mars odyssey neutron data 1 data processing and models of water equivalent hydrogen distribution 1 for more than 7 years the los alamos built mars odyssey neutron spectrometer mons has measured the neutron albedo from mars in three consecutive energy bands thermal epithermal and fast neutron ranges this paper synthesizes the teamwork on the optimization of the signal extraction the corrections for observational biases and instrument specific characteristics results are presented for neutron time series with an emphasis on seasonal variations at the poles frost free data are mapped on to the surface and the apparent random nature of the counting rate distribution per pixel is analyzed for epithermal neutrons the relative standard deviation is less than 0 5 equatorward of 45 and up to 2 5 above this latitude limit for thermal neutrons it is 1 and 2 5 respectively and for fast neutrons it is 3 and 5 5 respectively new science results are obtained with regards to the distribution of water equivalent hydrogen weh on mars under the assumption of a single uniform distribution of hydrogen with depth weh abundances range from 2 near the equator to 80 at the poles with 2 to 4 5 relative error bars a best approximation to a two layered global distribution of a lower level hydrogen rich substrate beneath an upper layer of varying thicknesses is generated using an average hydration level of an upper layer of 2 wt derived in the paper by feldman et al 2011 such results are discussed and compared with regard to previous publications on the mons instrument

volcanic risk and tourism in southern iceland implications for hazard risk and emergency response education and training abstract this paper examines the relationship between volcanic risk and the tourism sector in southern iceland and the complex challenge emergency management officials face in developing effective volcanic risk mitigation strategies an early warning system and emergency response procedures were developed for communities surrounding katla the volcano underlying the m rdalsjokull ice cap however prior to and during the 2007 tourist season these mitigation efforts were not effectively communicated to stakeholders located in the tourist destination of orsmork despite its location within the hazard zone of katla the hazard zone represents the potential extent of a catastrophic jokulhlaup glacial outburst flood furthermore volcanic risk mitigation efforts in orsmork were based solely on information derived from physical investigations of volcanic hazards they did not consider the human dimension of risk in order to address this gap and provide support to current risk mitigation efforts questionnaire surveys were used to investigate tourists and tourism employees hazard knowledge risk perception adoption of personal preparedness measures predicted behaviour if faced with a katla eruption and views on education results indicate that tourists lack hazard knowledge and they do not adopt preparedness measures to deal with the consequences of an eruption despite a high level of risk perception tourism employees lack knowledge about the early warning system and emergency response procedures results show that tourists are positive about receiving information concerning katla and its hazards and therefore the reticence of tourism employees with respect to disseminating hazard information is unjustified in order to improve the tourism sector s collective capacity to positively respond during a future eruption recommendations are made to ensure adequate dissemination of hazard risk and emergency response information most importantly education campaigns should focus on a increasing tourists knowledge of katla jokulhlaup and other volcanic hazards and b increasing tourist and employee awareness of the early warning and information system and appropriate behavioural response if a warning is issued further tourism employees should be required to participate in emergency training and evacuation exercises annually these efforts are timely given that katla is expected to erupt in the near future and international tourism is an expanding industry in orsmork

coastal upwelling and downwelling forcing of circulation in a semi enclosed bay ria de vigo semi enclosed bays in upwelling regions are exposed to forcing related to winds currents and buoyancy over the shelf the influence of this external forcing is moderated by factors such as connectivity to the open ocean shelter by surrounding topography dimensions of the bay and freshwater outflows such bays preferred locations for ports mariculture marine industry recreational activities and coastal settlement present a range of characteristics understanding of which is necessary to their rational management observations in such a semi enclosed bay the ria de vigo in spain are used to characterize the influence of upwelling and downwelling pulses on its circulation in this location near the northern limit of the iberian upwelling system upwelling events dominate during a short summer season and downwelling events the rest of the year the ria response to the external forcing is central to nutrient supply and resultant plankton productivity that supports its high level of cultured mussel production intensive field studies in september 2006 and june 2007 captured a downwelling event and an upwelling event respectively data from eight current profiler moorings and boat based minibat adcp surveys provided an unprecedented quasi synoptic view of the distribution of water masses and circulation patterns in any ria in the outer ria circulation was dominated by the introduction of wind driven alongshore flow from the external continental shelf through the ria entrances and its interaction with the topography in the middle ria circulation was primarily related to the upwelling downwelling cycle with a cool salty and dense lower layer penetrating to the inner ria during upwelling over the shelf a warmer lower salinity and less dense surface layer of coastal waters flowed inward during downwelling without external forcing the inner ria responded primarily to tides and buoyancy changes related to land runoff under both upwelling and downwelling conditions the flushing of the ria involved shelf responses to wind pulses their persistence for a few days was sufficient to allow waters from the continental shelf to penetrate the innermost ria longer term observations supported by numerical modeling are required to confirm the generality of such flushing events in the ria and determine their typical frequency while comparative studies should explore how these scenarios fit into the range of conditions experienced in other semi enclosed bays

north to south asymmetries in the water equivalent hydrogen distribution at high latitudes on mars 1 water content and burial depths derived from thermal and epithermal neutron currents measured by the mars odyssey neutron spectrometer are used to determine north to south asymmetries and intercorrelations at high latitudes on mars our goal is to contrast observed asymmetries with predictions based on current climate conditions and potential regolith thermophysical and chemophysical properties the average mass fraction of water equivalent hydrogen within the buried layer is higher on average in the south between 60 and 75 latitude and is strongly anticorrelated with burial depth in both hemispheres these results argue that the observed water content at high latitudes may require differing north to south thermophysical and or chemophysical properties of the regolith

a simple model of fjord and coastal circulation interaction abstract the dynamical interaction of a narrow fjord with a wind driven coastal regime is investigated using a linear two layer numerical model the coriolis acceleration is important in the coastal regime but assumed to he unimportant in the fjord dynamical because v 0 for a wide variety of wind conditions bottom topography and model parameters the wind forced coastal circulation with its geostrophic alongshore currants has a strong effect on the circulation within the fjord these geostrophic currents control the free surface and pycnocline displacement at the fjord mouth thereby strongly affecting fjord circulation this mechanism is an alternative to the classical idea of hydraulic control at the mouth by sills or constrictions model simulators also show that the free surface slope is a baroclinic effect and that alongshore and across shore winds affect the fjord differently alongshore winds produce flooding while up and down fjord winds simply sat up the surface we find that offshore win

dynamics of ice ages on mars mars experiences much greater fluctuations in exposure to sunlight than the earth does because of larger variations in astronomical factors such as the tilt of its axis relative to the orbital plane climate change is accordingly more intense on mars than on earth norbert schorghofer has now developed a climate model that accounts for the advance and retreat of the subsurface martian ice sheets over forty major ice ages and five million years this explains the present distribution of subsurface ice on mars in addition lessons learned from the long and relatively simple martian ice age stratigraphy should help when it comes to interpreting the more complicated events here on earth numerical simulation and modelling of the retreat and growth of ground ice on mars demonstrates how the subsurface ice sheets could have evolved and ended up in the state we see them today and also reveals that 40 major ice ages occurred on mars over the past 5 million years unlike earth where astronomical climate forcing is comparatively small mars experiences dramatic changes in incident sunlight that are capable of redistributing ice on a global scale1 2 3 4 5 6 the geographic extent of the subsurface ice found poleward of approximately 60 latitude on both hemispheres of mars7 8 9 coincides with the areas where ice is stable7 10 11 however the tilt of mars rotation axis obliquity changed considerably in the past several million years earlier work3 12 has shown that regions of ice stability which are defined by temperature and atmospheric humidity differed in the recent past from today s and subsurface ice is expected to retreat quickly when unstable11 12 13 here i explain how the subsurface ice sheets could have evolved to the state in which we see them today simulations of the retreat and growth of ground ice as a result of sublimation loss and recharge reveal forty major ice ages over the past five million years today this gives rise to pore ice at mid latitudes and a three layered depth distribution in the high latitudes of from top to bottom a dry layer pore ice and a massive ice sheet combined these layers provide enough ice to be compatible with existing neutron and gamma ray measurements7 8 9

modulation of the semidiurnal cycle of turbulent dissipation by wind driven upwelling in a coastal embayment with two 25 hour series of turbulent microstructure and currents observations carried out in august 2013 during spring chaos 1 and neap tides chaos 2 we investigated the semidiurnal cycle of turbulent dissipation in an embayment affected by coastal upwelling ria de vigo nw iberia at the time of sampling the bay hosted a net wind driven bi directional positive exchange flow and thermal stratification turbulent kinetic energy tke dissipation e at the interface between upwelled and surface waters was enhanced by two orders of magnitude during the ebbs 10 6 w kg 1 with respect to the floods 10 8 w kg 1 this pattern was caused by the constructive interference of the shear associated with the upwelling and tidal currents the vertical structure of the tidal currents was consistent with a deformation of tidal ellipses by stratification which was tightly coupled to the intensity of upwelling this two pronged interaction resulted in a modulation of the semidiurnal cycle of turbulent dissipation by coastal upwelling thus as a result of the upwelling relaxation conditions experienced during chaos 1 depth integrated interior tke dissipation rates were higher by a factor of 2 compared to chaos 2 by using a simple model we determined that observed variations in turbulent mixing had a limited influence on the tidal variations of stratification which were dominated by straining and advection the mixing mechanism described here is potentially relevant for the ecology of upwelling bays as it can stimulate the transport of nutrients from deep upwelled waters to the sun lit surface layers where primary production takes place

