buoyancy forcing is stronger overall and dominates the wind driven part of the circulation the main circulation pattern is related to the seasonal buoyancy flux mostly due to the evaporation which causes the density to increase northward in the basin and produces a northward surface pressure gradient associated with the downward sloping of the sea surface the response of the eastern boundary to the associated mean crossbasin geostrophic current depends on the stratification and b effect in the northern part of the basin this results in an eastward intensification of the northward surface flow associated with the presence of kelvin waves while in the south the traditional westward intensification due to rossby waves takes place the most prominent gyre circulation pattern occurs in the north where a permanent cyclonic gyre is present that is involved in the formation of red sea outflow water rsow beneath the surface boundary currents are similarly intensified southward undercurrents that carry the rsow to the sill to flow out of the basin into the indian ocean index terms 4243 oceanography general marginal and semienclosed seas 4255 oceanography general numerical modeling 4532 oceanography physical general circulation keywords red sea marginal sea oceanic general circulation model water mass formation

sea level change along the french mediterranean coast for the past 30 000 years abstract observational evidence for sea level change along the french mediterranean coast has been examined and compared with glacio hydro isostatic models to predict the spatial and temporal patterns of change for about the past 30 000 14c years these predictions are pertinent to discussions of changing ocean volumes during this interval the tectonic stability or otherwise of the coastal areas mantle rheology and the timing of possible human occupation of the now submerged coastal plain and caves such as cosquer cave near marseille the principal results from the analysis are i sea levels along this section of the coast have risen continually since the time of the last glacial maximum lgm and at no time during the holocene has the mean sea level been higher than that of today ii the coast has been tectonically stable between marseille and nice as well as further to the west in roussillon western corsica may have experienced a slow tectonic uplift of between 0 15 0 3 mm year for the past 3000 years but northernmost corsica appears to have been stable during this same interval iii during the lgm sea levels along the coast and immediate off shore areas stood at between 105 115 m below present level the range reflecting the importance of the isostatic contributions during oxygen isotope stage 3 sea levels do not appear to have risen locally above about 60 m iv the rebound parameters describing the mantle rheology and ice sheets required to match the limited observational evidence are consistent with the results of similar analyses carried out for other parts of europe because of its distance from the former northern ice sheets the isostatic factors are particularly sensitive to the value of the lower mantle viscosity v the model predictions for sea level change at the cosquer cave site and for its immediate environments indicate that the cave was last readily accessible before about 10 700 500 14c years about 12 500 500 cal years bp and that the cave entrance was completely flooded by 9000 200 radiocarbon years bp between about 9800 and 10 300 calibrated years bp the cave was above sea level throughout the oxygen isotope stage 3

ocean atmosphere covariability in the western arabian sea abstract the western arabian sea exhibits strong spatial variability in sea surface temperature sst during the southwest monsoon with changes in sst that can exceed 5 c over 200 km exploration of satellite based and in situ data shows a strong connection between mesoscale sst features and changes in the atmospheric boundary layer the fundamental relationship is that of weak strong wind velocities overlying cold warm sst features there are also coherent changes in other near surface meteorological parameters such as the air sea temperature difference and relative humidity indicating changes in the stability of the planetary boundary layer over the mesoscale sst features these relationships are similar to those recently reported over the equatorial pacific tropical instability wave region this observed covariability of atmospheric boundary layer structure and sst results in variations of the surface heat and moisture fluxes latent heat flux is modified by changes in relative humidity principa

wind wave source functions in opposing seas the red sea is a challenge for wave modeling because of its unique two opposed wave systems forced by opposite winds and converging at its center we investigate the different physical aspects of wave evolution and propagation in the convergence zone the two opposing wave systems have similar amplitude and frequency each driven by the action of its own wind wave patterns at the centre of the red sea as derived from extensive tests and intercomparison between model and measured data suggest that the currently available wave model source functions may not properly represent the evolution of the local fields that appear to be characterized by a less effective wind input and an enhanced white capping we propose and test a possible simple solution to improve the wave model simulation under opposing winds and waves condition this article is protected by copyright all rights reserved

on wind wave current interactions during the shoaling waves experiment 1 this paper presents a case study of wind wave current interaction during the shoaling waves experiment showex surface current fields off duck north carolina were measured by a high frequency ocean surface current radar oscr wind wind stress and directional wave data were obtained from several air sea interaction spar asis buoys moored in the oscr scanning domain at several times during the experiment significant coastal currents entered the experimental area high horizontal shears at the current edge resulted in the waves at the peak of wind sea spectra but not those in the higher frequency equilibrium range being shifted away from the mean wind direction this led to a significant turning of the wind stress vector away from the mean wind direction the interactions presented here have important applications in radar remote sensing and are discussed in the context of recent radar imaging models of the ocean surface

satellite observations of the wind jets off the pacific coast of central america part i case studies and statistical characteristics measurements of near surface winds by the nasa scatterometer nscat from october 1996 through june 1997 are analyzed to investigate the three major wind jets along the pacific coast of central america that blow over the gulfs of tehuantepec papagayo and panama each jet is easily identifiable as locally intense offshore winds in the lee of low elevation gaps through the sierra madre mountain range the jets have relatively narrow cross stream width but often extend several hundred kilometers or more into the pacific the tehuantepec and papagayo jets sometimes merge with the northeast trade winds of the pacific the tehuantepec jet was highly energetic with characteristic timescales of about 2 days events were triggered by high pressures associated with cold surges into the gulf of mexico that originated over the great plains of north america the papagayo and panama jets were much more persistent than the tehuantepec jets the winds at both of these lower latitude locations exhibited a strong seasonal variation with almost exclusively offshore flow from late november 1996 through late may 1997 and periods of onshore flow in october and november during the late stages of the 1996 central american monsoon season superimposed on this low frequency seasonal variation were events with characteristic timescales of a few days based on nscat data the spatial and temporal evolution of major wind events is described in detail for three representative case studies in december 1996 the jets developed sequentially from north to south consistent with the notion that wind events in the two lower latitude jets are associated with cold air outbreaks that trigger the tehuantepec jet a day or so earlier in november 1996 and march 1997 the papagayo and panama jets were strongly influenced by tropical phenomena that had little apparent association with the tehuantepec jet these latter two case studies together with the distinction between the statistical characteristics of the three jets suggest that the papagayo and panama jets are predominantly controlled by a mechanism that is very different from the across gap pressure gradients associated with high pressure systems of midlatitude origin that control the tehuantepec jet

regional model simulations of marine boundary layer clouds over the southeast pacific off south america part ii sensitivity experiments abstract the sensitivity of a regional climate model to physical parameterizations and model resolution is investigated in terms of its simulation of boundary layer stratocumulus scu clouds over the southeast pacific specifically the physical schemes being tested include shallow cumulus convection subgrid vertical mixing cloud droplet number concentration cdnc and drizzle as described in part i the model with standard settings captures the major features of the boundary layer in the region including a well mixed marine boundary layer a capping temperature inversion scu clouds and the boundary layer regime transition from the well mixed layer near the coast of south america to a decoupled cloud layer over warmer water to the west turning off the shallow cumulus parameterization results in a dramatic increase in the simulated scu clouds while the boundary layer structure becomes unrealistic losing the decoupled regime over warm water with reduced penetrative mixing at the top of shallow cu

