dwindling groundwater resources in northern india from satellite gravity observations 1 northern india and its surroundings home to roughly 600 million people is probably the most heavily irrigated region in the world temporal changes in earth s gravity field in this region as recorded by the grace satellite mission reveal a steady large scale mass loss that we attribute to excessive extraction of groundwater combining the grace data with hydrological models to remove natural variability we conclude the region lost groundwater at a rate of 54 9 km3 yr between april 2002 the start of the grace mission and june 2008 this is probably the largest rate of groundwater loss in any comparable sized region on earth its likely contribution to sea level rise is roughly equivalent to that from melting alaskan glaciers this trend if sustained will lead to a major water crisis in this region when this non renewable resource is exhausted

post processing removal of correlated errors in grace data 1 gravity fields produced by the gravity recovery and climate experiment grace satellite mission require smoothing to reduce the effects of errors present in short wavelength components as the smoothing radius decreases these errors manifest themselves in maps of surface mass variability as long linear features generally oriented north to south i e stripes the presence of stripes implies correlations in the gravity field coefficients here we examine the spectral signature of these correlated errors and present a method to remove them finally we apply the filter to a model of surface mass variability to show that the filter has relatively little degradation of the underlying geophysical signals we seek to recover

succession of arboreal taxa during the late glacial in south eastern poland climatic implications abstract this paper presents and discusses vegetation changes between ca 14 910 and 11 620 cal bp which are recorded in the deposits of a small mire located in south eastern poland particular attention is paid to arboreal taxa changes in arboreal vegetation are reconstructed on the basis of pollen analysis including pollen accumulation rate par and analysis of plant macrofossils these being supported by radiocarbon chronology before the onset of the gi 1 warming 14 910 310 14 810 280 cal bp a mosaic of pinus and betula wood patches and or isolated stands of trees along with heliophilous juniperus thickets were dispersed within patches of herb steppe and tundra communities thermal amelioration at the gs 2 gi 1 transition ca 14 810 280 14 510 200 cal bp led to the spread of salix and to a lesser extent of tree birches betula pines pinus and hippophae rhamnoides in the light of par values from ca 14 550 210 cal bp there were open pine birch woodlands there which ca 14 270 160 cal bp turned into dense forests cold oscillations such as gi 1d gi 1c2 and gi 1b dated in the profile at ca 14 190 120 13 870 140 13 740 120 13 490 80 and 13 120 12 870 60 cal bp respectively are visible as declines in the par of arboreal taxa from ca 13 770 120 cal bp picea abies whose nearest glacial refugia were located in the western carpathians probably reached the site surroundings 50 n in the younger dryas gs 1 climate deterioration caused a decline in birch population in the first phase a slight retreat of forests and the simultaneous expansion of artemisia poaceae steppe communities and juniperus thickets the par values reflect a division of the younger dryas into two distinct phases an older phase more severe for tree populations probably due to longer and cooler winters and a younger phase with milder winters which begun ca 11 960 110 cal bp

geomorphic response detection and quantification in a steep forested torrent abstract extreme events such as flash floods and debris flows are frequent phenomena that occur in steep torrential catchments these kinds of events can cause notable geomorphic changes repeated terrestrial laser scanning tls surveys were performed in a steep forested catchment of the kuzlovec torrent drainage area 0 7 km2 in central slovenia where a 200 m long section of the torrent was scanned in 2013 2014 and 2015 the main aim of this study was to perform the geomorphic response detection in the torrent due to hydro meteorological events of different magnitudes after applying several pre processing steps digital terrain models dtms with a cell resolution of 5 cm were produced the geomorphic change detection was performed using the dtm of difference approach dod several above average flow events occurred in the period from 2013 to 2015 some of them can be regarded as floods the 2014 august extreme flash flood that was initiated by the rainfall event with a return period exceeding 100 years where maximum 1 minute rainfall intensities were up to 288 mm h led to erosion rates of an order of magnitude higher than average annual erosion rates moreover the analysis of the geomorphic changes shows that the august 2014 flash flood caused intense sediment transport processes that resulted in the changes at the location of the main stream channel thalweg and reduced channel roughness the unit stream power for the scanned section of the torrent was assessed to be approximately 500 w m2 during this extreme event this is above the thresholds that were suggested to differentiate between the situations where significant geomorphic changes can occur and the situations where geomorphic changes are not notable

crustal dilatation observed by grace after the 2004 sumatra andaman earthquake we report the detection of an earthquake by a space based measurement the gravity recovery and climate experiment grace satellites observed a 15 microgalileo gravity change induced by the great december 2004 sumatra andaman earthquake coseismic deformation produces sudden changes in the gravity field by vertical displacement of earth s layered density structure and by changing the densities of the crust and mantle grace s sensitivity to the long spatial wavelength of gravity changes resulted in roughly equal contributions of vertical displacement and dilatation effects in the gravity measurements the grace observations provide evidence of crustal dilatation resulting from an undersea earthquake