different communities different perspectives issues affecting residents response to a volcanic eruption in southern iceland this research investigates residents knowledge and perception of the katla volcano and emergency response procedures in all rural and urban communities located in the eastern and southern katla hazard zones using a questionnaire survey conducted in 2008 we demonstrate that there is an apparent difference between rural and urban communities knowledge and perceptions and identify some of the issues influencing residents perspectives and behaviour all rural and most urban residents have an accurate knowledge of katla the proposed warning system and emergency response plan urban residents perceived the emergency response plan to be appropriate in comparison rural residents did not perceive the emergency response plan as appropriate rural residents stated that they would personally assess the situation before deciding on a course of action independent of the proposed plan livelihood connections and inherited knowledge affect rural residents ability and willingness to comply with the recommended procedures factors such as hazard knowledge sense of community and attachment to place indicate that rural residents are more resilient to volcanic hazards based on our findings we recommend that emergency management agencies consider issues such as personal responsibility neighbourliness and community involvement and cooperation to develop and implement more appropriate volcanic risk mitigation strategies in light of the recent eyjafjallajokull eruptions we provide a brief discussion on the 2010 emergency response although our findings are iceland specific our recommendations may be applied internationally to other volcanic and disaster prone regions

neutron absorption constraints on the composition of 4 vesta global maps of the macroscopic thermal neutron absorption cross section of vesta s regolith by the gamma ray and neutron detector grand on board the nasa dawn spacecraft provide constraints on the abundance and distribution of fe ca al mg and other rock forming elements from a circular polar low altitude mapping orbit grand sampled the regolith to decimeter depths with a spatial resolution of about 300 km at this spatial scale the variation in neutron absorption is about seven times lower than that of the moon the observed variation is consistent with the range of absorption for howardite whole rock compositions which further supports the connection between vesta and the howardite eucrite and diogenite meteorites we find a strong correlation between neutron absorption and the percentage of eucritic materials in howardites and polymict breccias which enables petrologic mapping of vesta s surface the distribution of basaltic eucrite and diogenite determined from neutron absorption measurements is qualitatively similar to that indicated by visible and near infrared spectroscopy the rheasilvia basin and ejecta blanket has relatively low absorption consistent with mg rich orthopyroxene based on a combination of fe and neutron absorption measurements olivine rich lithologies are not detected on the spatial scales sampled by grand the sensitivity of grand to the presence of mantle material is described and implications for the absence of an olivine signature are discussed high absorption values found in vesta s dark hemisphere where exogenic hydrogen has accumulated indicate that this region is richer in basaltic eucrite representative of vesta s ancient upper crust

the martian surface as imaged sampled and analyzed by the viking landers the two viking landers touched down on the surface of mars in july and september of 1976 viking lander 1 renamed the mutch memorial station mms continued to operate for 3 martian years in chryse planitia the landing site is a rolling sparsely cratered plain impact crater size frequency distributions demonstrate that only meters of vertical erosion have occurred over the lifetime of the surface the site exhibits bedrock exposures numerous rocks excavated during cratering events indurated fine grained sediment blocky material mixed with dust and lithic fragments and aeolian drifts that overlie the blocky material and which probably accumulated during global dust storms lander 2 operated for approximately 2 martian years in utopia planitia a region subjected to volcanic impact aeolian and periglacial phenomena lander 2 is located west of the 100 km diameter crater mie on or near the distal end of the continuous ejecta deposits polygonal ground suggests that desiccation or freeze thaw processes have occurred the lander 2 site exhibits numerous rocks excavated from craters and exposed by erosion set in a matrix of crusty to cloddy sediment rare aeolian drifts overlie the crusty to cloddy material lander multispectral imaging of sediment exposures at both sites is best matched with iron rich claylike weathering products called palagonites the spectral characteristics are probably governed by thin deposits of dust from global and local dust storms darkest rocks have reflectance values that match iron rich igneous rocks although most rocks are covered with indurated coatings of the palagonitelike products chemical compositions of sediments at the two landing sites are strikingly similar suggesting an aeolian origin the compositions suggest an iron rich igneous source rock and are matched by an assemblage of clays and salts samples of blocky materials were found to have about 50 more cl and so3 than other samples implying cementation by salts the magnetic component in the sediment is silt sized or finer and may be maghemite or ultrafine grained hematite no indigenous organic compounds were found the materials were found to be highly reactive releasing o2 when h2o was added oxidizing organic nutrients on board the landers and fixing atmospheric co2 clay to silt sized particles were inferred for drift and crusty to cloddy materials no terrestrial samples have been found that replicate all the attributes of the viking samples approximately 10 m of h2o ice accumulated during both winters at lander 2 and each time evaporated over approximately 200 martian days thin layers of bright red dust from global and local dust storms accumulated at both sites during the first 2 martian years during the third winter strong winds generally scoured the mms site leaving behind a darker aeolian lag deposit bedrock at both sites formed billions of years ago and rocks have been generated and weathered slowly over geologic time but aeolian sediments accumulate become cemented and are subsequently eroded over time spans of millions of years or less the lifetime of the sedimentary deposits at the landing sites may be governed by the 105 to 106 year variations in climate due to quasi periodic changes in obliquity eccentricity and spin axis orientation

an inversion of the estuarine circulation by sluice water discharge and its impact on suspended sediment transport abstract the wadden sea is characterized by a complex topography of branching channels and intertidal flats in which the interplay between fresh water discharges wind forcing and the tidal current causes sediment transport rates and direction to be highly variable in space and time during three field campaigns indications of a negative estuarine circulation have been found in a channel adjacent to the coast in the western dutch wadden sea contrary to the classical picture of estuarine circulation a periodic density stratification was observed that builds up during flood and breaks down during ebb this can be related to a large freshwater source at the mouth of the channel the sluice in kornwerderzand in this study observations of this phenomenon are presented and with the help of a numerical model the different drivers for residual suspended matter transport in this area namely tidal asymmetries in the current velocity and the above mentioned periodic stratification are investigated it is found that the residual current in the area of interest points in ebb direction caused by both the elongated ebb flow phase and the periodic stratification on the contrary the stronger flood currents cause a transport of suspended matter in flood direction this transport is counteracted and therefore diminished by the effects of the sluice discharge

participatory methods of incorporating scientific with traditional knowledge for volcanic hazard management on ambae island vanuatu ambae island is the largest of vanuatu s active volcanoes it is also one of the nation s potentially most dangerous with 60 million m 3 of lake water perched at over 1340 m in the summit caldera and over the ac tive vent in 1995 small phreatic explosions earthquake swarms and heightened gas release led to calls for evacuation preparation and community volcanic hazard awareness programs for the 9500 inhabitants differences in perspective or world view between the island dwellers adhering to traditional beliefs kastom and external sci entists and emergency managers led to a climate of distrust following this crisis in an attempt to address these issues rebuild dialogue and respect between communities out side scientists and administrators and move forward in volcanic hazard education and planning for ambae we adapted and applied participatory rural appraisal pra approaches initial gender segregated pra exercises from two representative communities provided a mechanism for cataloguing local traditional viewpoints and hazard per ceptions ultimately by combining elements of these viewpoints and perceptions with science based manage ment structures we derived volcanic hazard management guidelines supported by an alert system and map that were more readily accepted by the test communities than the earlier top down plans imposed by outside govern mental and scientific agencies the strength of pra ap proaches is that they permit scientists to understand important local perspective issues including visualisations of volcanic hazards weaknesses in internal and external communication systems and gender and hierarchy con flicts all of which can hinder community emergency management the approach we describe has much to offer both developing and industrialised communities that wish to improve their awareness programs and mitigative planning this approach should also enhance communi cation and understanding between volcanologists and the communities they serve

compositional variability on the surface of 4 vesta revealed through grand measurements of high energy gamma rays measurements of the high energy gamma ray flux emanating from asteroid 4 vesta by the dawn gamma ray and neutron detector grand have revealed variability in the near surface elemental composition of the vestan surface these observations are consistent with the presence of large 8 104 km2 regions with distinct hed like elemental compositions the results agree broadly with other global measurements such as the macroscopic neutron absorption cross section and spectral reflectance derived mineralogic maps two distinct regions with eucrite like elemental compositions have been identified the first located primarily within the lucaria and marcia quadrangles and the second within oppia quadrangle the former region is collocated with some of the oldest most heavily cratered terrain on vesta the interior of the 500 km diameter rheasilvia impact basin is found to have a composition that is consistent with diogenite like material taken together these observations support the hypothesis that vesta s original crust was composed of basaltic outflows in the form of eucritic like material and that the rheasilvia basin forming impact exposed lower crustal diogenite like material these measurements also constrain the maximum amount of mesosiderite like material to 10 for each 15 15 surface element

martian high latitude permafrost depth and surface cover thermal inertia distributions 1 martian high latitudes have thermal properties consistent with an extensive high thermal inertia permafrost layer near the surface surface cover thermal inertias and permafrost depths at martian high latitudes 50 80 n s are derived from thermal emission spectrometer tes data and compared with previously published water ice depths determined from the mars odyssey neutron spectrometer mons the depth to the permafrost layer is correlated with surface cover thermal inertia albedo and latitude in general agreement with predicted trends of water ice stability comparison of permafrost depths with water ice rich layer depths derived from mons data displays good qualitative agreement although a divergence is present at greater burial depths this disparity may be due to the presence of hydrated minerals at shallow depths or a lower than expected permafrost thermal inertia corresponding with low water ice concentrations at greater depths surface cover thermal inertias are greater in the northern high latitudes than in the south and differences between these and previous results will have significant effects on the predicted depth of martian water ice stability several regions in the northern hemisphere display high surface cover thermal inertia associated with possible receding water ice deposits that are shallow enough to influence diurnal surface temperatures significant lateral and vertical heterogeneity in water ice distributions are present and the martian regolith is likely more complicated than can be described by simple two layered models and a single mode of water ice emplacement

