application of uav bvlos remote sensing data for multi faceted analysis of antarctic ecosystem abstract a photogrammetric flight was performed in december 2016 as bvlos beyond visual line of sight operation over penguin island south shetland islands western antarctica images were taken by the pw zoom fixed wing uav equipped with a digital slr canon 700d camera the flight was performed at 550 m asl and covered a total distance of 231 58 km the plane take off and landing site was near the h arctowski polish antarctic station arctowski on king george island south shetlands the main aim of the mission was to collect environmental data to estimate the size of penguin and pinniped breeding populations and to map vegetation cover and landforms the plane returned to arctowski with 1630 images of penguin island with the ground sample distance gsd lower than 0 07 m the analysis of developed ortophoto allowed us to locate and identify individuals of two penguin species adelie and chinstrap and individuals of two species of pinnipeds southern elephant seal and weddell seal three types of tundra communities were mapped together with numerous landforms such as volcanic mass movement fluvial coastal and aeolian ones the uav bvlos photogrammetric operation proved to be very robust in gathering valuable qualitative and quantitative data necessary for monitoring distant and isolated polar environments

geoenvironmental characterization of unstable abandoned mine tailings combining geophysical and geochemical methods cartagena la union district spain abstract this study presents the results of the geoenvironmental characterization of the brunita mine pond in the cartagena la union mining district murcia se spain the main objective was to evaluate the present conditions of the mine tailings in order to identify related environmental hazards since 1956 the brunita mine tailings were being stored in four stepped ponds at the watercourse of a nno sse trending ravine subsequently they were stored in a single large pond after the closure of the pond operations certain work on dike stabilization was performed and debris from the brunita mine started to accumulate the mining works for 50 years have led to the complete burial of the surrounding valleys and hills by mine waste material electrical resistivity tomography ert has allowed the determining of both the general geometry of the pond base and the thickness of the mine tailings surveys along a total of 6 ert profiles 3 longitudinal and 3 transverse profiles to the largest dimension of the pond were carried out the strong resistivity contrast between the infilling and the bedrock is high enough to clearly define the bottom pond boundary low resistivity values 200 m correspond to the paleozoic rocks that constitute the base of the deposit vertical steps have been recognized defining strong variations in the thickness of the deposit this geometry results from the interaction between the paleotopography of the previous valley and the different growth stages of the deposit the depth of the pond s base obtained from two boreholes has confirmed the results obtained from ert profiles significant amounts of pyrite and siderite and an appreciable presence of sphalerite and galena were determined by xrd of representative samples accordingly high contents of toxic metals cd cu pb sn and zn and as were detected in chemical analyses which show the potential of the tailings to release substantial amounts of these pollutants into the surrounding soils and watercourses amd has been identified and percolation through the base of the pond could occur at its northeast sector where a low resistivity area is recognized the manifest instability of the tailings pond makes it necessary to include physical stabilization in remediation and monitoring in order to minimize the environmental impact of the tailings on the areas affected which is located in one of the most popular tourist areas in se spain

circulation and teleconnection mechanisms of northeast brazil droughts abstract the northern nordeste of brazil has its short rainy season narrowly concentrated around march april when the interhemispheric southward gradient of sea surface temperature sst is weakest and the intertropical convergence zone itcz which is the main rainbearing system for the nordeste reaches its southernmost position in the course of the year the recurrent secas droughts have a severe socio economic impact in this semi arid region in drought years the pre season october january rainfall is scarce the interhemispheric sst gradient weakened and the basin wide southerly northerly wind component enhanced reduced all manifestations of an anomalously far northward itcz position apart from this ensemble of atlantic indicators the secas also tend to be preceded by anomalously warm equatorial pacific waters in january during el nino years an upper tropospheric wave train extends from the equatorial eastern pacific to the northern tropical atlantic affecting the patterns of upper tropospheric topography and divergence and hence of vertical motion over the atlantic the altered vertical motion leads to a weaker meridional pressure gradient on the equatorward flank of the north atlantic subtropical high and thus weaker north atlantic tradewinds the concomitant reduction of evaporation and wind stirring allows for warmer surface waters in the tropical north atlantic and thus steeper interhemispheric meridional thermal gradient consequently the itcz stays anomalously far north and the nordeste rainy season becomes deficient

a proxy for snow cover and winter ground surface cooling mapping usnea sp communities using high resolution remote sensing imagery maritime antarctica usnea sp formations show a spatial distribution coinciding with wind exposed locations on rock knobs or sedimentary bodies while they are commonly absent from concave sites field collection of georeferenced ground truthing data in the meseta norte fildes peninsula maritime antarctica and the application of supervised classification techniques over a summer high resolution quickbird satellite scene showed excellent classification accuracy for the different landcover types the results show that usnea formation distribution maps are a viable proxy for areas with less snow during the cold season such an approach provides input for permafrost and active layer modelling since snow acts as a critical control on ground surface heat balance since snow mapping is extremely difficult in maritime antarctica our tested approach provides important added value for empirical statistical modelling of permafrost distribution