wind forcing of the coastal circulation off north and northwest iberia comparison of atmospheric models 1 comparisons between observed winds and winds from reanalysis national centers for environmental prediction ncep reanalysis 1 and 2 and forecast meteorological models high resolution limited area model hirlam agencia estatal de meteorologia 0 2 and atmospheric research mesoscale model version 5 meteogalicia with 30 km and 10 km resolution have been performed for the coastal region around northwest and north iberia during a typical autumn downwelling period september december 2002 observations at buoys and coastal stations and quikscat derived winds were employed the analyzed period was dominated by southerly and southwesterly winds associated to the passage of low pressure systems our results show that the westward component is higher on the north coast than on the west coast and that winds are intensified at the western north coast in this situation the performance is similar in all model products in general terms but only hirlam represents the reduction of winds in the cantabrian sea and ncep and mm5 overestimate the magnitude of south southwest winds spatial differences in winds are also obtained for upwelling favorable events associated either with a high pressure system north from iberia at the beginning of the autumn transition northeasterly winds or with conditions after the passage of a low pressure system northwesterly winds the existence of sea surface temperature sst gradients in the coastal region implies that higher resolution boundary sst products for meteorological models are necessary finally the effect of these wind products on the coastal circulation was assessed with a 3 d numerical simulation differences in the expansion confinement of river plumes and the surface speed of the slope current are induced by differences in wind patterns over the shelf and slope area among atmospheric models

soil development on marine terraces near metaponto gulf of taranto southern italy abstract for decades the marine terraces in the metaponto area have been the subject of discussions concerning their number sedimentology genesis and age this paper contributes to landscape history reconstruction from a pedogenetic view the marine terraces are generally covered by loamy sediments which have been interpreted in previous works as lagoonal and or alluvial sediments deposited shortly after the emergence of the land surface above sea level pedogenetic investigation including field observations e g soil colour intensity of weathering precipitation of secondary carbonates and fed fet ratio silt clay ratio and carbonate content reveals that the usual sedimentation history on the terraces includes a period of soil formation between the deposition of the marine and that of the alluvial sediments most likely soil formation began after the relative sea level maximum within the same interglacial during which the marine terrace formed later alluvial sediments accumulated during a time of periodic flooding while soil development in the underlying marine sediments probably continued at reduced rates one central question of this study is whether soil formation indicates progressive ages of the terraces the complex landscape history involving several sedimentation and erosion phases makes the correlation of soil development stages with terrace ages difficult nevertheless maximum fed fet ratios and ca mg k na al ratios of the soils developed in the different sediments plotted vs assumed terrace age indicate increasing soil development the relationship between fed fet ratios and terrace age can be best described by power r2 0 89 or logarithmic functions r2 0 72 both describing a strong increase in pedogenic iron in the first 100 ka which slows down afterwards ca mg k na al ratios follow a logarithmic decrease with time r2 0 99 indicating progressive silicate weathering associated with element release and leaching

westward mountain gap wind jets of the northern red sea as seen by quikscat abstract we analyse ten years of quikscat satellite surface winds to statistically characterize the spatio temporal variability of the westward mountain gap wind jets over the northern red sea these wind jets bring relatively cold and dry air from the arabian desert increasing heat loss and evaporation over the region similar to cold air outbreaks from mid and subpolar latitudes quikscat captures the spatial structure of the wind jets and agrees well with in situ observations from a heavily instrumented mooring in the northern red sea the local linear correlations between quikscat and in situ winds are 0 96 speed and 0 85 direction quikscat also reveals that cross axis winds such as the mountain gap wind jets are a major component of the regional wind variability the cross axis wind pattern appears as the second or third mode in the four vector empirical orthogonal function analyses we performed explaining between 6 to 11 of the wind variance westward wind jets are typical in winter especially in december and january but with strong interannual variability several jets can occur simultaneously and cover a large latitudinal range of the northern red sea which we call large scale westward events quikscat recorded 18 large scale events over ten years with duration between 3 to 8 days and strengths varying from 3 4 to 9 10 m s these events cause large changes in the wind stress curl pattern imposing a remarkable sequence of positive and negative curl along the red sea main axis which might be a wind forcing mechanism for the oceanic mesoscale circulation

organic molecules in the sheepbed mudstone gale crater mars the sample analysis at mars sam instrument on board the mars science laboratory curiosity rover is designed to conduct inorganic and organic chemical analyses of the atmosphere and the surface regolith and rocks to help evaluate the past and present habitability potential of mars at gale crater central to this task is the development of an inventory of any organic molecules present to elucidate processes associated with their origin diagenesis concentration and long term preservation this will guide the future search for biosignatures here we report the definitive identification of chlorobenzene 150 300 parts per billion by weight ppbw and c2 to c4 dichloroalkanes up to 70 ppbw with the sam gas chromatograph mass spectrometer gcms and detection of chlorobenzene in the direct evolved gas analysis ega mode in multiple portions of the fines from the cumberland drill hole in the sheepbed mudstone at yellowknife bay when combined with gcms and ega data from multiple scooped and drilled samples blank runs and supporting laboratory analog studies the elevated levels of chlorobenzene and the dichloroalkanes cannot be solely explained by instrument background sources known to be present in sam we conclude that these chlorinated hydrocarbons are the reaction products of martian chlorine and organic carbon derived from martian sources e g igneous hydrothermal atmospheric or biological or exogenous sources such as meteorites comets or interplanetary dust particles

february 2003 marine atmospheric conditions and the bora over the northern adriatic 1 a winter oceanographic field experiment provided an opportunity to examine the atmospheric marine conditions over the northern adriatic mean february winds are from a northeasterly direction over most of the adriatic and a more northerly direction along the western coast wind speeds are fastest in jets over the ne coast during bora events and weakest in the mid northwestern adriatic diurnal air temperature cycles are smallest on the ne coast and largest in the midwestern adriatic the maximum sea air difference is 10 c on the eastern coast and near zero on the midwestern adriatic boras are northeasterly from wind events that sweep off croatia and slovenia bringing slightly colder and drier air over the northern adriatic the main bora season is december to march winter 2002 2003 was normal for bora events synoptic scale temporal variations are correlated over the northern adriatic fastest bora winds and highest wind stress over the northern adriatic is concentrated in four topographically controlled jets the strongest is the senj jet while the trieste jet extends across the entire northern adriatic between each two jets is a weak wind zone the greatest mean net heat loss is in bora jets in the ne adriatic where it was 438 w m 2 and is weakest in the midwestern northern adriatic where it was near zero wind stress is concentrated over the ne half of adriatic in four bora jets while wind stress is weak in the nw adriatic there is significant variation in wind stress mean and standard deviation structure over the northern adriatic with each bora event