enhanced hydrogen at the lunar poles new insights from the detection of epithermal and fast neutron signatures 1 the lunar prospector lp and lunar reconnaissance orbiter lro orbital neutron spectroscopy data sets represent a unique comprehensive multimission lunar resource a rigorous statistical approach has been used to re analyze neutron data from both missions to provide new details regarding the relationships between the individual detector data sets as well as a new evaluation of enhanced hydrogen deposits at the lunar poles using the multimission epithermal neutron data set we find water ice distributed broadly across the poles but showing evidence for a dependence on topographical features a footprint averaged water equivalent hydrogen weh abundance of 106 11 ppm at each pole with maxima of 131 and 112 ppm at the north and south poles respectively is derived from the epithermal neutron data we also report the first definitive detection of a fast neutron signature consistent with an enhanced hydrogen hypothesis these data suggest a highly localized distribution consistent with shackleton crater corresponding to a footprint averaged weh abundance of 194 11 if confined to this crater this abundance yields a localized deposit of 0 7 weh details of the analysis approach are presented along with spatial distribution maps showing the intriguing enhanced hydrogen deposits at the lunar poles

driven by excess climatic implications of new global mapping of near surface water equivalent hydrogen on mars abstract we present improved mars odyssey neutron spectrometer mons maps of near surface water equivalent hydrogen weh on mars that have intriguing implications for the global distribution of excess ice which occurs when the mass fraction of water ice exceeds the threshold amount needed to saturate the pore volume in normal soils we have refined the crossover technique of feldman et al 2011 by using spatial deconvolution and gaussian weighting to create the first globally self consistent map of weh at low latitudes our new maps indicate that weh exceeds 15 in several near equatorial regions such as arabia terra which has important implications for the types of hydrated minerals present at low latitudes at high latitudes we demonstrate that the disparate mons and phoenix robotic arm ra observations of near surface weh can be reconciled by a three layer model incorporating dry soil over fully saturated pore ice over pure excess ice such a three layer model can also potentially explain the strong anticorrelation of subsurface ice content and ice table depth observed at high latitudes at moderate latitudes we show that the distribution of recently formed impact craters is also consistent with our latest mons results as both the shallowest ice exposing crater and deepest non ice exposing crater at each impact site are in good agreement with our predictions of near surface weh overall we find that our new mapping is consistent with the widespread presence at mid to high martian latitudes of recently deposited shallow excess ice reservoirs that are not yet in equilibrium with the atmosphere

thermal stratification in saldanha bay south africa and subtidal density driven exchange with the coastal waters of the benguela upwelling system a study was conducted to understand the mechanisms driving observed subtidal variability in the stratification of saldanha bay located in the southern benguela system it was found that the 6 8 day period variability in bay stratification was caused by the inflow and outflow of cold upwelled water driven by changing baroclinic pressure gradients between the coastal and bay domains the direction and magnitude of the pressure gradients were governed by coastal upwelling activity and a lag in the response of the bay to changes in density structure in the coastal ocean when the pressure gradients were bayward and cold water was being driven into the bay the cycle was termed to be in an active phase and the reverse was termed the relaxation phase the upwelling favourable equatorward wind stress impacted the bay stratification in two ways on the regional scale wind drives upwelling and governs the inflow outflow of cold upwelled bottom water which strengthens stratification conversely on the local bay scale wind drives vertical mixing which weakens stratification a four phase model is used to describe the observed variability in stratification in the bay the associated density driven exchange flows are capable of flushing the bay in 6 8 days about one third of the time for tidal exchange alone c 25 days these inflows of cold bottom water are ecologically critical as they supply nutrients to the bay and thus impose a control on new production within the bay environment further ecological implications of this bay ocean exchange include export of phytoplankton new production to the coast limitation of the risk of harmful algal blooms habs and the division of the system into two distinct ecosystems bay and lagoon 1999 academic press

surface waters of the nw iberian margin upwelling on the shelf versus outwelling of upwelled waters from the rias baixas abstract a set of hydrographic surveys were carried out in the ria of vigo nw spain at 2 4 d intervals during four 2 3 week periods in 1997 covering contrasting seasons residual exchange fluxes with the adjacent shelf were estimated with a 2 d non steady state salinity temperature weighted box model exchange fluxes consist of a steady state term dependent on the variability of continental runoff and a non steady state term dependent on the time changes of density gradients in the embayment more than 95 of the short time scale variability of the exchange fluxes in the middle and outer ria can be explained by the non steady state term that in turns is correlated r 2 75 with the offshore ekman transport conversely 96 of the variability of exchange fluxes in the inner ria rely on the steady state term the outer and middle ria are under the direct influence of coastal upwelling which enhances the positive residual circulation pattern by an order of magnitude from 10 2 to 10 3 m 3 s 1 on the contrary downwelling provokes a reversal of the circulation in the outer ria the position of the downwelling front along the embayment depends on the relative importance of ekman transport q x m 3 s 1 km 1 and continental runoff r m 3 s 1 when q x r 7 2 the reversal of the circulation affects the middle ria our results are representative for the rias baixas four large coastal indentations in nw spain during the upwelling season spring and summer 60 of shelf surface waters off the rias baixas consist of fresh eastern north atlantic central water enacw upwelled in situ the remaining 40 consists of upwelled enacw that previously enters the rias and it is subsequently outwelled after thermohaline modification during the downwelling season autumn and winter 40 of the warm and salty oceanic subtropic surface water which piled on the shelf by the predominant southerly winds enters the rias

equatorial locations of water on mars improved resolution maps based on mars odyssey neutron spectrometer data abstract we present a map of the near subsurface hydrogen distribution on mars based on epithermal neutron data from the mars odyssey neutron spectrometer the map s spatial resolution is approximately improved two fold via a new form of the pixon image reconstruction technique we discover hydrogen rich mineralogy far from the poles including 10 wt water equivalent hydrogen weh on the flanks of the tharsis montes and 40 wt weh at the medusae fossae formation mff the high weh abundance at the mff implies the presence of bulk water ice this supports the hypothesis of recent periods of high orbital obliquity during which water ice was stable on the surface we find the young undivided channel system material in southern elysium planitia to be distinct from its surroundings and exceptionally dry there is no evidence of hydration at the location in elysium planitia suggested to contain a buried water ice sea finally we find that the sites of recurring slope lineae rsl do not correlate with subsurface hydration this implies that rsl are not fed by large near subsurface aquifers but are instead the result of either small

theology and disaster studies the need for dialogue abstract in hazard analysis the conventional wisdom holds that disasters are features of either human vulnerability and or de moralised nature the notion of the act of god has been almost completely replaced using examples of volcanic eruptions and christian theology it is argued that many actual and potential victims of hazards continue to explain losses in theistic terms even in societies where individuals are aware of alternative scientific and social explanations in christianity attempts to reconcile god s love justice and omnipotence on the one hand and human suffering on the other is termed theodicy and it is proposed that recent developments allow more fruitful dialogue to take place between hazard analysts and theologians than has been the case hitherto during the international decade for natural disaster reduction 1990 2000 a consensus emerged that if responses to disaster are to be successfully managed then an awareness of local culture is vitally important this consensus has continued as research agendas are currently being formulated for the international strategy for disaster reduction in many disaster prone regions religion is an essential element of culture and must be carefully considered in the planning process and not simply dismissed as a symptom of ignorance superstition and backwardness

vertical distribution of hydrogen at high northern latitudes on mars the mars odyssey neutron spectrometer 1 neutron leakage currents measured using the mars odyssey neutron spectrometer are used to develop a two layer model of the distribution of hydrogen here parameterized as water equivalent hydrogen weh at high northern latitudes the weh abundance in the upper layer wup was found to range between 1 and about 5 the maximum value of the apparent thickness d of this upper layer peaks at about 60 latitude giving the appearance of zonal bands of enhanced d in both hemispheres this maximum is consistent with an expected transition from weh contained solely in hydrous minerals at lower latitudes to weh contained both in the forms of water ice and water of hydration at high latitudes a strong anti correlation between the weh concentration in the lower layer and apparent depth d at high latitudes is observed and may provide clues to the origin of these deposits

rapid response to coastal upwelling in a semienclosed bay bays estuaries forced by local wind show bidirectional exchange flow when forced by remote q3 wind they exhibit unidirectional flow adjustment to coastal sea level acoustic doppler current profiler observations over 1 year show that the ria de vigo iberian upwelling responds to coastal wind events with bidirectional exchange flow the duration of the upwelling and downwelling events estimated from the current variability was 3 3 days and 2 6 days respectively vectorial correlations reveal a rapid response to upwelling downwelling in which currents lag local wind by 6 h and remote wind by 14 h less than the ekman spinup 17 8 h this rapidity arises from the ria s narrowness nonrotational local response equatorward orientation additive remote and local wind responses depth greater than the ekman depth penetration of shelf circulation into the interior and vertical stratification shear reinforcing shelf circulation similar rapid responses are expected in other narrow bays where local and remote winds act together and stratification enhances bidirectional flow

the response of delaware s inland bays to ocean forcing sea level and current observations made during a 2 month summer period in delaware s inland bays are used for the examination of the tidal and subtidal variability in the bays to first order the coupled inland bays are found to be forced primarily by coastal sea level fluctuations at both tidal and subtidal frequencies the observations suggest that the systems behave as low pass filters in response to coastal forcing overall tidal variance decreases sharply inside the bays with the semidiurnal tides suffering significantly higher attenuation than the diurnal tides the subtidal variability however experiences no appreciable attenuation within the bays the systems are also found to be only weakly nonlinear in nature a linearized frequency dependent pumping mode model is developed and results indicate that the model adequately describes the first order response of the inland bays to coastal sea level forcing