geometry of propagating continental rifts reconstruction of past plate configurations through palinspastic restoration of continental margins1 4 requires a detailed knowledge of the geometries of horizontal continental extension extension is often restricted to discrete linear zones termed rifts5 6 and rift models that invoke propagating vertical dykes and cracks7 10 are useful for assessing the relative significance and timing of uplift subsidence and extension in the tectonic evolution of rift basins however many models do not adequately account for the observed asymmetry of rifts i describe here the general three dimensional character of young and aborted continental rifts which can be used to derive a structural model for the propagation of rifts in continental lithosphere the rifts become asymmetric as a consequence of the role played by low angle normal faults in the overall rift geometry

prediction of tropical atlantic sea surface temperatures using linear inverse modeling the predictability of tropical atlantic sea surface temperature on seasonal to interannual timescales by linear inverse modeling is quantified the authors find that predictability of caribbean sea and north tropical atlantic sea surface temperature anomalies sstas is enhanced when one uses global tropical sstas as predictors compared with using only tropical atlantic predictors this predictability advantage does not carry over into the equatorial and south tropical atlantic indeed persistence is a competitive predictor in those regions to help resolve the issue of whether or not the dipole structure found by applying empirical orthogonal function analysis to tropical atlantic ssts is an artifact of the technique or a physically real structure the authors combine empirically derived normal modes and their adjoints to form influence functions maps highlighting the geographical areas to which the north tropical atlantic and the south tropical atlantic ssts are most sensitive at specified lead times when the analysis is confined to the atlantic basin the 6 month influence functions in the north and south tropical atlantic tend to be of the opposite sign and evolve into clear dipoles within 6 months when the analysis is performed on global tropical ssts the 6 month influence functions are connected

soft linkage transfer zones insights from the northern eastern desert egypt abstract several soft linkage transfer zones are well exposed and defined at the northern eastern desert egypt they are outcropped in the form of folds that soft linking the overlapped ends of normal faults these folds have several shapes and extensions which are easily pictured on satellite imagery detailed surface geological field mapping is carried out at gebel um raqm to assess geometries and origins of these folds three main categories of soft linkage folds are suggested in the present study these are 1 single fold soft linkage s sl 2 anticline syncline pair soft linkage p sl and 3 multiple folds soft linkage m sl structural analysis revealed that these folds represent relay ramps that encountered ductile deformation due to drag or reverse drag along the nearby planar or non planar normal fault planes respectively the formation of the categorized folds is controlled mainly by dip polarity geometry and overlapping overstepping of the overlapped normal faults in addition to mechanical stratigraphy and original dips of tilted beds the findings of this research are attractive for the analysis of similar soft linking folds at the subsurface and other outcrops worldwide as such folds have great significance in petroleum exploration

rift brittle deformation of se brazilian continental margin kinematic analysis of onshore structures relative to the transfer and accommodation zones of southern campos basin abstract high resolution drone supported mapping and traditional field work were used to refine the hierarchy and kinematics of rift related faults in the basement rocks and early cretaceous mafic dikes onshore of the campos basin se brazil two sets of structures were identified the most significant fault set is ne sw oriented with predominantly normal displacement at mesoscale this fault set is arranged in a rhombic pattern interpreted here as a breached relay ramp system the rhombic pattern is a penetrative fabric from the thin section to regional scale the second order set of structures is an e w ese wnw system of normal faults with sinistral component these e w structures are oriented parallel with regional intrabasinal transfer zones associated with the earliest stages of campos basin s rift system the crosscutting relationship between the two fault sets and tholeiitic dikes implies that the ne sw fault set is the older feature but remained active until the final stages of rifting in this region as the second order fault set is older than the tholeiitic dikes paleostresses estimated from fault slip inversion method indicated that extension was originally nw se with formation of the e w transfer followed by ese wnw oblique opening associated with a relay ramp system and related accommodation zones

a mid twentieth century reduction in tropical upwelling inferred from coralline trace element proxies abstract the cariaco basin is an important archive of past climate variability given its response to inter and extratropical climate forcing and the accumulation of annually laminated sediments within an anoxic water column this study presents high resolution surface coral trace element records montastrea annularis and siderastrea siderea from isla tortuga venezuela located within the upwelling center of this region a two fold reduction in cd ca ratios 3 5 1 7 nmol mol is observed from 1946 to 1952 with no concurrent shift in ba ca ratios this reduction agrees with the hydrographic distribution of dissolved cadmium and barium and their expected response to upwelling significant anthropogenic variability is also observed from pb ca analysis observing three lead maxima since 1920 kinetic control of trace element ratios is inferred from an interspecies comparison of cd ca and ba ca ratios consistent with the sr ca kinetic artifact but these artifacts are smaller than the environmental signal and do not explain the cd ca transition the trace element records agree with historical climate data and differ from sedimentary faunal abundance records suggesting a linear response to north atlantic extratropical forcing cannot account for the observed historical variability in this region