western boundary currents and frontal air sea interaction gulf stream and kuroshio extension abstract in the northern hemisphere midlatitude western boundary current wbc systems there is a complex interaction between dynamics and thermodynamics and between atmosphere and ocean their potential contribution to the climate system motivated major parallel field programs in both the north pacific kuroshio extension system study kess and the north atlantic climate variability and predictability clivar mode water dynamics experiment climode and preliminary observations and analyses from these programs highlight that complexity the gulf stream gs in the north atlantic and the kuroshio extension ke in the north pacific have broad similarities as subtropical gyre wbcs but they also have significant differences which affect the regional air sea exchange processes and their larger scale interactions the 15 yr satellite altimeter data record which provides a rich source of information is combined here with the longer historical record from in situ data to describe and compare the curr

perennial water ice identified in the south polar cap of mars the inventory of water and carbon dioxide reservoirs on mars are important clues for understanding the geological climatic and potentially exobiological evolution of the planet1 from the early mapping observation of the permanent ice caps on the martian poles2 3 the northern cap was believed to be mainly composed of water ice whereas the southern cap was thought to be constituted of carbon dioxide ice however recent missions nasa missions mars global surveyor and odyssey have revealed surface structures4 altimetry profiles5 underlying buried hydrogen6 and temperatures of the south polar regions that are thermodynamically consistent with a mixture of surface water ice and carbon dioxide7 here we present the first direct identification and mapping of both carbon dioxide and water ice in the martian high southern latitudes at a resolution of 2 km during the local summer when the extent of the polar ice is at its minimum we observe that this south polar cap contains perennial water ice in extended areas as a small admixture to carbon dioxide in the bright regions associated with dust without carbon dioxide at the edges of this bright cap and unexpectedly in large areas tens of kilometres away from the bright cap

tower based measurements of normalized radar cross section from lake ontario evidence of wind stress dependence we report here the dependence of the normalized radar cross section nrcs on incidence angle azimuth angle wind speed wind stress and atmospheric stratification for ku band microwave backscatter from a lake the measurements were made in autumn 1987 on lake ontario using a rotating microwave system mounted on a research tower operated by the canada centre for inland waters the results show that at intermediate incidence angles the nrcs on the lake generally increases faster with wind speed than it does on the ocean we attribute this to the larger atmospheric drag coefficients which exist on the lake compared with the ocean and we show that the results are more consistent with a dependence of the nrcs on wind stress than on wind speed near the surface we find a stratification dependence of the nrcs similar to that previously reported at c band and show that at 40 and 60 incidence angles this dependence can be removed by parameterizing the nrcs in terms of either the friction velocity or neutral wind speed at a 20 incidence angle the stratification dependence is not removed by this procedure

a proposal for the kinematic modelling of w dipping subductions possible applications to the tyrrhenian apennines system in w dipping subduction zones there is a general eastward progression of the back arc basin accretionary wedge foredeep complex with the forward progression early stages of the complex are revealed by slices of upper crust and sedimentary cover abandoned to the west left floating above a new section of mantle a major shear zone should form at the new moho separating upper crust slices of earlier accretionary stages and the eastward flowing mantle the mantle wedging at the top of the subduction plane could be responsible for the uplift of the central parts of the belt the retreating of the subduction hinge is interpreted as due to the push generated by the eastward mantle flow detected in the hot spot reference frame the foredeep depth is mainly a function of the radius of curvature of the subduction hinge the frontal wedge is constructed from the stacking of the upper layers of the subducting plate and the syntectonic clastics that fill the foredeep which are progressively involved in thrusting and later by extension in order to preserve volume balance the lithosphere of the eastern plate before subduction has to be the same size as that which has been subducted due to the longer length of the arc with respect to the original length of the linear margin between the two converging plates laterally stretched subducted lithosphere is predicted at depth w dipping subductions usually have a short life probably due to their inherent capability to produce new lateral heterogeneities of the lithosphere the thin back arc which are a key factor in controlling and generating new subductions both e and w dipping this model is applied to the apennines tyrrhenian sea system

validating the nscat winds in the vicinity of the pacific intertropical convergence zone it is known that the nscat winds are influenced by precipitation and so are potentially in error in regions of high rainfall such as the pacific itcz we assess this potential error by comparing nscat winds to other products and by determining the possible impact on modeling the pacific necc in the latitude band of the itcz there are large differences between wind products from the ecmwf and nscat a comparison with tao buoy winds shows a bias of nscat data towards a higher zonal wind stress at 8 n the spatial distribution of this bias distorts the ekman pumping velocity across the itcz and results in a necc that is 0 1 0 2 m s weaker than that forced by the ecmwf winds this is not a trivial amount during the spring when the strength of the necc in the eastern pacific is of the same magnitude

revised crism spectral parameters and summary products based on the currently detected mineral diversity on mars the investigation of hyperspectral data from the mars reconnaissance orbiter compact reconnaissance imaging spectrometer for mars crism and the observatoire pour la mineralogie l eau les glaces et l activitie omega on mars express has revealed an increasingly diverse suite of minerals present on the martian surface a revised set of 60 spectral parameters derived from corrected spectral reflectance at key wavelengths in crism targeted observations and designed to capture the known diversity of surface mineralogy on mars is presented here as summary products some of the summary products have strong heritage to omega spectral parameter calculations this paper also presents newly derived parameters that highlight locations with more recently discovered spectral signatures type locations for the diversity of currently identified mineral spectral signatures have been compiled into a library presented in this work our analysis indicates that the revised set of summary products captures the known spectral diversity of the surface and successfully highlights and differentiates between locations with differing spectral signatures the revised spectral parameter calculations and related products provide a useful tool for scientific interpretation and for future mission landing site selection and operations

warm core ring velocities inferred from nscat the nasa scatterometer nscat was designed to estimate from space the wind velocity relative to the ocean surface velocity assuming that the spatial scale of the meteorological forcing giving rise to the wind is large compared with the diameter of a warm core ring it should be possible to obtain information about the currents in the ring from the demeaned scatterometer winds to test this hypothesis 14 nscat passes obtained within three days of clear avhrr derived sea surface temperature images showing a warm core ring were analyzed for evidence of circulation in the rings the residual wind vectors for the 14 scatterometer passes were binned and averaged by radial distance from ring center the mean azimuthal component of the speed compares well with adcp data collected in one of the rings a maximum of 0 89 m s 50 km from ring center compared with 0 88 m s and 1 0 m s for the two adcp transects both also at 50 km from ring center