perceptions of hazard and risk on santorini abstract santorini greece is a major explosive volcano the santorini volcanic complex is composed of two active volcanoes nea kameni and mt columbo holocene eruptions have generated a variety of processes and deposits and eruption mechanisms pose significant hazards of various types it has been recognized that for major european volcanoes few studies have focused on the social aspects of volcanic activity and little work has been conducted on public perceptions of hazard risk and vulnerability such assessments are an important element of establishing public education programmes and developing volcano disaster management plans we investigate perceptions of volcanic hazards on santorini we find that most residents know that nea kameni is active but only 60 know that mt columbo is active forty percent of residents fear that negative impacts on tourism will have the greatest effect on their community in the event of an eruption 43 of residents would try to evacuate the island by plane ferry residents aged 50 have retained a memory of the effects of the last eruption at the island whereas younger residents have no such knowledge we find that dignitaries and municipal officers those responsible for planning and managing disaster response are informed about the history hazards and effects of the volcanoes however there is no emergency plan for the island and there is confusion between various departments civil defense fire police etc about the emergency decision making process the resident population of santorini is at high risk from the hazards associated with a future eruption

comparisons of upwelling and relaxation events in the monterey bay area 1 observations show significant differences in circulation patterns of upwelling and relaxation events that occurred in the monterey bay during two autonomous ocean sampling network field experiments in august 2003 and 2006 during the 2003 experiment circulation exhibited more typical patterns associated with upwelling relaxation the development of the southward flowing jet and pair of cyclonic inside of the bay and anticyclonic outside of the bay circulations during upwelling and the development of the northward flow along the coast during relaxation of winds during the upwelling event of 2006 the southward flow was weaker and shallower than in 2003 the second relaxation event of 2006 was significantly different from the first relaxation event of 2006 and the relaxation event of 2003 a southward flow was present along the entrance to the bay and this southward flow penetrated into the subsurface up to around 50 m at the mooring location two reasons for the observed differences in upwelling and relaxation events of 2003 and 2006 are identified in the paper weaker winds in august 2006 than in august 2003 and strong positive sea surface height anomalies propagating poleward along the coast during 2006 the 2003 field program included an extensive sampling of the bay and surrounding areas with a fleet of underwater gliders while during 2006 program the extensive sampling was conducted in the area of upwelling center to the north of the monterey bay during the 2003 field program the monterey bay model was able to reproduce observed surface and subsurface features with assimilation of glider observations however during the 2006 field program the assimilation of glider data from the upwelling center to the north of the monterey bay had minimal impact on model simulations of observed features to the south of the upwelling center

observations of low frequency variability in great south bay and relations to atmospheric forcing abstract sea level and current data collected around great south bay new york during december 1979 are examined in conjunction with atmospheric data for evidence of wind forced low frequency variability in the bay and on the adjacent shelf the subtidal sea level along the coast was found to be highly coherent from sandy hook to montauk point with a single empirical mode accounted for more than 97 of the total variance these coherent fluctuations were forced primarily by longshore winds along 250 070 t through the coastal ekman effect the sea level within the bay exhibited large and spatially coherent subtidal fluctuations as a result of a strong coupling with the adjacent shelf the characteristic volume exchange associated with this bay shelf coupling was an active simultaneous inflow or outflow through both ends of the bay with fluctuations in excess of 20 cm s 1 in response to the rise or fall of coastal sea level induced by longshore winds

expanded secondary craters in the arcadia planitia region mars evidence for tens of myr old shallow subsurface ice abstract a range of observations indicates widespread subsurface ice throughout the mid and high latitudes of mars in the form of both pore filling and excess ice it is generally thought that this ice was recently emplaced and is not older than a hundred thousand to a few millions of years old based on ice stability and orbital induced climate change we analyze the distribution of subsurface ice in arcadia planitia located in the northern mid latitudes by mapping thermokarstically expanded secondary craters providing additional evidence for extensive excess ice down to fairly low latitudes less than 40 n we further infer the minimum age of this subsurface ice based on the ages of the four primary craters that are thought to be the source of a large portion of these secondaries which yields estimates on the order of tens of millions of years old much more ancient than anticipated this estimated ancient age suggests that ice can be preserved in the shallow subsurface for long periods of time at least in some parts of arcadia planitia where expanded secondary craters are especially abundant we estimate the amount of ice lost to sublimation during crater expansion based on measurements of expanded secondary craters in hirise digital terrain models the loss is equivalent to a volume of ice between 140 and 360 km 3 which would correspond to a global layer of 1 2 5 mm thick we further argue that much more ice at least 6000 km 3 is likely preserved beneath the un cratered regions of arcadia planitia since significant loss of this excess ice would have caused extensive terrain dissection and the removal of the expanded secondary craters both the loss of ice due to secondary crater expansion and the presence of this ice today have implications for the martian climate

preservation of midlatitude ice sheets on mars national science foundation nsf dge 1143953 nasa earth and space sciences fellowship nessf nnx16ap09h nasa mars data analysis program mdap award nnx15am62g

living near volcanoes scoping the gaps between the local community and volcanic experts in southern chile abstract human societies have always inhabited volcanic zones but only recently scientists and decision makers have turned the attention to volcanic risk prevention and reduction despite a growing consensus about the importance of engaging with nearby populations in practice there is little dialogue with them regarding volcanic threats and opportunities we study the experiences impacts and concerns of an indigenous community inhabiting in between two major volcanic systems carran los venados and puyehue cordon caulle regarding past and recent eruptions results show a longstanding cultural and economic interrelationship between people and volcanoes representing both benefits and barriers to development existing local traditional knowledge is necessary but not sufficient to meet people s needs for adequate understanding and forecasting despite community interest on volcanic science and risk reduction important communication and trust gaps with experts persist our findings suggest the importance for scientists to establish collaborative and participatory relationships with local communities and decision makers with the goal of not only reducing negative volcanic impacts and uncertainty but also taking advantage of the potential of volcanic environments to boost local sustainable livelihoods

on the orbital forcing of martian water and co2 cycles a general circulation model study with simplified volatile schemes 1 variations in the martian water and co2 cycles with changes in orbital and rotational parameters are examined using the geophysical fluid dynamics laboratory mars general circulation model the model allows for arbitrary specification of obliquity eccentricity and argument of perihelion as well as the position and thickness of surface ice exchange of co2 between the surface and atmosphere is modeled generating seasonal cycles of surface ice and surface pressure water is allowed to exchange between the surface and atmosphere cloud formation is treated and both cloud and vapor are transported by modeled winds and diffusion exchange of water and co2 with the subsurface is not allowed and radiative effects of water vapor and clouds are not treated the seasonal cycle of co2 is found to become more extreme at high obliquity as suggested by simple heat balance models maximum pressures remain largely the same but the minima decrease substantially as more co2 condenses in the more extensive polar night vapor and cloud abundances increase dramatically with obliquity the stable location for surface ice moves equatorward with increasing obliquity such that by 45 obliquity water ice is stable in the tropics only ice is not spatially uniform but rather found preferentially in regions of high thermal inertia or high topography eccentricity and argument of perihelion can provide a second order modification to the distribution of surface ice by altering the temporal distribution of insolation at the poles further model simulations reveal the robustness of these distributions for a variety of initial conditions our findings shed light on the nature of near surface ice rich deposits at midlatitudes and low latitudes on mars

surface water subduction during a downwelling event in a semienclosed bay the ria de vigo is a bay strongly influenced by upwelling downwelling cycles along the adjacent coast of nw iberia moored and ship board observations during september 2006 showed that subduction initially associated with an estuarine circulation strengthened when a strong downwelling circulation resulting from northward wind over the coastal ocean was generated in the outer ria causing ambient waters to be advected outward in the lower layer incoming surface waters confined the estuarine circulation to the shallow interior and displaced isopleths downward through the water column at 10 m d 1 as the estuarine circulation retreated inward strong flow convergence developed between middle and inner ria in the layer above 15 m while divergence developed beneath the convergence increased through the period of downwelling favorable wind at a rate consistent with the observed isopleth displacement velocities the coefficient of turbulent diffusion kt from a microstructure profiler indicated that mixing was strong in the estuarine circulation and subsequently in the downwelling zone where localized instabilities and temperature salinity inversions were observed during the downwelling concentrations of phytoplankton including potentially harmful species increased especially in the middle and inner ria as a result of inward advection subduction and the ability of the dinoflagellates to maintain their position in the water column by swimming in the course of the 5 day event the water mass of all but the innermost ria was flushed completely and replaced by waters originating in the coastally trapped poleward flow along the atlantic coastline this article is protected by copyright all rights reserved

sharad sounding radar on the mars reconnaissance orbiter 1 sharad shallow radar is a sounding radar provided by agenzia spaziale italiana asi as a facility instrument on the mars reconnaissance orbiter mission its 20 mhz center frequency and 10 mhz bandwidth complement the lower frequency relatively narrower bandwidth capability of the marsis sounding radar a joint italian u s team has guided the experiment development and is responsible for data analysis and interpretation the radar transmits signals at a 700 hz pulse repetition frequency prf and collects reflections from both the surface and near subsurface of mars vertical and horizontal resolutions are respectively 15 m free space and 3 6 km cross track by 0 3 1 km along track the scientific objective of sharad is to map in selected locales dielectric interfaces to at least several hundred meters depth in the martian subsurface and to interpret these results in terms of the occurrence and distribution of expected materials including competent rock soil water and ice a signal to noise ratio of 50 db for a specular surface return is achieved with 10 w of radiated power by using range and azimuth focusing in ground data processing preprocessed data as well as range and azimuth focused data will be formatted according to planetary data system pds standards and be made available from the asi science data center asdc and from the geosciences node of the planetary data system pds important targets for sharad include the polar layered deposits sedimentary stacks especially in terra meridiani buried channel systems buried impact craters volcanic complexes and shallow ice deposits in equilibrium with the atmosphere