variability of the atlantic meridional mode during the atlantic hurricane season abstract an observational and modeling study is conducted to investigate the structure of the atlantic meridional mode amm during the atlantic hurricane season and the relationship between amm related sst anomalies and environmental conditions that influence seasonal tropical cyclone activity the observational analysis shows that during the atlantic hurricane season the amm exhibits a similar sst and low level wind structure as during boreal spring when the amm is most active observed amm sst variations are accompanied by air temperature and moisture anomalies that are limited to the boundary layer and an anomalous baroclinic circulation structure in the northern subtropical atlantic with an anomalous lower level cyclonic circulation residing under an anomalous upper level anticyclone during a warm phase this baroclinic structure contributes to a reduction in vertical wind shear over the tropical atlantic that is dominated by changes in the upper level flow two sets of model experiments were cond

extratropical influences on the inter annual variability of south asian monsoon the effects of extratropical dynamics on the interannual variations in south asian monsoon sam are examined based on ncep ncar reanalysis and cru precipitation data a conditional maximum covariance analysis is performed on sea level pressure 200 hpa geopotential heights and the sam rainfall by removing the linear effects of el nino southern oscillation from the fields it is found that two modes provide a strong connection between the upper level circulation in the atlantic european region and sam rainfall the circumglobal teleconnection cgt and the summer north atlantic oscillation snao the structures in the 200 hpa heights of both modes in the atlantic region are similar in the atlantic region and their southeastward extension to south asia sa also corresponds to upper level ridges in their positive phases in slightly different positions nevertheless the influence of both modes on sam rainfall is distinct whereas a positive cgt is related to a widespread increase of rainfall in sam a positive snao is related to a precipitation dipole with its positive phase over pakistan and the negative phase over northern india the physical mechanisms for the influence of cgt and snao on sam are related to the upper level geopotential anomaly which affects the amplitude and position of the low level convergence the small displacements of the centers of these responses and the low level cold advection from the north east of sa in case of snao explain the differences in the corresponding sam rainfall distributions these findings are confirmed with the relatively high resolution coupled climate model ec earth which gives confidence in the physical basis and robustness of these extratropical variability modes and their influence on the south asian monsoon rainfall

fault propagation folding in extensional settings examples of structural style and synrift sedimentary response from the suez rift sinai egypt field data from the oligocene miocene gulf of suez rift demonstrate that coeval growth faults folds and transfer zones exerted a major control on synrift stratigraphic sequence development growth folds in the suez rift are related to steeply dipping normal faults that propagated upward resulting in broad upward widening monoclines in overlying strata folding during fault propagation was accommodated by layer parallel slip and detachment along mudstone horizons as well as by normal and rare reverse secondary faults that propagated away from the master fault the eventual propagation of the master fault through to the surface left the steep limb of the monocline and most of the secondary faults in the hanging wall this evolving structural style exerted a marked control on the geometry and stacking patterns of coeval synrift sediments synrift sediments display onlap and intraformational unconformities toward the growth monoclines and buried faults whereas they diverge into broadly synclinal expanded sections away from the growth monocline continued movement across buried faults resulted in the progressive rotation of the monoclinal limb and associated synrift sediments each successively younger sequence dipping basinward at a shallower angle than the previous one the resulting synrift geometries differ significantly from stratal geometries normally anticipated adjacent to normal faults along strike variations in facies stacking patterns are also commonly associated with decreasing displacement across faults and associated folds toward low relief transfer zones data from other rift basins indicate that fault propagation folds are not unique to the gulf of suez

rapid 20th century warming in the caribbean and impact of remote forcing on climate in the northern tropical atlantic as recorded in a guadeloupe coral we have generated 104 year long 1895 1999 monthly 18o and sr ca time series from a fast growing diploria strigosa coral core drilled off guadeloupe island lesser antilles coral sr ca reliably records interannual to decadal surface air temperature sat variations in the region and shows a pronounced warming of approximately 1 5 c since 1950 with the strongest warming 1 2 c occurring since 1975 this warming is also evident in sat measured at guadeloupe which ends in 1951 thus our sr ca series extends the air temperature record by 56 years we find that the past few decades are the warmest years over the entire period of record the accelerated warming since 1950 is accompanied by a pronounced decrease in regional precipitation this dampens the warming signal indicated by coral 18o which is too low only 0 7 0 8 c since 1951 consistently 18osw estimated from the coral proxies also shows a strong decrease since 1950 our data suggest an inverse relationship between sat and precipitation i e warmer and drier for the latter half of the 20th century with the strongest trends since the mid 1970s this is consistent with recent observational and model data which report that while over the tropical oceans rainfall has increased due to an increase in sea surface temperatures precipitation over land regions is reduced a continuation of this warming and drying trend over caribbean land regions would have severe societal consequences especially in the context of anthropogenic warming the el nino southern oscillation enso and the north atlantic oscillation nao are the two major climate modes affecting large scale sst variability in the northern tropical atlantic both sr ca and 18o show a close relationship to enso and the nao a quantitative comparison between extremes in mean march may coral 18o and the nino3 and nao indices imply that climate variability in the northern tropical atlantic is mainly forced by tropical pacific and north atlantic variability spectral analysis suggests that the relative importance of enso and the nao is frequency dependent with enso dominating at interannual and the nao dominating at interdecadal time scales