ocean currents evident in satellite wind data satellite mounted radar scatterometers designed to quantify surface winds over the ocean actually measure the relative motion between the air and the ocean surface estimates of the wind stress from conventional surface wind measurements are usually derived neglecting ocean currents however when the relative motion is used the differences in the estimated stress can be as large as 50 near the equator and may even reverse sign during an el nino this assertion is supported by the strong relationship between the surface currents measured by the tropical atmosphere ocean tao array in the pacific ocean and the differences between the winds estimated from scatterometer data and those measured by tao anemometers the fact that the scatterometer measures relative motion and not wind alone makes scatterometer derived stress a more accurate representation of the boundary condition needed for both atmospheric and oceanic models than stress fields derived neglecting ocean currents

the polar deposits of mars the tantalizing prospect of a readable record of martian climatic variations has driven decades of work toward deciphering the stratigraphy of the martian polar layered deposits and understanding the role of the residual ice caps that cover them spacecraft over the past decade have provided a massive infusion of new data into mars science polar science has benefited immensely due to the near polar orbits of most of the orbiting missions and the successful landing of the phoenix spacecraft in the northern high latitudes topographic thermal radar hyperspectral and high resolution imaging data are among the datasets that have allowed characterization of the stratigraphy of the polar layered deposits in unprecedented detail additionally change within the residual ice caps has been monitored with spacecraft instruments for several years these new data have provided a golden opportunity to understand the interplay between the martian orbit climate and polar ice

east pacific ocean eddies and their relationship to subseasonal variability in central american wind jets subseasonal variability in sea surface height ssh over the east pacific warm pool off central america is investigated using satellite observations and an eddy resolving ocean general circulation model ssh variability is organized into two southwest tilted bands on the northwest flank of the tehuantepec and papagayo wind jets and collocated with the thermocline troughs eddy like features of wavelength similar to 600 km propagate southwestward along the high variance bands at a speed of 9 13 cm s wind fluctuations are important for eddy formation in the gulf of tehuantepec with a recurring interval of 40 90 days when forced by satellite wind observations the model reproduces the two high variance bands and the phase propagation of the tehuantepec eddies our observational analysis and model simulation suggest the following evolution of the tehuantepec eddies on the subseasonal timescale in response to the gap wind intensification a coastal anticyclonic eddy forms on the northwest flank of the wind jet and strengthens as it propagates offshore in the following two to three weeks an energetics analysis based on the model simulation indicates that besides wind work barotropic and baroclinic instabilities of the mean flow are important for the eddy growth both observational and model results suggest a re intensification of the anticyclonic eddy in response to the subsequent wind jet event off papagayo ocean eddy formation is not well correlated with local wind jet variability in both the gulfs of tehuantepec and papagayo subseasonal ssh variability is preferentially excited on the northwest flank of the wind jet factors for this asymmetry about the wind jet axis as well as the origins of wind jet variability are discussed

upper equatorial pacific ocean current and salinity variability during the 1996 1998 el nino la nina cycle the recent el nino la nina cycle exhibited striking patterns of current and salinity variability in the upper equatorial pacific ocean this evolution is described from mid 1996 through 1998 using a remarkable data set of 35 meridional conductivity temperature depth ctd acoustic doppler current profiler adcp sections along with buoy data the sections nominally from 8 s to 8 n between 165 e and 95 w were occupied over the course of 27 months a wide range of current variability was sampled with currents that appeared or disappeared some time during the cycle including an equatorially trapped eastward surface current the equatorial undercurrent the northern branch of the south equatorial current and the north equatorial countercurrent basin wide interannual changes in upper ocean and pycnocline zonal transports were as large as 64 32 106 m3 s 1 changes in the salinity structure included a deep and fresh mixed layer in the central equatorial pacific that built up during the el nino and was then disrupted by upwelled salty water with the onset of la nina a very fresh mixed layer observed in the eastern equatorial pacific late in the el nino and a reduction in the strength of the meridional equatorial salinity gradient within the pycnocline to one third of the usual value during the el nino finally the zonal transports above the thermocline from 5 s to 5 n were well correlated with the rate of change of warm water volume west of the individual ctd adcp sections

observations of sst induced perturbations of the wind stress field over the southern ocean on seasonal timescales the surface wind stress response to sea surface temperature sst over the latitude range 308 608 si n the southern ocean is described from the national aeronautics and space administration s quikscat scatterometer observations of wind stress and reynolds analyses of sst during the 2 yr period august 1999 to july 2001 while ocean atmosphere coupling at midlatitudes has previously been documented from several case studies this is the first study to quantify this relation over the entire southern ocean the spatial structures of the surface wind perturbations with wavelengths shorter than 108 latitude by 308 longitude are closely related to persistent spatial variations of the sst field on the same scales the wind stress curl and divergence are shown to be linearly related respectively to the crosswind and downwind components of the sst gradient the curl response has a magnitude only about half that of the divergence response this observed coupling is consistent with the hypothesis that sst modification of marine atmospheric boundary layer mabl stability affects vertical turbulent mixing of momentum inducing perturbations in the surface winds the nonequivalence between the responses of the curl and divergence to the crosswind and downwind sst gradients suggests that secondary circulations in the mabl may also play an important role by producing significant perturbations in the surface wind field near sst fronts that are distinct from the vertical turbulent transfer of momentum the importance of the wind stress curl in driving ekman vertical velocity in the open ocean implies that the coupling between winds and sst may have important feedback effects on upper ocean processes near sst fronts

sea state dependent wind work on the oceanic general circulation 1 we examine sea state dependent wind work on the oceanic general circulation using a wave hindcast dataset quikscat winds and geostrophic and total ocean surface currents from 1 aviso and 2 ecco2 model products for wind work on surface geostrophic currents estimated from aviso or ecco2 sea state dependent wind stress increases an average of 24 0 17tw or 23 0 15tw compared with estimates that exclude sea state effects for wind work on the total surface currents the sea state dependent wind stress increases the wind work by about 24 0 4tw in terms of spatial distribution the increase in wind power input occurs mainly in high wind tropical regions and the mid latitude storm track regions like the antarctic circumpolar current region where the relatively rough ocean surface is characterized by young waves and high winds by comparison in some regions with relatively low winds and mature ocean waves there is a slight reduction in estimated wind power input

sst induced surface wind variations over the brazil malvinas confluence satellite and in situ observations abstract the confluence of the brazil malvinas currents maintains strong sea surface temperature sst fronts in the midlatitude southwestern atlantic year round sst effects on near surface stability and surface wind variations are examined in this region using satellite and in situ datasets satellite observations show strong weak surface wind speeds over the warm brazil cold malvinas current a novel feature of this study is the construction of a high resolution surface meteorological dataset that is based on historical ship observations analysis of this new in situ dataset reveals an increased reduced sea air temperature difference over the brazil malvinas current indicating destabilization stabilization in the atmospheric boundary layer these results are consistent with the sst induced vertical mixing mechanism for wind adjustment the sst effect on the near surface atmosphere is observed both in the climatology and on interannual time scales in the brazil malvinas confluence along a zo