human vulnerability in volcanic environments the case of furnas sao miguel azores abstract the need to examine the vulnerability of people to natural hazards in addition to the long established requirement to study extreme events of nature is being increasingly recognised within disaster research following a discussion of the nature of human vulnerability we propose a framework for its analysis within the context of volcanic activity and we exemplify our approach by a detailed study of furnas a village located at the centre of a volcano with the same name on the island of sao miguel in the azores the methods used included in depth interviews with permanent residents n 50 analysis of census records and an examination of the socio economic history of the town the vulnerability of an individual to volcanic hazards involves a complex interaction of elements which in addition to the usual factors taken into account in programmes of hazard reduction e g the nature of the physical threat location and economic situation also comprises his or her social context and a number of physiological and psychological considerations it is argued further that both generally and in the case of furnas the root causes of vulnerability lie in the history and development of society individual decision making is fundamental but takes place within and cannot be separated from this social context vulnerability analysis allows the identification of points where intervention may be successful in reducing the likelihood of suffering in a society it avoids the problem of people s unexpected reactions to invention leading to a changing or even increasing level of vulnerability by studying society rather than just one aspect of volcanic hazard in isolation

two dimensional numerical studies on the effects of water on martian mantle evolution induced by magmatism and solid state mantle convection 1 numerical models of magmatism and mantle convection beneath a stagnant lithosphere are presented to understand how water affects martian mantle evolution magmatism is modeled as an upward permeable flow of the basaltic magma generated by decompression melting first a global partially molten layer gpml develops and generates a basaltic crust a layer of compositionally buoyant residue of melt extraction in the uppermost mantle and a denser layer with a higher content of the basaltic component in the deep mantle the gpml extracts most of the water initially contained in the upper layer but some water remains in the lower layer of the mantle subsequently hot plumes ascend from the lower layer to induce magmatism the water allows plume magmatism to continue for a long duration up to 5 gyr depending on the initial water content and the detail of the initial temperature distribution in the mantle provided that the mantle is initially not too hot just after planetary formation the plume magmatism is sufficiently active to cause significant crustal growth and dehydration of the crust and mantle in the early evolutionary stage when the internal heating is strong the amount of extracted water is equivalent to a water layer of up to several hundred meters in depth water can also enhance the extraction of heat producing elements hpes from the mantle reduce the heat flux from the mantle to the crust and make the lithosphere thicker both crustal growth and dehydration eventually subside as the hpes decay

ferric sulfates on mars a combined mission data analysis of salty soils at gusev crater and laboratory experimental investigations 1 a temporal visible near infrared vis nir spectral variation was observed from tyrone yellowish salty soils based on seven periodic pancam 13 filter observations made by the spirit rover the major change was the reduction of spectral slope from 434 nm to 753 nm based on the results from a set of systematic laboratory experiments on the stability field and phase transition pathway of typical ferric sulfates we suggest that the strong dehydration processes of ferricopiapite either through amorphization or chemical alteration could be the reasons for the spectral changes of tyrone yellowish salty soils excavated from a deep trench the change of soil property suggests that they were originally not in equilibrium with the surface atmospheric conditions that there is a relative humidity rh gradient existing in the upper few tens of centimeters depth below the surface a layer of salt rich regolith beneath the surface will change the underground temperature profile especially to keep a low temperature zone with a small temperature oscillation than diurnal cycle at surface in a salt enriched regolith layer this temperature profile will provide a relatively high rh and small rh variation and thus will facilitate the preservation of hydrous sulfates with high degree of hydration during the moderate obliquity period on mars additionally the sulfates with high degrees of hydration are excellent rh buffers in a local environment the subsurface hydrous sulfates can be the sources for high level of water equivalent hydrogen found at two large equatorial regions on mars by neutron spectrometer on mars odyssey orbiter

the thermal stability of near surface ground ice on mars the existence of subsurface water ice on mars has been predicted in several theoretical studies1 5 but there are no definitive observations of its present distribution geomorphic features on the surface of mars have been widely interpreted as evidence for the presence of ground ice6 12 but many of these features are found at near equatorial latitudes where thermal models have predicted that near surface water ice should not be stable under present climate conditions3 13 14 here i present the results of thermal calculations which show that observed geographic variations in the thermal and reflectance properties of martian soils significantly affect subsurface temperatures my results indicate that in certain regions ground ice deposits could exist much closer to the surface and much closer to the equator than previously thought in the future these deposits could be a valuable resource for human exploration15

people s behaviour in the face of volcanic hazards perspectives from javanese communities indonesia abstract this paper is concerned with the way in which the indonesian people living on the slopes or near active volcanoes behave in the face of volcanic threats it explores the role of three factors in the shaping of this behaviour e g risk perception cultural beliefs and socio economic constraints the paper is mainly based on field data collected during the last 5 years on four volcanoes in central java namely sumbing sindoro dieng and merapi the common assumption that hazard knowledge risk perception and people s behaviour are closely related and conditional on volcanic activity is debatable in the indonesian context factors that play a role in hazard knowledge e g basic knowledge of volcanic processes personal experience of volcanic crisis time lapsed since the last volcanic eruption etc differ from those that influence risk perception indeed local people often underestimate the scientifically or statistically estimated risk this poor risk perception is characterized by an approximate personal representation of the volcanic processes an excess of trust in concrete countermeasures the presence of a physical visual obstructions or cultural beliefs related to former eruptions in addition the commonly acknowledged factors that influence hazard knowledge and or risk perception may be at odds with the non hazard related factors that prompt or force people to live in or to exploit areas at risk these factors may be either socio cultural e g attachment to place cultural beliefs etc or social and socio economical e g standard of living strength of people s livelihoods well being these factors are fundamental in explaining the short term behaviour in the face of a developing threat during a volcanic crisis

modeling the residual circulation of a coastal embayment affected by wind driven upwelling circulation of the ria de vigo nw spain 1 the barotropic and baroclinic nontidal circulations of the ria de vigo nw spain are studied using the three dimensional finite difference model hamsom hamburg shelf ocean model the external forcing acting on the system includes winds freshwater inflow in the inner part of the ria and all over its surface and heat exchange with the atmosphere modeled velocity is compared with data from an aanderaa dcm12 acoustic doppler current meter at one site of the ria and predicted salinity and temperature fields contrasted with seabird conductivity temperature depth data along the main channel of the ria all predicted current salinity and temperature fields are in good agreement with experimental data a new residual circulation pattern of the ria de vigo and its dependence on coastal winds is described according to this pattern the typical estuarine two layer circulation overlays in the outer part of the ria with a lateral circulation resulting in a three dimensional dynamics the lateral circulation is induced by interaction between the southward northward alongshore coastal jet associated with upwelling downwelling winds and the topographic configuration of the ria

hirise observations of new impact craters exposing martian ground ice twenty small new impact craters or clusters have been observed to excavate bright material inferred to be ice at mid latitudes and high latitudes on mars in the northern hemisphere the craters are widely distributed geographically and occur at latitudes as low as 39 n stability modeling suggests that this ice distribution requires a long term average atmospheric water vapor content around 25 precipitable micrometers more than double the present value which is consistent with the expected effect of recent orbital variations alternatively near surface humidity could be higher than expected for current column abundances if water vapor is not well mixed with atmospheric co2 or the vapor pressure at the ice table could be lower due to salts ice in and around the craters remains visibly bright for months to years indicating that it is clean ice rather than ice cemented regolith although some clean ice may be produced by the impact process it is likely that the original ground ice was excess ice exceeding dry soil pore space in many cases observations of the craters suggest small scale heterogeneities in this excess ice the origin of such ice is uncertain ice lens formation by migration of thin films of liquid is most consistent with local heterogeneity in ice content and common surface boulders but in some cases nearby thermokarst landforms suggest large amounts of excess ice that may be best explained by a degraded ice sheet

mars odyssey neutron data 2 search for buried excess water ice deposits at nonpolar latitudes on mars 1 global maps of hydrogen abundance near the surface of mars interpreted as the mass percent of water equivalent hydrogen weh have been generated from measurements of neutron leakage fluxes from mars although these data provide an unambiguous indicator of the presence of weh quantitative details of its magnitude and burial depth depend on the model of the host regolith that is used to interpret the data previous models assumed a spatially uniform surface cover layer having a one to two mass percent of weh and thickness d covering a semi infinite ice rich deposit these assumptions allowed the derivation of the relative proportions of ice and regolith in the lower layer which had been used to create global maps of weh in the near surface in this paper we develop a new method that determines from the mars odyssey neutron spectrometer mons data a self consistent model of the weh content of both the upper and lower layers as well as the thickness d of the upper layer the results of our model suggest that large areas at nonpolar latitudes may contain water ice deposits that have abundances that are larger than can be held by normal pore volumes these deposits are buried less than about 1 m below the surface and may represent buried water ice or high concentrations of hydrous minerals intriguingly the most definitive mons evidence at intermediate latitudes for excess ground ice corresponds to a region of arcadia planitia within which high resolution imaging science experiment hirise has observed fresh icy craters

reinterpretation of the quaternary sedimentary infill of the ria de vigo nw iberian peninsula as a compound incised valley abstract seismic data have been used to investigate the stratigraphy of the galician rias for more than two decades here we present a new interpretation of the sedimentary infill of an incised valley ria de vigo nw iberian peninsula based on high resolution seismic profiles core sediment analysis and radiocarbon 14 c data the new data indicate that the stratigraphic architecture of the galician rias result from multiple incision infill phases and therefore they are reclassified as compound rather than simple incised valleys seven seismic units were identified one of tertiary age u 1 four of pleistocene age u 2 u 5 which are interpreted as 4 th order sequences deposited between mis 11 and mis 2 and late pleistocene u 6 and holocene u 7 units corresponding with post glacial sedimentation the sedimentary infill overlies a highly faulted irregular granitic and metamorphic basement the inherited morphology is shown to be important for controlling the pathway and evolution of the fluvial network as well as preservation of the sedimentary deposits during several glacial interglacial cycles the presence of a rocky barrier at the mouth of the ria is a distinctive feature that conditions sedimentation and exchange of sediment between the ria and the adjacent shelf for the first time faults and tilted blocks affecting late pleistocene mis 3 deposits have been identified the new data presented here provide the opportunity to reconstruct the evolution of the sedimentary infill of a ria with especially high resolution during the last post glacial transgression