regionalization and spatial properties of ceara state rainfall in northeast brazil the overall daily rainfall pattern of ceara for 19 years 1974 1992 was analyzed in terms of physiography and atmospheric circulation this information was used to suggest a regionalization of the state s rainfall into homogeneous areas the three large scale precipitation mechanisms intertropical convergence zone cold fronts and upper air vortices interact and create a certain rainfall pattern over the state during different months an example of this interaction is the opposite behavior that the northern and southern parts of the state tend to have when considering the amount of precipitation during the rainy season that is in general large amounts of rain in the southern part of the state tend to be associated with small amounts of rain in the northern part and vice versa as influenced by the opposite influence of the cold fronts and the upper air vortices at the same time the orographical influence enhances the precipitation in the northern part of the state and decreases precipitation in the central part of the state the state could be divided into six homogeneous precipitation regions 1 the northwestern part of the state locally influenced by the mountain massif of serra da ibiapaba 2 3 the northern and northeastern ceara influenced locally by sea breeze and the slopes of the serra de baturite 4 5 the central state influenced by the chapada do apodi and the serra de uruburetama and 6 the southern part of the state influenced mostly by cold fronts and by the slopes of the serra do araripe less

uav and sfm in detailed geomorphological mapping of granite tors an example of starościnskie skaly sudetes sw poland the paper presents an example of using photographs taken by unmanned aerial vehicles uav and processed using the structure from motion sfm procedure in a geomorphological study of rock relief subject to analysis is a small rock city in the west sudetes sw poland known as staro cinskie skaly and developed in coarse granite bedrock the aims of this paper were first to compare uav sfm derived data with the cartographical image based on the traditional geomorphological field mapping methods and the digital elevation model derived from airborne laser scanning als second to test if the proposed combination of uav and sfm methods may be helpful in recognizing the detailed structure of granite tors as a result of conducted uav flights and digital image post processing in agisoft software it was possible to obtain datasets dense point cloud texture model orthophotomap bare ground type digital terrain model dtm which allowed to visualize in detail the surface of the study area in consequence it was possible to distinguish even the very small forms of rock surface microrelief joints aplite veins rills and karren weathering pits etc otherwise difficult to map and measure the study includes also valorization of particular datasets concerning microtopography and allows to discuss indisputable advantages of using the uav sfm based dtm in geomorphic studies of tors and rock cities even those located within forest as in the presented case study

the impacts of inter el nino variability on the tropical atlantic and northeast brazil climate abstractin this study observations and numerical simulations are used to investigate how different el nino events affect the development of sst anomalies in the atlantic and how this relates to the brazilian northeast ne precipitation the results show that different types of el nino have different impacts on the sst anomalies of the equatorial and tropical south atlantic but a similar sst response in the tropical north atlantic strong and long weak and short el ninos with the main heating source located in the eastern central pacific generate cold warm anomalies in the cold tongue and benguela upwelling regions during boreal winter and spring when the sst anomalies in the eastern equatorial and tropical south atlantic are cold warm the meridional sst gradient across the equator is positive negative and the itcz is not allowed allowed to move southward during the boreal spring as a consequence the precipitation is below above the average over the ne thus strong and long weak and s

a new perspective for the directivity of rock quality designation rqd and an anisotropy index of jointing degree for rock masses abstract the rock quality designation rqd index is defined as the percentage of the borehole core or scanline that consists of intact lengths 0 1 m and has been widely used as an engineering measure of the jointing degree of a rock mass the directivity of rqd which means the value of the rqd obtained from drilling cores or scanlines with different orientations can be different for a given site is usually regarded as a drawback by researchers and engineers this study presents a new perspective for the directivity of rqd the directivity of rqd should be regarded as an advantage of the index because it essentially reflects the anisotropy of rock masses because a smaller value of the rqd index implies a better reproduction of the different jointing degrees of different rock masses its minimum value is selected as the representative rqd rqdr and its corresponding direction is called as the representative direction of rqd in this study to obtain the rqdr and its representative direction theoretical formulas are derived to calculate the rqd in any direction based on some known rqds in different directions the proposed formulas consider the variance of the discontinuity orientations and sizes for a discontinuity set use the traditional concept of rqd and possess the associated simplicity they only require sampling a few additional discontinuity orientations therefore the proposed approach is easy to understand and apply in engineering practices an anisotropy index of jointing degree aijd is defined to quantitatively describe the anisotropy of jointing degree for rock masses the range of aijd is from 0 to 100 and the larger value of aijd reflects stronger anisotropy of jointing degree of a rock mass in this study a hypothetical three dimensional discontinuity network is constructed by performing monte carlo simulations based on which the generated data are analyzed to validate the proposed method the comparison between the calculated and actual values of the rqd shows that a the difference between the calculated and actual values of the rqd is 86 0 of the 1368 scanlines examined with respect to 12 scanline groups except sg4 1 group for which the proportion is 66 2 b the difference between the calculated and actual values of the rqd is 96 2 of the 1368 scanlines examined with respect to 12 scanline groups except sg4 1 for which the proportion is 86 7 and c the proposed method of calculating the rqd in any direction based on some known rqds in different directions is satisfactory in addition the comparisons show that the calculated rqdr and representative direction exhibit a good agreement with the actual results and hence the proposed method for this purpose is satisfactory moreover an actual rock mass of a slope around the qingshan lake national forest park in china is investigated and the results show that the proposed method is valid for that rock mass