recent glacier mass changes in the gulf of alaska region from grace mascon solutions the mass changes of the gulf of alaska goa glaciers are computed from the gravity recovery and climate experiment grace inter satellite range rate data for the period april 2003 september 2007 through the application of unique processing techniques and a surface mass concentration mascon parameterization the mass variations in the goa glacier regions have been estimated at high temporal 10 day and spatial 2 2 arc degrees resolution the mascon solutions are directly estimated from a reduction of the grace k band inter satellite range rate data and unlike previous grace solutions for the goa glaciers do not exhibit contamination by leakage from mass change occurring outside the region of interest the mascon solutions reveal considerable temporal and spatial variation within the goa glacier region with the largest negative mass balances observed in the st elias mountains including the yakutat and glacier bay regions the most rapid losses occurred during the 2004 melt season due to record temperatures in alaska during that year the total mass balance of the goa glacier region was 84 5 gt a 1 contributing 0 23 0 01 mm a 1 to global sea level rise from april 2003 through march 2007 highlighting the large seasonal and interannual variability of the goa glaciers the rate determined over the period april 2003 march 2006 is 102 5 gt a 1 which includes the anomalously high temperatures of 2004 and does not include the large 2007 winter balance year snowfall the mascon solutions agree well with regional patterns of glacier mass loss determined from aircraft altimetry and in situ measurements

grace measurements of mass variability in the earth system monthly gravity field estimates made by the twin gravity recovery and climate experiment grace satellites have a geoid height accuracy of 2 to 3 millimeters at a spatial resolution as small as 400 kilometers the annual cycle in the geoid variations up to 10 millimeters in some regions peaked predominantly in the spring and fall seasons geoid variations observed over south america that can be largely attributed to surface water and groundwater changes show a clear separation between the large amazon watershed and the smaller watersheds to the north such observations will help hydrologists to connect processes at traditional length scales tens of kilometers or less to those at regional and global scales

groundwater storage changes in the tibetan plateau and adjacent areas revealed from grace satellite gravity data abstract understanding groundwater storage gws changes is vital to the utilization and control of water resources in the tibetan plateau however well level observations are rare in this big area and reliable hydrology models including gws are not available we use hydro geodesy to quantitate gws changes in the tibetan plateau and surroundings from 2003 to 2009 using a combined analysis of satellite gravity and satellite altimetry data hydrology models as well as a model of glacial isostatic adjustment gia release 5 grace gravity data are jointly used in a mascon fitting method to estimate the terrestrial water storage tws changes during the period from which the hydrology contributions and the gia effects are effectively deducted to give the estimates of gws changes for 12 selected regions of interest the hydrology contributions are carefully calculated from glaciers and lakes by icesat 1 satellite altimetry data permafrost degradation by an active layer depth ald model soil moisture and snow water equivalent by multiple hydrology models and the gia effects are calculated with the new ice 6g c vm5a model taking into account the measurement errors and the variability of the models the uncertainties are rigorously estimated for the tws changes the hydrology contributions including gws changes and the gia effect for the first time we show explicitly separated gws changes in the tibetan plateau and adjacent areas except for those to the south of the himalayas we find increasing trend rates for eight basins 2 46 2 24 gt yr for the jinsha river basin 1 77 2 09 gt yr for the nujiang lancangjiang rivers source region 1 86 1 69 gt yr for the yangtze river source region 1 14 1 39 gt yr for the yellow river source region 1 52 0 95 gt yr for the qaidam basin 1 66 1 52 gt yr for the central qiangtang nature reserve 5 37 2 17 gt yr for the upper indus basin and 2 77 0 99 gt yr for the aksu river basin all these increasing trends are most likely caused by increased runoff recharges from melt water and or precipitation in the surroundings we also find that the administrative actions such as the chinese ecological protection and construction project help to store more groundwater in the three rivers source region and suggest that seepages from the endorheic basin to the west of it are a possible source for gws increase in this region in addition our estimates for gws changes basically confirm previous results along afghanistan pakistan north india and bangladesh and clearly reflect the excessive use of groundwater our results will benefit the water resource management in the study area and are of particular significance for the ecological restoration in the tibetan plateau

multivariate indications between environment and ground water recharge in a sedimentary drainage basin in northwestern china abstract a paucity of studies on the interaction between environment and ground water recharge severely restricts the ability of people to assess future water resources under changing environment in this study an effort to explore the relationship between the arid environment and ground water recharge was carried out using multivariate statistical techniques in a sedimentary drainage basin the jungar in northwestern china hierarchical cluster analysis hca and principal components analysis pca were performed based on hydrogeochemical data to assess the ground water recharge and its governing factors observation of the hca and pca analytical results revealed a division of seven clusters c1 to c7 and three principal components pc1 to pc3 which explained 59 6 16 6 and 10 9 of the variance respectively and thus accounted for the majority of the total variance in the original dataset based on these q mode hca clusters and r mode pac scores dominant environmental processes influencing recharge regimes were identified i e geogenic geomorphoclimatic and anthropogenic which separated the recharge regimes into four zones zone i to zone iv zones i and ii c4 c1 were associated to elevated hydroclimate degree coupled to low salinity zone iii c2 c3 was associated to moderately elevated salinity and evidently elevated contamination but coupled to low hydroclimate degree zone iv c5 c6 c7 was associated mainly to elevated salinity coupled to low or inverse hydroclimate degree it revealed that the geogenic processes are more significant 60 than the geomorphoclimatic 17 and anthropogenic 11 processes as a result the overall recharge process is rather heterogeneous and is strongly environment dominated in the jungar drainage system compared with other watersheds in arid environment a distinctive feature of the jungar waters is that they are affected by a combination of natural and non natural events rather than following a steady and continuous geological evolution these will continue to influence the recharge regime of the jungar for a long time due to its steady tectonics and arid climate however changing rainfall but not snow is becoming the key factor driving changes in ground water resources in this drainage system as results of the decades of warming and humidification in northwestern china