somali current rings in the eastern gulf of aden 1 new satellite based observations reveal that westward translating anticyclonic rings are generated as a portion of the somali current accelerates northward through the socotra passage near the mouth of the gulf of aden rings thus formed exhibit azimuthal geostrophic velocities exceeding 50 cm s are comparable in overall diameter to the width of the gulf of aden 250 km and translate westward into the gulf at 5 8 cm s ring generation is most notable in satellite ocean color imagery in november immediately following the transition between southwest boreal summer and northeast winter monsoon regimes the observed rings contain anomalous fluid within their core which reflects their origin in the equator crossing somali current system estimates of socotra passage flow variability derived from satellite altimetry provide evidence for a similar ring generation process in may following the winter to summer monsoon transition cyclonic recirculation eddies are observed to spin up on the eastern flank of newly formed rings with the resulting vortex pair translating westward together recent shipboard and lagrangian observations indicate that vortices of both sign have substantial vertical extent and may dominate the lateral circulation at all depths in the eastern gulf of aden

the age of late pleistocene shorelines and tectonic activity of taranto area southern italy abstract the results of isoleucine epimerization ratios in pelecypods glycymeris sp arca sp and cerastoderma sp and u series dating of bivalves and cladocora caespitosa sampled from different late pleistocene units in the cheradi islands and in the coastal areas of mar piccolo and mar grande near taranto apulia region italy are presented u series measurements on pelecypods and on corals directly associated with mollusc samples provide an independent calibration of amino acid data the d l ratios of isoleucine show a strong correlation with age and thus may be considered as a predictive dating technique this correlation also supports the reliability of u series ages obtained for molluscs these results including the stratigraphic position the lithological lateral continuity the morphological evidence and the palaeontological characteristics of the various units made it possible to attribute them to different marine trangressive phases referable to oxygen isotope stages ois 5e c 5a and 3 no evidence of land emersion between ois 5e and 5c has been found in the area pinkish red sands deposits located above present sea level 1 m have been referred to ois 3 the late pleistocene morphological evolution and uplift of a complex area between the apulian foreland and the bradanic foredeep have been reconstructed due to the lack of incontestable indicators of past sea level stands the facies analysis has been performed on u series dated 89 8 ka ois 5c shoreline north of mar piccolo and an uplift rate ranging from 0 21 0 27 mm yr has been calculated

observational evidence for an active surface reservoir of solid carbon dioxide on mars high resolution images of the south polar residual cap of mars acquired in 1999 and 2001 show changes in the configuration of pits intervening ridges and isolated mounds escarpments have retreated 1 to 3 meters in 1 martian year changes that are an order of magnitude larger than can be explained by the sublimation of water ice but close to what is expected for sublimation of carbon dioxide ice these observations support a 35 year old conjecture that mars has a large surface reservoir of solid carbon dioxide the erosion implies that this reservoir is not in equilibrium with the present environment and that global climate change is occurring on mars

the reliability of uranium series mollusc dates from the western mediterranean basin abstract fossil mollusc shells from western mediterranean raised beach deposits have been dated using u series techniques sub sampling has allowed intra shell isotopic variability to be assessed although most of the calculated ages appear plausible and some internal consistency exists closer scrutiny of the data reveals that the shells have behaved as geochemically open systems and all the ages therefore must be considered suspect some previously published u series mollusc data from the same region may also contain evidence of open system behaviour and are considered equally unreliable simple modelling suggests considerable variation in isotopic uptake behaviour both within and between shells

global ocean surface velocities from drifters mean variance el nino southern oscillation response and seasonal cycle 1 global near surface currents are calculated from satellite tracked drogued drifter velocities on a 0 5 0 5 latitude longitude grid using a new methodology data used at each grid point lie within a centered bin of set area with a shape defined by the variance ellipse of current fluctuations within that bin the time mean current its annual harmonic semiannual harmonic correlation with the southern oscillation index soi spatial gradients and residuals are estimated along with formal error bars for each component the time mean field resolves the major surface current systems of the world the magnitude of the variance reveals enhanced eddy kinetic energy in the western boundary current systems in equatorial regions and along the antarctic circumpolar current as well as three large eddy deserts two in the pacific and one in the atlantic the soi component is largest in the western and central tropical pacific but can also be seen in the indian ocean seasonal variations reveal details such as the gyre scale shifts in the convergence centers of the subtropical gyres and the seasonal evolution of tropical currents and eddies in the western tropical pacific ocean the results of this study are available as a monthly climatology

comment on sea level and climate changes during ois 5e in the western mediterranean by t bardaji j l goy j l c zazo c hillaire marcel c j dabrio a cabero b ghaleb p g silva j lario geomorphology 104 2009 22 37

long term observations of tropical instability waves abstract reynolds sea surface temperature sst data showing tropical instability waves tiws in the tropical pacific are analyzed along with current measurements from the tropical atmosphere ocean tao buoy array and wind speeds from the european remote sensing satellite ers 1 and 2 scatterometers tiws are visible as undulations in the sst cold fronts that delineate the northern and southern boundaries of the cold tongue in the equatorial pacific the sst pattern results from advection of the sst front by instabilities in the near surface equatorial currents although the waves are seen on both sides of the pacific cold tongue and north of the equator in the atlantic they are most intense and thereby most observable in the north equatorial pacific the combination of data used in this analysis provides information about these waves the factors controlling them and their coupling to the atmosphere on annual and interannual timescales on annual timescales the tiws generally establish a strong

late quaternary beach deposits and archaeological relicts on the coasts of cyprus and the possible implications of sea level changes and tectonics on the early populations

spectral reflectance of carbonate minerals in the visible and near infrared 0 35 2 55 microns calcite aragonite and dolomite

zonal surface wind jets across the red sea due to mountain gap forcing along both sides of the red sea 1 mesoscale atmospheric modeling over the red sea validated by in situ meteorological buoy data identifies two types of coastal mountain gap wind jets that frequently blow across the longitudinal axis of the red sea 1 an eastward blowing summer daily wind jet originating from the tokar gap on the sudanese red sea coast and 2 wintertime westward blowing wind jet bands along the northwestern saudi arabian coast which occur every 10 20 days and can last for several days when occurring both wind jets can attain wind speeds over 15 m s 1 and contribute significantly to monthly mean surface wind stress especially in the cross axis components which could be of importance to ocean eddy formation in the red sea the wintertime wind jets can cause significant evaporation and ocean heat loss along the northeastern red sea coast and may potentially drive deep convection in that region an initial characterization of these wind jets is presented

the effects of gap wind induced vorticity the monsoon trough and the itcz on east pacific tropical cyclogenesis abstracttropical cyclogenesis in the eastern north pacific epac basin is related to gap wind induced surface relative vorticity the monsoon trough and the intertropical convergence zone itcz there are several gaps in the central american mountains on the eastern edge of the epac basin through which wind can be funneled to generate surface wind jets gap winds this study focuses on gap winds that occur over the gulf of papagayo and gulf of tehuantepec quick scatterometer quikscat 10 m equivalent neutral winds are used to identify gap wind events that occur during may through november of 2002 08 dvorak fix locations gridded satellite gridsat infrared ir data and national hurricane center nhc tropical cyclone tc reports are used to track the disturbances during the study period surface vorticity is tracked using the quikscat winds and the contribution of surface vorticity from the gap winds to the development of each disturbance is categorized as small medium or large cross calib