uav based detection and spatial analyses of periglacial landforms on demay point king george island south shetland islands antarctica abstract high resolution aerial images allow detailed analyses of periglacial landforms which is of particular importance in light of climate change and resulting changes in active layer thickness the aim of this study is to show possibilities of using uav based photography to perform spatial analysis of periglacial landforms on the demay point peninsula king george island and hence to supplement previous geomorphological studies of the south shetland islands photogrammetric flights were performed using a pw zoom fixed winged unmanned aircraft vehicle digital elevation models dem and maps of slope and contour lines were prepared in esri arcgis 10 3 with the spatial analyst extension and three dimensional visualizations in esri arcscene 10 3 software careful interpretation of orthophoto and dem allowed us to vectorize polygons of landforms such as i solifluction landforms solifluction sheets tongues and lobes ii scarps taluses and a protalus rampart iii patterned ground hummocks sorted circles stripes nets and labyrinths and nonsorted nets and stripes iv coastal landforms cliffs and beaches v landslides and mud flows and vi stone fields and bedrock outcrops we conclude that geomorphological studies based on commonly accessible aerial and satellite images can underestimate the spatial extent of periglacial landforms and result in incomplete inventories the pw zoom uav is well suited to gather detailed geomorphological data and can be used in spatial analysis of periglacial landforms in the western antarctic peninsula region

eulerian and lagrangian correlation structures of convective rainstorms the eulerian and lagrangian correlation structures of 13 convective rainstorms were investigated using rainfall data from the 1987 convective initiation downburst experiment in denver colorado one minute rainfall data were available for two superposed raingage networks 46 raingages on the portable automated mesonet pam network at a mean spacing of 10 6 km and 31 additional raingages on the federal aviation administration lincoln laboratory operational weather studies flows network at a mean spacing of 2 4 km eulerian correlation coefficients are low and often negative for high resolution 1 min rainfall data correlation increases with time averaging beyond 10 15 min for single rain cells on the flows network and small mesoscale rainstorms on the pam network the average speed of rain cells and small mesoscale rainstorms was found to be 76 5 and 56 4 km hr 1 respectively storm kinematic is identified as the cause of data scatter and low eulerian correlations convective rainstorms are essentially uncorrelated in the eulerian reference frame at a typical raingage spacing of 2 3 km for rain cells and 10 15 km for small mesoscale rainstorms a spatial cross correlation analysis in a lagrangian reference frame moving with the center of mass of the storm separates the kinematic component from the structural component of a rainfall field the spatial cross correlations in the lagrangian rainfall field show considerable improvement over the eulerian spatial correlation plots and data scatter is greatly reduced the increase in correlation coefficients from eulerian to lagrangian reference frames typically ranged from 0 5 to 1 1

an integrative approach for preliminary environmental engineering investigations amidst reclaiming desert land a case study at east nile delta egypt scientific interest within the desert lands lies on mapping the near surface clayey soils being made environmental engineering problems e g water logging and cracked pavements as a starting point used for urban rational development boreholes direct current resistivity dcr soundings and electrical resistivity tomography surveys and preliminary geotechnical studies are employed in an integrative approach for mapping and characterizing the foundation soil this study is carried out at one of the main urban reclamation projects amidst desert fringes of east nile delta egypt as a case study where the in situ soil properties are variable even within a short distance and consequently difficult to be predicted conventional and non conventional inversion approaches are applied for solving the inverse problems of dcr data the results are calibrated with the drilled borehole lithology two main geoelectrical resistivity layers are distinguished the upper medium to high resistivity soils corresponding to surface poorly graded sand with gravels underlain by low resistivity layer attributing to clayey sand with calcareous materials the inversion results show the sequential joint use efficiency of the two approaches in mapping the near surface layer boundaries providing realistic soil heterogeneities tomography in respect of such results and from an engineering point of view the exaggerated clayey soils are highly saturated in some places representing 1 medium plasticity moderate to high swelling and 2 low compressive strength it is conceivable that such soils can exhibit geotechnical problems especially under wetting conditions consequently the integrative approach is cost effective and opens the way for engineers on where prioritized interventions are required to the urban expansion

surface and borehole geophysics for the rehabilitation of a concrete dam penne central italy abstract in this paper surface and borehole geophysical surveys are employed to improve the effectiveness of a rehabilitation intervention cut off wall to be executed on the right abutment of a leaking concrete dam penne central italy in a first step surface geophysical measurements electrical resistivity and p wave velocity data were collected to provide a geophysical model to be compared to the preliminary geological model available before the geophysical survey because significant differences emerged between the geophysical and the preliminary geological models a second phase of borehole investigations was planned to validate the geophysical reconstruction obtained from surface data the final geological model resulting from the geophysical results differs significantly from the preliminary model available at the time of the geophysical survey therefore the planned cut off wall needs to be extended both laterally and in depth beyond the position estimated before the geophysical campaign so that the low permeability bedrock is intercepted at a depth equal or lower than the critical one at the end the low cost geophysical campaign 1 5 of the entire costs of the intervention was highly beneficial to this project minimizing subsurface geological uncertainty to design an effective anti seepage intervention and stressing the importance of a representative geological model for engineering design