water in the martian regolith from omega mars express here we discuss one of the current reservoirs of water on mars the regolith and rocks exposed at the surface this reservoir is characterized by the presence of h2o and oh bearing phases that produce a broad absorption at a wavelength of 3 m in near infrared nir reflectance spectra this absorption is present in every ice free spectrum of the martian surface obtained thus far by orbital nir spectrometers we present a quantitative analysis of the global distribution of the 3 m absorption using the observatoire pour la mineralogie l eau les glaces et l activite omega imaging spectrometer that has been mapping the surface of mars at kilometer scale for more than 10 years based on laboratory reflectance spectra of a wide range of hydrous minerals and phases we estimate a model dependent water content of 4 1 wt in the equatorial and midlatitudes surface hydration increases with latitude with an asymmetry in water content between the northern and southern hemispheres the surface hydration is compared to various parameters albedo dust geological units time relative humidity atmospheric water pressure and in situ measurements performed by phoenix and curiosity to constrain the nature of the reservoir we conclude that the nature of the surface hydration of the martian low latitudes is not adsorbed water but rather more tightly bound water molecules and hydroxyl groups in the structure of the materials of the near top surface a frost related process best explains the implementation of water into and onto the first microns of the high latitude martian regolith

history and anatomy of subsurface ice on mars abstract ice buried beneath a thin layer of soil has been revealed by neutron spectroscopy and explored by the phoenix mars lander it has also been exposed by recent impacts this subsurface ice is thought to lose and gain volume in response to orbital variations milankovitch cycles we use a powerful numerical model to follow the growth and retreat of near surface ice as a result of regolith atmosphere exchange continuously over millions of years if a thick layer of almost pure ice has been deposited recently it has not yet reached equilibrium with the atmospheric water vapor and may still remain as far equatorward as 43 n where ice has been revealed by recent impacts a potentially observable consequence is present day humidity output from the still retreating ice we also demonstrate that in a sublimation environment subsurface pore ice can accumulate in two ways the first mode widely known is the progressive filling of pores by ice over a range of depths the second mode occurs on top of an already impermeable ice layer subsequent ice accumulates in the form of pasted on horizontal layers such that beneath the ice table the pores are completely full with ice most or all of the pore ice on mars today may be of the second type at the phoenix landing site where such a layer is also expected to exist above an underlying ice sheet it may be extremely thin due to exceptionally small variations in ice stability over time

community preparedness for lava flows from mauna loa and hualālai volcanoes kona hawai i lava flows from mauna loa and hual lai volcanoes are a major volcanic hazard that could impact the western portion of the island of hawai i e g kona the most recent eruptions of these two volcanoes to affect kona occurred in a d 1950 and ca 1800 respectively in contrast in eastern hawai i eruptions of neighboring k lauea volcano have occurred frequently since 1955 and therefore have been the focus for hazard mitigation official preparedness and response measures are therefore modeled on typical eruptions of k lauea

estimates of subtidal volume flux in mid chesapeake bay utilizing 20 days of current meter and sea level elevation records taken in two cross sections in mid chesapeake bay an objective interpolation procedure was devised to allow the computation of vertical profiles of the laterally integrated subtidal volume fluxes at each section at 3 h intervals over the period of the experiment the presence of a classical mean estuarine circulation was observed however departures from this gravitational circulation were revealed on a shorter time scale reaching the value of 20 000 m3 s 1 over a day and featuring behaviors of reverse estuarine storage and discharge modes the volume flux computations through each cross section based on the measured current velocities the freshwater inflow and the calculated stokes transport were in agreement with each other a two layered box model of the mean subtidal circulation in the segment of the estuary bound by the two cross sections is offered a comparison was made between the computations of net volume flux into and out of the bay above these sections using two independent methods 1 the accounting of volume continuity based upon direct measurements of volume flux through the sections and 2 the direct calculation of the time rate of change of volume of the upper bay obtained from tide gauge records the agreement between the two results was found to be very good further evidence is provided for the upward phase propagation of the oscillations in the residual motion of estuarine waters

distribution of mid latitude ground ice on mars from new impact craters new impact craters at five sites in the martian mid latitudes excavated material from depths of decimeters that has a brightness and color indicative of water ice near infrared spectra of the largest example confirm this composition and repeated imaging showed fading over several months as expected for sublimating ice thermal models of one site show that millimeters of sublimation occurred during this fading period indicating clean ice rather than ice in soil pores our derived ice table depths are consistent with models using higher long term average atmospheric water vapor content than present values craters at most of these sites may have excavated completely through this clean ice probing the ice table to previously unsampled depths of meters and revealing substantial heterogeneity in the vertical distribution of the ice itself

exchange fluxes between the ria de vigo and the shelf a bidirectional flow forced by remote wind 1 in the ria de vigo western coast of the iberian peninsula the seasonal pattern associated with shelf winds at these latitudes produces upwelling downwelling episodes that affect the residual circulation the aim of this paper is to go deeply into the interaction between remote winds and the dynamics of the ria aided by an inverse model in the galician r ias the box models inverse models have been developed from a two dimensional 2 d point of view since the classical baroclinic residual circulation in positive estuaries has a vertical distribution freshwater outflow through the surface layer and inflow through the bottom layer however recent work in the ria de vigo has shown the existence of a 3 d residual circulation in the seaward region of the ria during upwelling downwelling conditions a coastal jet enters leaves the ria through the northern mouth and leaves enters through the southern mouth the inverse model developed in this paper is a 3 d kinematic box model based on tracer and volume balances with the constraint of nonnegative vertical exchange coefficients the fluxes obtained confirm during some periods the 3 d residual circulation overlying the classical 2 d scheme it is shown how the 3 d pattern affects the inner ria causing transversal differences in the flow field in addition the model results have been helpful in the discussion of a possible barotropic bidirectional flow associated with remote winds the results have set the basis for the existence of a bidirectional flow originated by a barotropic interaction with the shelf upwelling

insights into complex layered ejecta emplacement and subsurface stratigraphy in chryse planitia mars through an analysis of themis brightness temperature data layered ejecta craters on mars have been interpreted to indicate the presence of volatiles in the substrate making them important targets for the investigation of sites of astrobiological significance if the ejecta are associated with the presence of water in the substratum specific surface grain size trends are expected in this study we explore the distribution of grain sizes in the layered ejecta of impact craters located in chryse planitia using thermal emission imaging system themis thermal infrared data ejecta grain size trends in conjunction with ejecta mobility and lobateness values are applied to assess the degree of surface flow of the ejecta and in turn to constrain the plausible volatile abundance cohesion and fine particle content of the target materials craters with a larger fraction of small grain sizes in their ejecta showed greater ejecta mobility and lobateness consistent with a water rich and or a low cohesion target craters displaying decreasing grain size with increasing radius had smaller diameters and lower ejecta mobility and lobateness indicating only a minimal component of surface ejecta flow ejecta grain size trends varied with crater diameter from which the presence of vertical compositional stratigraphy in chryse planitia is inferred and interpreted our observations are synthesized into a number of plausible geologic scenarios for chryse planitia

formation of glaciers on mars by atmospheric precipitation at high obliquity surface conditions on mars are currently cold and dry with water ice unstable on the surface except near the poles however geologically recent glacierlike landforms have been identified in the tropics and the midlatitudes of mars the ice has been proposed to originate from either a subsurface reservoir or the atmosphere we present high resolution climate simulations performed with a model designed to simulate the present day mars water cycle but assuming a 45 obliquity as experienced by mars a few million years ago the model predicts ice accumulation in regions where glacier landforms are observed on the western flanks of the great volcanoes and in the eastern hellas region this agreement points to an atmospheric origin for the ice and reveals how precipitation could have formed glaciers on mars

hydrogen and chlorine abundances in the kimberley formation of gale crater measured by the dan instrument on board the mars science laboratory curiosity rover the dynamic albedo of neutron dan instrument on board the mars science laboratory curiosity rover acquired a series of measurements as part of an observational campaign of the kimberley area in gale crater these observations were planned to assess the variability of bulk hydrogen and neutron absorbing elements characterized as chlorine equivalent concentration in the geologic members of the kimberley formation and in surface materials exposed throughout the area during the traverse of the kimberley area curiosity drove primarily over the smooth hummocky unit a unit composed primarily of sand and loose rocks with occasional stops at bedrock of the kimberley formation during the kimberley campaign dan detected ranges of water equivalent hydrogen weh and chlorine equivalent concentrations of 1 5 2 5 wt and 0 6 2 wt respectively results show that as the traverse progressed dan observed an overall decrease in both weh and chlorine equivalent concentration measured over the sand and loose rocks of the smooth hummocky unit dan measurements of weh and chlorine equivalent concentrations in the well exposed sedimentary bedrock of the kimberley formation show fluctuations with stratigraphic position the kimberley campaign also provided an opportunity to compare measurements from dan with those from the sample analysis at mars sam and the alpha particle x ray spectrometer apxs instruments dan measurements obtained near the windjana drill location show a weh concentration of 1 5 wt consistent with the concentration of low temperature absorbed water measured by sam for the windjana drill sample a comparison between dan chlorine equivalent concentrations measured throughout the kimberley area and apxs observations of corresponding local surface targets and drill fines shows general agreement between the two instruments