residual south polar cap of mars stratigraphy history and implications of recent changes abstract the residual south polar cap rspc of mars includes a group of different depositional units of co 2 ice undergoing a variety of erosional processes complete summer coverage of the rspc by 6 m pixel data of the context imager ctx on mars reconnaissance orbiter mro has allowed mapping and inventory of the units in the rspc unit maps and estimated thicknesses indicate the total volume of the rspc is currently 3 and represents less than 3 of the total mass of the current mars atmosphere scarp retreat rates in the co 2 ice derived from comparison of high resolution imaging science experiment hirise data with earlier images are comparable to those obtained for periods up to 3 mars years earlier these rates combined with sizes of depressions suggest that the oldest materials were deposited more than 125 mars years ago most current erosion is by backwasting of scarps 1 12 m in height this backwasting is initiated by a series of scarp parallel fractures in the older thicker unit these fractures form about every mars year in thinner younger materials they form less frequently some areas of the older thicker unit are lost by downwasting rather than by the scarp retreat a surprising finding from the hirise data is the scarcity of visible layering of rspc materials a result quite distinct from previous interpretations of layers in lower resolution images layers 0 1 m thick are exposed on the upper surfaces of some areas but their timescale of deposition is not known late summer albedo changes mapped by the ctx images indicate local recycling of ice although the amounts may be morphologically insignificant compact reconnaissance imaging spectrometer for mars crism data show that the primary material of all the different forms of the rspc is co 2 ice with only small admixtures of water ice and dust

exposed water ice discovered near the south pole of mars the mars odyssey thermal emission imaging system themis has discovered water ice exposed near the edge of mars southern perennial polar cap the surface h2o ice was first observed by themis as a region that was cooler than expected for dry soil at that latitude during the summer season diurnal and seasonal temperature trends derived from mars global surveyor thermal emission spectrometer observations indicate that there is h2o ice at the surface viking observations and the few other relevant themis observations indicate that surface h2o ice may be widespread around and under the perennial co2 cap

the effects of sst induced surface wind speed and direction gradients on midlatitude surface vorticity and divergence abstract the effects of surface wind speed and direction gradients on midlatitude surface vorticity and divergence fields associated with mesoscale sea surface temperature sst variability having spatial scales of 100 1000 km are investigated using vector wind observations from the seawinds scatterometer on the quick scatterometer quikscat satellite and sst from the advanced microwave scanning radiometer for earth observing system amsr e aqua satellite the wind sst coupling is analyzed over the period june 2002 august 2008 corresponding to the first 6 years of the amsr e mission previous studies have shown that strong wind speed gradients develop in response to persistent mesoscale sst features associated with the kuroshio extension gulf stream south atlantic and agulhas return current regions midlatitude sst fronts also significantly modify surface wind direction the surface wind speed and direction responses to typical sst differences of about 2 4 c are on average about 1 2 m s 1 and 4

the red sea a natural laboratory for wind and wave modeling abstractthe red sea is a narrow elongated basin that is more than 2000 km long this deceivingly simple structure offers very interesting challenges for wind and wave modeling not easily if ever found elsewhere using standard meteorological products and local wind and wave models this study explores how well the general and unusual wind and wave patterns of the red sea could be reproduced the authors obtain the best results using two rather opposite approaches the high resolution weather research forecasting wrf local model and the slightly enhanced surface winds from the global european centre for medium range weather forecasts model the reasons why these two approaches produce the best results and the implications on wave modeling in the red sea are discussed the unusual wind and wave patterns in the red sea suggest that the currently available wave model source functions may not properly represent the evolution of local fields however within limits the wavewatch iii wave model based on

measurements of turbulent vertical kinetic energy in the ocean mixed layer from lagrangian floats d asaro in previous work using nearly neutrally buoyant lagrangian floats in a wind forced mixed layer found w2 5 where w2 is the mean square vertical velocity and u is the friction velocity estimated 2 au from shipboard meteorological measurements using bulk formulas depth profiles of a z 5 w 2 z within 2 u the mixed layer showed a maximum value of a z of about 2 which is 1 75 2 times that measured in solidwall turbulent boundary layers driven by a wall stress alone this result implied that the ocean mixed layer was more energetic than shear driven turbulent boundary layers driven by the same stress here these results are verified using observations of vertical velocity in the mixed layer from 72 float days of data from two lagrangian floats in the north pacific ocean in the autumn of 2000 these floats were more neutrally buoyant than those used previously by d asaro thus reducing possible biases wind stress was estimated from quick scatterometer satellite measurements and is thus subject to errors and biases different from those in d asaro s previous work despite these instrumental differences the new results are very similar to those of the previous work except that no corrections for internal wave velocities are needed the values of w 2

statistical distribution of wave induced drift for random ocean waves in finite water depth abstract based on the linear random wave solutions of water wave equations in finite water depth a theoretical statistical distribution of the wave induced drift is derived the parameters involved in the distribution can be determined by the water depth and the wave spectrum of ocean waves as an illustrative example we consider a simple wind generated sea and the parameters are calculated for typical wind speeds and water depths by using phillips spectrum the behaviours of the distribution and the effects of wind speed and water depth on the distribution are investigated

mariner 9 observations of the south polar cap of mars evidence for residual co2 frost the first spacecraft observations of the south residual polar cap of mars were obtained by the mariner 9 orbiter during the martian southern summer season 1971 1972 analyses of viking orbiter observations obtained 3 mars years later have shown that residual carbon dioxide frost was present at the south polar cap in 1977 in this study mariner 9 infrared interferometer spectrometer spectra and television camera images are used in conjunction with multispectral thermal emission models to constrain the temperatures of dark bare ground and bright frost regions within the south residual cap the results provide strong evidence that carbon dioxide frost was present throughout the summer season despite the fact that the residual frost deposits observed by mariner 9 were less extensive than those observed by viking

comment on the age of late pleistocene shorelines and tectonic activity of taranto area southern italy by g bellouomini m caldara c casini m cerasoli l manfra g mastrronuzzi g palmentola p sanso p tuccimei and p l vesica 6quaternary science reviews 21 525 5479 1

the role of back pressure in the atmospheric response to surface stress induced by the kuroshio abstractthe effect of ocean current drag on the atmosphere is of interest as a test case for the role of back pressure because the response is independent of the thermally induced modulation of the boundary layer stability and hydrostatic pressure the authors use a regional atmospheric model to investigate the impact of drag induced by the kuroshio in the east china sea on the overlying winter atmosphere ocean currents dominate the wind stress curl compared to the impacts of sea surface temperature sst fronts wind stress convergences and divergences are weakly enhanced even though the ocean current is almost geostrophic these modifications change the linear relationships coupling coefficients between the wind stress curl divergence and the sst laplacian crosswind and downwind gradients clear signatures of the ocean current impacts are found beyond the sea surface sea surface pressure back pressure decreases near the current axis and precipitation increases over the downwind region however