some eulerian and lagrangian statistical properties of rainfall at small space time scales abstract management of urban hydrological systems requires a knowledge of short term and small scale rainfall properties small catchment areas dense building structures a high degree of impermeable areas and resulting rapid runoff mean that the properties of individual rain cells are important considerations accordingly this paper characterizes mainly spatial rainfall properties on a scale suitable for urban hydrology because of the usually dominant advective velocity component of individual rain cells the eulerian view observations of the moving rain cell by a fixed rain gage network gives a distorted picture in the direction of movement of the actual rain cell the extent of distortion depends on the magnitude of the advective velocity the lagrangian approach moving along with the same speed and direction as the cell gives different information regarding cell characteristics e g size compared with the eulerian approach it is shown that the lagrangian cell size as indicated by the spatial correlation structure on average is twice the size of the eulerian cell size thus it is argued that the lagrangian approach provides a more realistic picture of the rainfall structures compared with the eulerian approach the cell properties exhibit a temporal persistence of the spatial characteristics in the direction of movement this persistence is however not strong and thus a forecasting procedure using advection only does not seem appropriate

automated 1d interpretation of resistivity soundings by simultaneous use of the direct and iterative methods noise contamination of measured data greatly affects the final results of inversion three types of noise source random and systematic errors and the uncertainties due to the inadequacy of the mathematical model in representing the actual physical conditions are discussed in the framework of resistivity sounding data two methods are proposed for describing these uncertainties the first possibility is to smooth the measured data by a combination of simple fitting functions that satisfies the 1d smoothness criteria and consequently simulates the behaviour of a 1d schlumberger apparent resistivity curve the second method is to derive weight coefficients from the differences between the measured and the smoothed data sets both methods are carried out under the control of the interpreter the relative merits and drawbacks of the direct and iterative interpretation methods used for the estimation of the parameters of the layered earth model are summarized two variants of the combination of these methods are presented to obtain more powerful and automatic interpretation schemes in the sequential interpretation an initial guess supplied by the direct method is improved by the iterative method to obtain a reasonable fit between the measured data and the model response in the simultaneous interpretation the successive application of the direct and iterative methods is carried out starting from the first branch of the apparent resistivity curve the operation is then shifted to subsequent branches that represent the deeper parts of the geoelectric section this is similar to the data acquisition applied in direct current sounding in which the depth penetration is increased by expanding the current electrode spacings the proposed sequential and simultaneous interpretation algorithms require minimum aids and efforts of the interpreter

karst landforms revealed at various scales using lidar and uav in semi arid brazil consideration on karstification processes and methodological constraints abstract this paper analyzes different types of karst landforms and their relationships with fracture systems sedimentary bedding and fluvial processes we mapped karst features in the cretaceous carbonates of the jandaira formation in the potiguar basin brazil we used high resolution digital elevation models acquired using lidar and aerial orthophotographs acquired using an unmanned aerial vehicle uav we grouped and described karst evolution according to scale and degree of karstification these degrees of karst evolution are coeval fractures are opened by dissolution forming vertical fluid conduits whereas coeval dissolution occurs along horizontal layers this conduit system acts as pathways for water flow the enlargement of conduits contributes to the collapse of blocks in sinkholes and expansion of caves during an intermediate degree of karstification propagation of dissolution can cause the coalescence of sinkholes and the capture of small streams fluvial processes dominate karst dissolution at an advanced degree of karstification comparisons with previously published ground penetrating radar gpr borehole and seismic surveys in sedimentary basins indicate that these structures can be partially preserved during burial

evolution of the lorenz energy cycle in the intertropical convergence zone in the south american sector of the atlantic ocean abstractthe intertropical convergence zone itcz in the south american sector of the atlantic ocean is identified using outgoing longwave radiation olr data in order to investigate the evolution of the lorenz energy cycle in the region dominated by this large scale feature the ncep reanalysis data are utilized to calculate the zonal and eddy components denoted by z and e respectively of kinetic energy k and available potential energy a i e kz ke az and ae and their conversions on a daily basis a wavelet decomposition of the time series is performed to detect long term cycles trends in the atlantic itcz region this work also investigates trends in sea surface temperature sst and sea level pressure slp in the itcz region and connections between the itcz and the southern oscillation index soi a strong annual cycle in all the energy components with high peaks in austral summer is observed approximately 91 of the zonal component of energy is contained on decadal or longer time scales