magmatic intrusions and deglaciation at mid latitude in the northern plains of mars abstract on earth igneous rocks are generally affected by magmatic differentiation and the volume of intrusive bodies is considered to be 5 10 times larger than the volume of volcanic rocks in contrast in the case of mars the occurrence of olivine phyric basalts at gusev crater mcsween h y 2006 j geophys res planets 111 e10 e02s10 the primitive nature of at least four picritic shergottites grott m 2013 planet space sci 174 49 111 and the chemical composition of major volcanic provinces baratoux d toplis m j monnereau m gasnault o 2011 nature 472 338 341 suggest that primary melts of the mantle may have commonly reached the surface these observations together with sparse morphologic evidence of intrusions in comparison with other terrestrial planets raise the issue of the conditions for the formation and occurrence of sub surface zones of magma storage on mars in this respect a series of two types of young amazonian domes located at mid latitudes in western arcadia planitia east of phlegra montes previously interpreted as surface expressions of intrusive bodies farrand w h lane m d edwards b r yingst r a 2011 icarus 211 139 156 are examined here a fraction of the domes consist of upraised plain material whereas others distinguished by a massive core and a large aspect ratio could be partially exhumed intrusions or extrusions of viscous differentiated magma the latter interpretation is however not compatible with the mafic compositions inferred from orbital visible and near infrared spectroscopic observations the thicknesses and radii of both types of domes appear to be related through a power law relationship with exponents close to 1 or 5 4 these exponent values are not compatible with extrusive morphologies but are characteristic of intrusions magma below an elastic layer michaut c 2011 j geophys res 10 1029 2010jb008108 we conclude that all types of domes are intrusive bodies the large aspect ratios of some of these features may be reconciled with a mafic composition and a shallow emplacement a few hundred meters as well as a relatively large injection rate magma emplacement below an ice rich horizon that was subsequently removed offers a plausible scenario for their partial exhumation this scenario is supported by independent signs of ice removal and deflation events in the northern plains the formation of these intrusions appear therefore to be related to an unusual context of magma ascent below a thick and low density ice rich horizon

an unusual holocene fan shaped subaqueous prograding body at the back of the cies islands ridge ria de vigo nw spain geomorphology facies and stratigraphic architecture abstract the internal structure of a new subaqueous sedimentary body with a 3d morphology of a fan was studied using an interdisciplinary approach based on geophysical geomorphological sedimentological and radiocarbon data the genesis of the sedimentary body is controlled by two main factors 1 the presence of a basement ridge that constitutes the cies archipelago acting as a barrier that protects the ria from high energy marine events and 2 the w sw swell direction under stormy conditions which sweeps the sediment from the platform and introduces it into the ria through the narrow entrance between faro and san martino islands the sedimentary body that has grown inside the ria under low energy conditions progrades in a landward direction from the shelf to the ria sedimentological analysis indicates that the facies associations are coarse grained bioclastics in the proximal areas of this body changing laterally to mixed fine grained sediment in its distal parts the combination of geophysical and radiocarbon data leads us to establish the beginning of the progradation of the sedimentary body subsequent to the younger dryas cold event associated with the holocene sea level rise the seismic analysis of the high resolution seismic records allows us to recognize five main clinoform sets inside the subaqueous prograding sedimentary body which can be attributed to sea level changes during the holocene

short timescale thermohaline variability and residual circulation in the central segment of the coastal upwelling system of the ria de vigo northwest spain during four contrasting periods 1 sixteen hydrographic surveys were carried out in the middle segment of the ria de vigo northwest spain at 3 to 4 day intervals during february april july and september 2002 four surveys per period simultaneously an acoustic doppler current profiler adcp mooring recorded the velocity profile combination of direct current measurements with the output of an inverse model based on the time course of the distributions of salinity and temperature allowed an objective analysis of the effect of the meteorological forces on the hydrodynamics of the ria remote shelf winds explained more than 65 of the variability of the subtidal circulation which responded immediately to this forcing lag time 2 days shelf winds created a simple two layered circulation pattern with a surface outgoing current under northerly winds and a surface ingoing current under southerly winds a three layered circulation developed during the transitions from northerly to southerly winds and vice versa at the same time an empirical orthogonal function eof analysis demonstrated the lack of contribution of local winds to the subtidal dynamics of the ria continental runoff and heat exchange with the atmosphere explained less than 5 and 25 of the variability observed in the subtidal circulation of the ria de vigo

tidal exchange at the bay ocean boundary for bays and inlets with narrow entrances tidal exchange with the ocean is often characterized by an ebb flood asymmetry in which the ebb flow exits the bay as a jet while the flood flow is drawn in approximately as a radial sink a process often termed tidal pumping in this paper the importance of tidal pumping in controlling the exchange of water at the bay ocean boundary is examined based on observations at the mouth of san diego bay the observations are novel in combining the use of shipboard acoustic doppler current measurements with a unique bay water tracer technique to provide visualization of the exchange as well as exchange budgets visualization of the tidal evolution of flow and tracers suggests that in accordance with the classical tidal pumping model the horizontal dynamics at the mouth of san diego bay are governed by an asymmetry between the jet like nature of the ebb flow and the sink like nature of the flood flow this asymmetry results in strong tidal velocity and phase gradients similar to those observed in previous numerical modeling studies a one dimensional trajectory model based on the observations indicates that the combined influence of the residual circulation and offshore gradients in the tidal velocity and phase provides the mechanism by which water from the bay is exchanged with water from the ocean both bottom friction and thermal gradients affect the dynamics of the vertical exchange the resulting asymmetry in the offshore flow leads to a vertical mode of pumping similar to that observed in the horizontal view this horizontal and vertical pumping of the offshore flow is shown to produce a strong correlation between the sectionally averaged velocity and bay water concentration resulting in a significant net tidal exchange between the bay and ocean

analysis of risk assessment factors of individuals in volcanic hazards review of the last decade abstract there are many methods and scientific research approaches where modeling and understanding on how individuals evaluate natural origin risks despite the proficiency and depth of such studies we evidenced a lack for a holistic approach where the most influencing factors in the individual decision making process were covered this research seeks to understand what those factors are how they relate to each other and how the behave with respect to individual perception and acceptance of risk for this we performed a thorough literature review covering the last decade in relation with the understanding of how these incidence factors affected the perception and acceptance of risk in the communities exposed to volcanic events under the decision making process our research was able to detect how the identified variables influenced each other in this process we analyzed different study cases found in the literature and additionally we propose as a further research a new theoretical approach related to decision making modeling process under dynamic system that would be valuable as a contribution to risk management

recent ice rich deposits formed at high latitudes on mars by sublimation of unstable equatorial ice during low obliquity observations from the gamma ray spectrometer instrument suite on the mars odyssey spacecraft have been interpreted as indicating the presence of vast reservoirs of near surface ice in high latitudes of both martian hemispheres1 2 3 4 5 ice concentrations are estimated to range from 70 per cent at 60 latitude to 100 per cent near the poles possibly overlain by a few centimetres of ice free material in most places4 this result is supported by morphological evidence of metres thick layered deposits that are rich in water ice6 7 8 9 and periglacial like features10 11 found only at high latitudes diffusive exchange of water between the pore space of the regolith and the atmosphere has been proposed to explain this distribution12 but such a degree of concentration is difficult to accommodate with such processes9 13 14 alternatively there are suggestions that ice rich deposits form by transport of ice from polar reservoirs and direct redeposition in high latitudes during periods of higher obliquity9 13 but these results have been difficult to reproduce with other models here we propose instead that during periods of low obliquity less than 25 high latitude ice deposits form in both hemispheres by direct deposition of ice as a result of sublimation from an equatorial ice reservoir that formed earlier during a prolonged high obliquity excursion using the ice accumulation rates estimated from global climate model simulations we show that over the past ten million years large variations of mars obliquity have allowed the formation of such metres thick sedimentary layered deposits in high latitude and polar regions

the perception of volcanic risk in kona communities from mauna loa and hualālai volcanoes hawai i abstract volcanic hazards in kona i e the western side of the island of hawai i stem primarily from mauna loa and hual lai volcanoes the former has erupted 39 times since 1832 lava flows were emplaced in kona during seven of these eruptions and last impacted kona in 1950 hual lai last erupted in ca 1800 society s proximity to potential eruptive sources and the potential for relatively fast moving lava flows coupled with relatively long time intervals since the last eruptions in kona are the underlying stimuli for this study of risk perception target populations were high school students and adults n 462 using these data we discuss threat knowledge as an influence on risk perception and perception as a driving mechanism for preparedness threat knowledge and perception of risk were found to be low to moderate on average fewer than two thirds of the residents were aware of the most recent eruptions that impacted kona and a minority felt that mauna loa and hual lai could ever erupt again furthermore only about one third were aware that lava flows could reach the coast in kona in less than 3 h lava flows and ash fall were perceived to be among the least likely hazards to affect the respondent s community within the next 10 years whereas vog volcanic smog was ranked the most likely less than 18 identified volcanic hazards as amongst the most likely hazards to affect them at home school or work not surprisingly individual preparedness measures were found on average to be limited to simple tasks of value in frequently occurring domestic emergencies whereas measures specific to infrequent hazard events such as volcanic eruptions were seldom adopted furthermore our data show that respondents exhibit an unrealistic optimism bias and infer that responsibility for community preparedness for future eruptions primarily rests with officials we infer that these respondents may be less likely to attend to hazard information react to warnings as directed and undertake preparedness measures than other populations who perceive responsibility to lie with themselves there are significant differences in hazard awareness and risk perception between students and adults between subpopulations representing local areas and between varying ethnicities we conclude that long time intervals since damaging lava flows have occurred in kona have contributed to lower levels of awareness and risk perceptions of the threat from lava flows and that the on going eruption at k lauea has facilitated greater awareness and perception of risk of vog but not of other volcanic hazards low levels of preparedness may be explained by low perceptions of threat and risk and perhaps by the lack of a clear motivation or incentive to seek new modes of adjustment