spectral evidence for hydrated salts in recurring slope lineae on mars transient streaks that appear seasonally on martian slopes are consistent with brine flows but evidence of water or salts has been lacking analysis of spectral data reveals hydrated salts associated with the streaks confirming a briny origin

seasonality of the kuroshio path destabilization phenomenon in the okinawa trough a numerical study of its mechanism abstract previous observations have indicated that the kuroshio s path in the northern okinawa trough of the east china sea is destabilized and accompanied by meanders with periods of 1 3 months during the winter spring period the present study investigates the mechanism responsible for this recurrent seasonally fixed phenomenon a hypothetical mechanism is constructed based on both a simple wind driven ekman pumping model acting within the kuroshio and a bifurcation model of the kuroshio path states in the northern okinawa trough established in the previous study a high resolution ocean general circulation model is used to examine the hypothetical mechanism the numerical model reveals the following mechanism the wintertime northerly wind prevailing over the okinawa trough blows against the kuroshio generating ekman divergence and hence upwelling within the inshore side of the kuroshio from the sum of the earth s rotation and the geostrophic current shear a necessary condition for this upwelling

extended wind stress analyses for enso abstract surface wind stresses are fundamental to understanding el nino yet most observational stress products are too short to permit multidecadal enso studies two exceptions are the florida state university subjective analysis fsu1 and the ncep ncar reanalysis ncep1 which are widely used in climate research here the focus is on the aspects of the stress most relevant to enso namely the climatological background anomaly spectrum response to sst changes subannual noise forcing and seasonal phase locking and how these differ between fsu1 and ncep1 over the tropical pacific for 1961 99 the ncep1 stress climatology is distinguished from fsu1 by weaker equatorial easterlies stronger off equatorial cyclonic curl stronger southerlies along the peruvian coast and weaker convergence zones with weaker seasonality compared to fsu1 the ncep1 zonal stress anomalies x are weaker less noisy and show less persistent westerly peaks during el nino events ncep1 also shows a more stationary spec

interglacial sea levels abstract isotopic curves have been used as approximative estimators of global sea level calculations of the amplitude of sea level variations during interglacials especially for the last interglacial are based on the study of emerged coral terraces the application of different dating methods shows great uncertainty about the length of each interglacial and also about the number chronology and altitude of the different highstands that occur during each interglacial data of raised marine terraces from areas with different geodynamic behaviour bermudas bahamas peru chile italy and spain are summarized in order to analyze the relationships between sea level and interglacial stages two interglacials have been identified for the early pleistocene represented by two marine terraces with different highstands during the early middle pleistocene an interglacial with several highstands is recorded in uplifted areas during isotopic stage 11 at least one highstand with sea level equal or higher than present has been recorded similar sea level behaviour can be suggested for isotopic stage 9 all the analyzed areas record two highstands during isotopic stage 7 when warm equatorial fauna migrate into the mediterranean during isotopic substage 5e at least two highstands took place with evidence of lowstands between them and at least one highstand during substage 5c with similar sea level height above present msl except in barbados and bermuda during substage 5a at least one highstand has been recorded

characterization of artifacts introduced by the empirical volcano scan atmospheric correction commonly applied to crism and omega near infrared spectra abstract the empirical volcano scan atmospheric correction is widely applied to martian near infrared crism and omega spectra between 1000 and 2600 nm to remove prominent atmospheric gas absorptions with minimal computational investment this correction method employs division by a scaled empirically derived atmospheric transmission spectrum that is generated from observations of the martian surface in which different path lengths through the atmosphere were measured and transmission calculated using the beer lambert law identifying and characterizing both artifacts and residual atmospheric features left by the volcano scan correction is important for robust interpretation of crism and omega volcano scan corrected spectra in order to identify and determine the cause of spectral artifacts introduced by the volcano scan correction we simulated this correction using a multiple scattering radiative transfer algorithm disort simulated transmission spectra that are similar to actual crism and omega derived transmission spectra were generated from modeled olympus mons base and summit spectra results from the simulations were used to investigate the validity of assumptions inherent in the volcano scan correction and to identify artifacts introduced by this method of atmospheric correction we found that the most prominent artifact a bowl shaped feature centered near 2000 nm is caused by the inaccurate assumption that absorption coefficients of co2 in the martian atmosphere are independent of column density in addition spectral albedo and slope are modified by atmospheric aerosols residual atmospheric contributions that are caused by variable amounts of dust aerosols ice aerosols and water vapor are characterized by the analysis of crism volcano scan corrected spectra from the same location acquired at different times under variable atmospheric conditions

high resolution satellite measurements of the atmospheric boundary layer response to sst variations along the agulhas return current abstract the marine atmospheric boundary layer mabl response to sea surface temperature sst perturbations with wavelengths shorter than 30 longitude by 10 latitude along the agulhas return current arc is described from the first year of sst and cloud liquid water clw measurements from the advanced microwave scanning radiometer amsr on the earth observing system eos aqua satellite and surface wind stress measurements from the quikscat scatterometer amsr measurements of sst at a resolution of 58 km considerably improves upon a previous analysis that used the reynolds sst analyses which underestimate the short scale sst gradient magnitude over the arc region by more than a factor of 5 the amsr sst data thus provide the first quantitatively accurate depiction of the sst induced mabl response along the arc warm cold sst perturbations produce positive negative wind stress magnitude perturbations leading to short scale perturbations in the wind stress curl and divergence fields that are li

a search for polycyclic aromatic hydrocarbons over the martian south polar residual cap abstract we present our research on compositional mapping of the martian south polar residual cap sprc especially the detection of organic signatures within the dust content of the ice based on hyperspectral data analysis the sprc is the main region of interest for this investigation because of the unique co 2 ice sublimation features that cover the surface these flat floored circular depressions are highly dynamic and we infer frequently expose dust particles previously trapped within the ice during the wintertime here we identify suitable regions for potential dust exposure on the sprc and utilise data from the compact reconnaissance imaging spectrometer for mars crism on board nasa s mars reconnaissance orbiter mro satellite to examine infrared spectra of dark regions assumed to be composed mainly of dust particles to establish their mineral composition to eliminate the effects of ices on sub pixel dusty features and to look for signatures indicative of polycyclic aromatic hydrocarbons pahs spectral mapping has identified compositional differences between depression rims and the majority of the sprc and crism spectra have been corrected to minimise the influence of co 2 ice whilst no conclusive evidence for pahs has been found within the detectability limits of the crism instrument depression rims are shown to have higher water content than regions of featureless ice and there are possible indications of magnesium carbonate within the dark dusty regions