on the dynamics of droughts in northeast brazil observations theory and numerical experiments with a general circulation model abstract it is proposed that a possible mechanism for the occurrence of severe droughts over northeast brazil is the establishment of a thermally direct local circulation which has its ascending branch at about 10 n and its descending branch over northeast brazil and the adjoining oceanic region the driving for this anomalous circulation is provided by warming due to enhanced moist convection associated with warmer sea surface temperature anomalies over the northern tropical atlantic and cooling associated with colder sea surface temperature anomalies in the southern tropical atlantic the combined effects of thermally forced subsidence and reduced evaporation and moisture flux convergence produces severe drought conditions over northeast brazil we have examined the monthly mean sea surface temperature anomalies over the tropical atlantic and rainfall anomalies over two selected stations fortaleza 3 46 s 38 31 w and quixeramobim 5 12 s 39 18 w for 25 years 1948 72 it is found that the most sever

temporal variability in spatial correlation of daily rainfall composite correlation fields based on a 5 year record of daily rainfall at 67 stations throughout tunisia were used to investigate spatial and temporal properties of rainfall fields the composite correlation fields had in general banded or elliptical patterns and with the elongations generally along the coastline or the topographical ridges the banded patterns occurred usually during the rainy season and the elliptical patterns occurred toward the summer or early autumn the ratio of width to length of the elongated correlation fields varied in general between 0 1 and 0 4 the composite correlation fields defined as the area within the 0 7 correlation isoline were usually less than about 8 000 km2 the mean monthly rainfall was moderately correlated with the size of the composite correlation fields the major orientation of the coastline seems to be a more important factor for the rainfall generation than are local irregularities in the coastal orientation and local topographical differences

uav based remote sensing of the super sauze landslide evaluation and results unmanned aerial vehicles uavs equipped with digital compact cameras can be used to map landslides quickly and at a high ground resolution images taken by a radio controlled mini quad rotor uav of the super sauze france landslide have been used to produce a high resolution ortho mosaic of the entire landslide and digital terrain models dtms of several regions the uav capability for imaging fissures and displacements on the landslide surface has been evaluated and the subsequent image processing approaches for suitably georectifying the data have been assessed for super sauze horizontal displacements of 7 to 55 m between a high resolution airborne ortho photo of may 2007 and a uav based ortho mosaic of october 2008 have been measured fixed areas of persistent deformation have been identified producing fissures of different distributions and orientations comparable to glacial crevasses and relating directly to the bedrock topography the uav has demonstrated its capability for producing valuable landslide data but improvements are required to reduce data processing time for the efficient generation of ortho mosaics based on photogrammetric dtms in order to minimise georeferencing errors

internal structural architecture of a soft linkage transfer zone using outcrop and dc resistivity data implications for preliminary engineering assessment abstract the current study presents a new integrative approach for detailed structural mapping of a soft linkage transfer zone using outcrop boreholes and dcr data in the form of soundings and 2d electrical resistivity tomography 2d ert as a case study the present approach is implied for studying the geo engineering conditions of a highly deformed desert land entry to reclaim at cairo suez district egypt the approach has led to the spatial understanding of the subsurface heterogeneity and complex structures at a level of accuracy unattainable with traditional surface structural mapping alone for preliminary geotechnical assessment some physical and geotechnical properties are characterized by field and laboratory measurements for collected soil samples moreover the inverted dcr data are used to predict the rqd values using a polynomial relationship between rqd and the intrinsic resistivity notably the calculated and actual values of rqd are in general in the same order considering the error factor value and hence the derived equation for rqd prediction is satisfactory therefore the proposed approach reduces the uncertainty of the constructed structural model for engineering design in addition merging outcrop with dcr data allows us with a limited frame of time to partially mitigate disasters to civilization by better i potential location understanding and ii remediation plans tuning for a complex structured site

debris flow dominance of alluvial fans masked by runoff reworking and weathering arid alluvial fan aggradation is highly episodic and fans often comprise active and inactive sectors hence the morphology and texture of fan surfaces are partly determined by secondary processes of weathering and erosion in addition to primary processes of aggradation this introduces considerable uncertainty in the identification of formative processes of terrestrial and martian fans from aerial and satellite imagery the objectives of this study are i to develop a model to describe the sedimentological and morphological evolution of inactive fan surfaces in arid settings and ii to assess the relative importance of primary processes of aggradation and secondary processes of weathering and reworking for surface morphology and sedimentology and for the stratigraphic record we studied an alluvial fan characterized by a recently active sector and a long abandoned inactive sector along the coast of the hyperarid atacama desert here rates of primary geomorphic activity are exceptionally low because of extreme aridity while weathering rates are relatively high because of the effects of coastal fogs long term processes of fan aggradation and reworking were determined through sedimentological facies analysis of stratigraphic sections ground surveys for textural and morphological patterns at the fan surface were integrated with remote sensing by an unmanned airborne vehicle uav discharges and sediment transport capacities were calculated to estimate the efficiency of secondary runoff in reshaping the inactive fan sector stratigraphic sections reveal that the fan was dominantly aggraded by debris flows whereas surface morphology is dominated by debris flow signatures in the active sector and by weathering and runoff on the inactive sector on the latter rapid particle breakdown prevents the formation of a coarse desert pavement furthermore relatively frequent local runoff events erode proximal debris flow channels on the inactive sector to form local lag deposits and accumulate fine sediment in low gradient distal channels forming a well developed drainage pattern that would suggest a runoff origin from aerial images nevertheless reworking is very superficial and barely preserved in the stratigraphic record this implies that fans on earth and mars that formed dominantly by sporadic mass flows may be masked by a surface morphology related to other processes