recent formation and evolution of northern martian polar layered deposits as inferred from a global climate model 1 we present a time marching model which simulates the exchange of water ice between the martian northern cap the tropics and a high latitude surface reservoir net annual exchange rates of water and their sensitivity to variations in orbital rotational parameters are examined using the martian water cycle modeled by the lmd three dimensional global climate model these rates are propagated over the last 10 myr to follow the thickness of the reservoirs the effect of a sublimation dust lag is taken account to test simple models of layer formation periods of high mean polar summer insolation 5 10 ma ago lead to a rapid exhaustion of a northern polar cap and a prolonged formation of tropical glaciers the formation of a northern cap and of a high latitude icy mantle may have started 4 ma ago with the average decrease of polar insolation tropical ice may have disappeared around 2 7 ma ago but small glaciers could have formed during the last peaks of polar summer insolation over the last 4 myr most of the present cap may have formed at the expense of tropical and high latitude reservoirs forming distinct layers at almost each 51 kyr 120 kyr insolation cycle layers thickness ranges from 10 to 80 m variations being produced by the modulation of the obliquity with 2 4 and 1 3 myr periods because only 30 insolation cycles have occurred since 4 ma ago we found an inconsistency between the recent astronomical forcing the observed number of layers and simple astronomically based scenarios of layers formation

alternative paradigms of volcanic risk perception the case of mt pinatubo in the philippines the literature on people s response to volcanic hazards tends to be split between two paradigms the first argues that the choice of adjustment depends on how people perceive rare and extreme volcanic phenomena and the associated risk the second considers that people s behavior in the face of natural hazards is constrained by social economic and political forces beyond their control the present paper addresses both paradigms and demonstrates that in order to understand people s behavior in the face of volcanic threats volcanic risk perception has to be balanced with non hazard related factors and structural constraints these conclusions are based on a case study of mt pinatubo and the lingering threat of lahars from the 1991 eruption drawing on the results of a questionnaire based survey and additional interviews with key informants it is shown that a high perception of risk does not stop people from choosing to forms of living that put them at high threat from lahars furthermore the paper argues that insufficient opportunity for making a livelihood in resettlement centers and strong attachment to native villages push people back to the banks of lahar channels everyday hazards of poverty and the threat to cultural heritage weighed heavier than this seasonal natural hazard in other words in a context of economic and social hardship risk perception of volcanic hazards is necessarily balanced with other risk perceptions this study does not argue that risk perception is unimportant for understanding people s adjustment to volcanic environments but rather stresses the need for placing it in its larger and daily contexts which are independent of volcanic hazards

h layering in the top meter of mars we explore the capability of a method of mapping the depth distribution of a hydrogen rich layer in the top meter of mars from the neutron currents measured by the mars odyssey neutron spectrometer assuming the soil can be modeled by two layers of known composition having different hydrogen contents simulations allow an inversion of the neutron data into knowledge of depth and hydrogen content of the lower layer the determination of these variables is sensitive to the hypothesis of chemical composition of the soil we quantify this contribution to the uncertainty in the method first in terms of individual chemical elements and then in terms of macroscopic absorption cross sections to minimize this source of error an average composition was inferred from mars exploration rover data possible compositions having a wide range of macroscopic absorption cross sections were used to evaluate the uncertainty associated with our calculations we finally compare our results to ice table depth estimates predicted by two published theoretical models at locations where the composition is relatively well known the fit is excellent in the southern high latitudes but questionable in the northern high latitudes possible explanations of these differences include the high geographical variations of the neutron currents relative to the spatial width of the response function of the instrument and the overly simple model we of necessity used for surface layering

new and extended data processing of mars odyssey neutron spectrometer data abstract the los alamos national laboratory designed and built mars odyssey neutron spectrometer mons has been operating and collecting data from february 2002 to the present mons measures the neutron leakage albedo from galactic cosmic ray bombardment of mars these signals can indicate the presence of near surface water deposits on mars and can also be used to study properties of the seasonal polar co2 ice caps this work outlines a new analysis of the mons data that results in new and extended time series maps of mons thermal and epithermal neutron data the new data are compared to previous publications on the mons instrument we then present preliminary results studying the inter annual variability in the polar regions of mars based on 8 mars years of mons data from the new dataset

rationalising a volcanic crisis through literature montserratian verse and the descriptive reconstruction of an island abstract this article discusses a selection of the literary output provoked and inspired by the eruption of soufriere hills volcano on montserrat notably poetry and prose written by montserratians affected by the disaster it argues that literature can be a source of local knowledge and a window into a culture that is seeking to deal with a tragedy it can also be used to assess outreach efforts and to investigate the impact of volcanic events and of volcanological information on local populations the texts describe the process by which montserratians moved from bewilderment and denial to renewal and re identification and even pride in the volcanic activity and their own ability to live with it and to help prepare other caribbean islands for future volcanic events literature looks both backwards and forwards communicating the acts of experiencing and changing on montserrat that applies both to colonialism and the role of the uk in montserrat s political economic and social life and also to the importance of learning volcanology and welcoming volcanologists as a means of survival

ground ice at the phoenix landing site stability state and origin 1 a primary objective of the phoenix mission was to examine the characteristics of high latitude ground ice on mars we report observations of ground ice its depth distribution and stability characteristics and examine its origins and history high latitude ground ice was explored through a dozen trench complexes and landing thruster pits over a range of polygon morphological provinces shallow ground ice was found to be abundant under a layer of relatively loose ice free soil with a mean depth of 4 6 cm which varied by more than 10x from trench to trench these variations can be attributed mainly to slope effects and thermal inertia variations in the overburden soil affecting ground temperatures the presence of ice at this depth is consistent with vapor diffusive equilibrium with respect to a mean atmospheric water content of 3 4 1019 m 3 consistent with the present day climate significant ice heterogeneity was observed with two major forms ice cemented soil and relatively pure light toned ice ice cemented soils which comprised about 90 of the icy material exposed by trenching are best explained as vapor deposited pore ice in a matrix supported porous soil light toned ice deposits represent a minority of the subsurface and are thought to consist of relatively thin near surface deposits the origin of these relatively pure ice deposits appears most consistent with the formation of excess ice by soil ice segregation such as would occur by thin film migration and the formation of ice lenses needle ice or similar ice structures

subtidal sea level and current variations in the northern reach of san francisco bay abstract analyses of sea level and current meter data using digital filters and a variety of statistical methods show a variety of phenomena related to non local coastal forcing and local tidal forcing in the northern reach of san francisco bay a partially mixed estuary low frequency variations in sea level are dominated by non local variations in coastal sea level and also show a smaller influence from tidally induced fortnightly sea level variations low frequency currents demonstrate a gravitational circulation which is modified by changes in tidal current speed over the spring neap tidal cycle transients in gravitational circulation induce internal oscillations with periods of two to four days

erratum analysis of risk assessment factors of individuals in volcanic hazards review of the last decade journal of volcanology and geothermal research 2018 357 254 260 s0377027318300465 10 1016 j jvolgeores 2018 05 009

the 2007 eruption of kelut volcano east java indonesia phenomenology crisis management and social response we focus in this paper on the processes and consequences of an unusual volcanic eruption at kelut volcano east java in november 2007 after two months of worrying precursor signs kelut volcano erupted but neither explosions nor the usual hazards observed during the historic eruptions happened e g ash falls volcanic bombs and pyroclastic flows instead of an explosive eruption the 2007 eruption was extrusive given than such an eruption could not be predicted the authorities had to manage a new situation we conducted interviews with nine stakeholders of the crisis management team and undertook a questionnaire based survey in the settlement nearest to the crater in order to understand how the authorities managed the crisis and how people reacted inquiries and questionnaires were carried out shortly after the end of the evacuation process when the volcano was still under surveillance for fear of an explosive phase the results display a real gap in what it takes to manage a crisis or live through a crisis this suggests that the unusual eruption pattern of kelut volcano was not the only factor of the misunderstanding between the authorities and the population these problems stem from more structural causes such as the lack of communication and information when there is a need to adapt to a new scenario in such a situation the inability of the crisis management system to take decisions underscored the intrinsic vulnerability of the population despite a hierarchical and strategic top down crisis management approach

the presence and stability of ground ice in the southern hemisphere of mars abstract we calculate new estimates of ground ice stability and the depth distribution of the ice table the depth boundary between ice free soil above and ice cemented soil below and compare these theoretical estimates of the distribution of ground ice with the observed distribution of leakage neutrons measured by the neutron spectrometer instrument of the mars odyssey spacecraft s gamma ray spectrometer instrument suite our calculated ground ice distribution contains improvements over previous work in that we include the effects of the high thermal conductivity of ice cemented soil at and below the ice table we include the surface elevation dependence of the near surface atmospheric humidity and we utilize new high resolution maps of thermal inertia albedo and elevation from mars global surveyor observations results indicate that ground ice should be about 5 times shallower than in previous predictions while results are dependent on the atmospheric humidity depths are generally between a few millimeters and a few meters with typical values of a few centimeters results are also geographically similar to previous predictions with differences due to the higher resolution of thermal inertia and the inclusion of elevation effects on humidity comparison with the measured epithermal neutron count rates in the southern hemisphere indicate that the geographic distribution of the count rate is best correlated with ground ice in equilibrium with 10 to 20 pr m precipitable micrometers column abundance of atmospheric water assuming a uniform distribution with co2 however given the uncertainties 5 to 30 pr m also may be viable this water abundance represents a longer term average over 100 to 1000 yr there is a high degree of correlation between the depth of the ice table and the epithermal count rate that agrees remarkably well with predicted count rates as a function of ice table depth these results indicate that ground ice in the upper meter of the martian soil is in diffusive equilibrium with the atmosphere since ground ice in this depth zone is expected to undergo saturation desiccation cycles with orbital variations this ice should be younger than about 500 kyr and was emplaced under similar cold and dry climate conditions of today remaining differences between the predicted depths of the ice table and those inferred from the neutron data are likely to be due to subpixel heterogeneity in the martian surface including the presence of rocks slopes and patches of soil with varying thermophysical properties