linear wind forced beta plumes with application to the hawaiian lee countercurrent abstracttwo numerical ocean models are used to study the baroclinic response to forcing by localized wind stress curl i e a wind forced plume which is a circulation cell developing to the west of the source region and composed of a set of zonal jets with implications for the hawaiian lee countercurrent hlcc an idealized primitive equation model regional ocean modeling system roms and a global eddy resolving general circulation model ocean general circulation model for the earth simulator ofes in addition theoretical ideas inferred from a linear continuously stratified model are used to interpret results in roms vertical mixing preferentially damps higher order vertical modes the damping thickens the plume to the west of the forcing region weakening the near surface zonal jets and generating deeper zonal currents the zonal damping scale increases monotonically with the meridional forcing scale indicating a dominant role of vertical viscosity over diffusion a consequence of the

scatterometer winds explain damped rossby waves 1 westward propagating waves in the north pacific ocean from 10 16 n are overwhelmed by a zonally coherent response at the annual period as observed in sea surface height ssh anomalies from the topex poseidon altimeter ssh from a simple model of wind forced rossby waves and from seasonal heating are compared with observed ssh to understand the processes responsible for the observed signal the seasonal heating cycle is out of phase and too weak to explain the ssh the oceanic response to wind stress curl forcing more closely resembles the observations but the response to ncep reanalysis winds does not show a strong annual cycle wind stress curl from the quikscat seawinds scatterometer has a strong and zonally coherent annual cycle that produces a corresonding strong annual signal in ssh the model forced by scatterometer winds demonstrates that the response to ekman pumping is the source of the strong annual cycle in the ssh

last interglacial coastal environments in the mediterranean saharan transition zone abstract the coast of tunisia stretches from the western mediterranean climate belt in the north to the saharan desert climate belt in the south the sediments of this coastal strip provide a record of sea level change if an accurate chronology of the coastal deposits is available we have here surveyed and analysed coastal sites and established a chronology based on optical dating techniques the optical ages range from 156 ka to 62 ka 2 level and cluster around the last interglacial period 125 75 ka our study shows that sea level rose after termination ii for about 25 ka leading to a transgressive deposit at 120 ka a disconformity shown by some deposits suggests a brief drop of sea level during this transgressional phase subsequently for around 40 ka the coastal area became covered by soils colluvia and aeolian sediments indicating a slowly falling sea level while the composition of sediments at the north coast did not change the deposits at the central and south coast experienced a drastic change from a quartz to a carbonate dominated sedimentation sometime during the last interglacial littoral sedimentation ceased at 70 ka when the coast became sediment starved in the course of the falling sea level

the impact of ocean surface currents on sverdrup transport in the midlatitude north pacific via the wind stress formulation abstracta more complete wind stress n formulation takes into account the ocean surface currents vo while the conventional wind stress c popularly used in ocean circulation models is only a function of 10 m winds v10 an analytical solution is derived for the difference of sverdrup transport induced by using n instead of c a scaling analysis of the analytical solution indicates a 6 reduction of the sverdrup transport in the north pacific i e the kuroshio transport in the east china sea when ekman velocity dominates the ocean surface currents because of the quadratic nature of wind stress four nonlinear terms contribute equally to this difference two vorticity torque terms and two speed gradient torque terms a pair of 12 5 yr july 2002 14 hybrid coordinate ocean model simulations that only differ in the wind stress formulation are used to test the analytical solution the model results 2004 14 confirm that using n instead of c reduces the sverdrup transport in the north pacific by 8 17

coastal response to climate change mediterranean shorelines during the last interglacial mis 5 abstract the response of shorelines to climate change is controlled by fall and rise of the sea level and by the alteration of the coastal environment due to changing fluvial discharge and biological activity in the mediterranean this response is complicated by the geographic proximity of the north atlantic and the african monsoon climate systems by a time and space specific interaction of eustatic and water load components of sea level and by the mid latitudinal time lag between orbital forcing and terrestrial response here six mediterranean coastal records are presented which contribute to our understanding of how mid latitudinal coasts respond to orbital forcing the sediment sequences show sharp switches between siliciclastic and carbonate dominated nearshore environments where carbonate rich sediments are composed of oolitic grainstones from modern analogues it is deduced that the oolitic sediments represent a period of relatively high annual sea surface temperature and lack of fluvial discharge the warm arid period was recorded at 114 ka on the southeast iberian coast at 113 ka on the levant coast at 110 ka on the coast west of the nile delta and at 83 ka on the north saharan coast it lasted 10 20 ka in east levant coast and west iberian coast and lasted 40 ka or more in the central south of the east mediterranean timing and duration of the coastal proxy allow inferring instantaneous and dominant response to external forcing in the east and west and delayed and prolonged response due to dominant regional forcing in the centre of the east mediterranean a 9 m eustatic sea level highstand during mis 5e is suggested with a start of the subsequent sea level fall at 118 ka while evidence for multiple mis 5e highstand and a highstand during mis 5a remain elusive

morphometric analysis and amino acid geochronology of uplifted shorelines in a tectonic region near reggio calambria south italy the tectonic coastline of the calabrian peninsula provides an opportunity to study the morphology and history of elevated marine shorelines near capo dell armi eleven shorelines are preserved between sea level and 256 m with some correlation difficulties posed by the dissection of the area by intermittent streams we are able to correlate several of the shorelines across the entire study area with the support of correlations provided by amino acid geochronology we have identified four shorelines dating from the last interglacial period isotope stage 5 the oldest two both contain the strombus bubonius fauna and are of indistinguishable early last interglacial ages stage 5e aminozone e ca 125 ka the highest terrace vii is associated with a shoreline at 157 m and the lower with a shoreline around 125 105 m a s l of the two younger stage 5 without strombus bubonius the higher v lies at about 90 100 m and produces amino acid ratios slightly younger than but statistically indistinguishable from those of aminozone e however the youngest last interglacial shoreline deposits iv have produced amino acid ratios correlated to late stage 5 5a elsewhere in the mediterranean basin amino acid and geomorphic data have shown that uplift varies the study area from 0 85 to 1 03 m ka and suggeststhat constant uplift along any one traverse is unlikely

moored surface wind observations at four sites along the pacific equator between 140 and 95 w abstract mooted surface wind measurements were recorded along the pacific equator at 140 124 110 and 95 w during portions of 1980 85 minimum record length is one year the annual mean and monthly mean westward speeds at 110 w were about 1 5 m s 1 higher during the year preceding the 1982 83 el nino than in the year following this event the annual cycle which moved westward at 0 8 m s 1 consisted of weak westward and northward speeds in february april and vice versa in september october the spectral slope between 5 day and 0 05 day periods was 1 5 the rms amplitude of the 95 statistically significant diurnal period oscillation was 0 3 m s 1 and the meridional component was nearly twice as large as the zonal component the diurnal period wave was coherent at the 95 confidence level between 95 and 124 w with westward phase propagation of about 138 m s 1 no statistically significant at the 95 confidence level spectral peak was found in the 40 to 50 day intraseasonal period band the s