multimodel study of tropical atlantic variability and change 1 interannual variability associated with the zonal and the meridional mode in the tropical atlantic is studied in nine coupled ocean atmosphere models for twentieth century climate conditions tc and the sres a1b scenario for future greenhouse gas concentrations for tc the subtropical part of the meridional mode is reasonably well simulated in contrast to the deep tropical part of the meridional mode and the zonal mode a common model bias is that the onset of the meridional mode is preceded by the presence of a zonal mode in boreal fall that extends towards the western boundary of the atlantic basin and which initiates a wind evaporation sst feedback as a result of this there is a spuriously strong interaction between the zonal and the meridional mode the models that seem to best represent the meridional mode show a weakening for future climate conditions biases in the zonal mode are too strong to assess changes citation breugem w p w hazeleger and r j haarsma 2006 multimodel study of tropical atlantic variability and change geophys res lett 33 l23706 doi 10 1029 2006gl027831

identification and calibration of spatial correlation patterns of rainfall abstract the significance of spatial distribution of rainfall and its effects on spatial correlation functions are reviewed a number of statistical terms and properties are explained in depth with reference to the theory of variograms originally adopted in geostatistics this is followed by a detailed analysis of theoretical variogram models effects of meteorological orographic and space time aggregation scales and a discussion on network design areal mean calculations and storm velocities empirical variogram and validation techniques are then examined some applications to two different parts of lombardia the mountainous valtellina catchment and a large part of the flat area of the region in northern italy are given with a discussion of the results in the appendix the technique of kriging is explained with reference to the estimation of the spatial distribution of the random rainfall field

the influence of amazon rainfall on the atlantic itcz through convectively coupled kelvin waves abstract using outgoing longwave radiation olr and tropical rainfall measuring mission trmm daily rain rate data systematic changes in intensity and location of the atlantic intertropical convergence zone itcz were detected along the equator during boreal spring it is found that the changes in convection over the tropical atlantic may be induced by deep convection in equatorial south america lagged regression analyses demonstrate that the anomalies of convection developed over the land propagate eastward across the atlantic and then into africa the eastward propagating disturbances appear to be convectively coupled kelvin waves with a period of 6 7 5 days and a phase speed of around 15 m s 1 these waves modulate the intensity and location of the convection in the tropical atlantic and result in a zonal variation of the atlantic itcz on synoptic time scales the convectively coupled kelvin wave has substantial signals in both the lower and upper troposphere both a reanalysis dataset and the qui

advances in permafrost and periglacial research in antarctica a review recently the research on permafrost periglacial morphology and processes had a great stimulus especially from the international polar year permafrost areas of continental antarctica with its extreme dry and cold environment can be considered an analog of extraterrestrial landscapes like those on mars but also preserve much paleoclimatic information of this crucial part of the global climatic system on the other hand maritime antarctica is one of the areas of the world currently affected by the greatest air warming and provides a unique opportunity to understand the impacts of climate change on permafrost and its related ecosystems despite the significant recent progress some gaps on permafrost distribution still remain as the network for permafrost and active layer monitoring needs further enlargement and better standardization ground ice its age and stability over time need further investigation as well as the role of living organisms on the weathering processes within the cryotic rocks the landscape evolution of continental antartica could be improved providing potential implications also for a better understanding and modeling of life and landscape evolution of other planets

periglacial processes and landforms in the south shetland islands northern antarctic peninsula region abstract periglacial processes and landforms together with the presence of permafrost are among the most relevant geomorphological elements in the northern antarctic peninsula region their distribution affects the hydrology and has consequences for the ecosystems of the ice free areas in this paper a compilation of the different types of periglacial landforms and processes occurring in the south shetland islands is carried out and their spatial distribution is analysed furthermore the relationships of the periglacial landforms with local conditions and permafrost distribution have been taken into account a total of thirty three types of periglacial landforms were identified and considered in this work patterned ground and stone fields are the most common periglacial landforms which are located within a wide altitudinal range and mainly on platforms field studies aerial photograph and satellite imagery interpretation were implemented to produce detailed maps from ten areas with different geological geomorphological and relief characteristics including the largest and most relevant ice free areas within the archipelago showing the presence and spatial distribution of periglacial landforms this work shows that the periglacial environment primarily conditioned by the regional climatic conditions has a great diversity in the studied region and that the distribution of the periglacial landforms is also related to local relief and geomorphological characteristics lithology hydrogeology and presence of permafrost where altitude plays an important role periglacial phenomena are widespread above 10 m a s l and are especially active on slopes and platforms between 30 and 100 m a s l the spatial distribution of periglacial landforms helps to identify the presence of permafrost that is dominant above 25 30 m a s l and more than 70 of the surface is occupied by active layer related landforms