time variable gravity observations of ice sheet mass balance precision and limitations of the grace satellite data time variable gravity data from the gravity recovery and climate experiment grace mission have been available since 2002 to estimate the mass balance of the greenland and antarctic ice sheets we analyze current progress and uncertainties in grace estimates of ice sheet mass balance we discuss the impacts of errors associated with spherical harmonic truncation spatial averaging temporal sampling and leakage from other time dependent signals e g glacial isostatic adjustment gia the largest sources of error for antarctica are the gia correction the omission of l 1 terms nontidal changes in ocean mass and measurement errors for greenland the errors come mostly from the uncertainty in the scaling factor using release 5 0 rl05 grace fields for january 2003 through november 2012 we find a mass change of 258 41 gt yr for greenland with an acceleration of 31 6 gt yr2 and a loss that migrated clockwise around the ice sheet margin to progressively affect the entire periphery for antarctica we report changes of 83 49 and 147 80 gt yr for two gia models with an acceleration of 12 9 gt yr2 and a dominance from the southeast pacific sector of west antarctica and the antarctic peninsula

strug landslide in w slovenia a complex multi process phenomenon abstract large rock slides frequently cause secondary unstable phenomena many such instability processes happened after december 2001 when the strug rockslide estimated at 95 000 m3 was triggered above the kosec village near kobarid in the julian alps w slovenia it was initiated at the contact between high permeable calcareous rocks cretaceous scaglia thrusted over nearly impermeable clastic rocks cretaceous flysch soon after the rockslide initiation a rock fall with a volume of 45 000 m3 was initiated within the rockslide the kinetic push of the rock fall caused the movement of a translational soil landslide with a volume of 180 000 m3 that partially slipped into the torrential ravine of the brusnik stream after a sudden drop of 15 m in december 2001 the rockslide average velocity exponentially slowed down to less than 10 m year till the end of 2002 and came to a practical stillstand in 2003 after the rainfall in spring 2002 small debris flows made of clayey gravels with a volume of up to 1000 m3 started to flow from the zone of accumulation of the rock fall over the soil landslide to and along the channel of the brusnik stream in 2002 more than 20 debris flow events were registered the statistical analysis of the measured local rainfall intensities showed that debris flows were initiated at daily rainfall reaching from 20 to 30 mm depending on the antecedent precipitation this value may be taken as a specific hydrologic threshold for this site because in 2003 no more debris flows were registered a conclusion was drawn that debris flow events were rainfall induced but governed on the same time by the availability of rock fall debris in its zone of accumulation

grace hydrological estimates for small basins evaluating processing approaches on the high plains aquifer usa the gravity recovery and climate experiment grace satellites provide observations of water storage variation at regional scales however when focusing on a region of interest limited spatial resolution and noise contamination can cause estimation bias and spatial leakage problems that are exacerbated as the region of interest approaches the grace resolution limit of a few hundred km reliable estimates of water storage variations in small basins require compromises between competing needs for noise suppression and spatial resolution the objective of this study was to quantitatively investigate processing methods and their impacts on bias leakage grace noise reduction and estimated total error allowing solution of the trade offs among the methods tested is a recently developed concentration algorithm called spatiospectral localization which optimizes the basin shape description taking into account limited spatial resolution this method is particularly suited to retrieval of basin scale water storage variations and is effective for small basins to increase confidence in derived methods water storage variations were calculated for both csr center for space research and grgs groupe de recherche de geodesie spatiale grace products which employ different processing strategies the processing techniques were tested on the intensively monitored high plains aquifer 450 000 km2 area where application of the appropriate optimal processing method allowed retrieval of water storage variations over a portion of the aquifer as small as 200 000 km2

improved methods for observing earth s time variable mass distribution with grace using spherical cap mascons we discuss several classes of improvements to gravity solutions from the gravity recovery and climate experiment grace mission these include both improvements in background geophysical models and orbital parameterization leading to the unconstrained spherical harmonic solution jpl rl05 and an alternate jpl rl05m mass concentration mascon solution benefitting from those same improvements but derived in surface spherical cap mascons the mascon basis functions allow for convenient application of a priori information derived from near global geophysical models to prevent striping in the solutions the resulting mass flux solutions are shown to suffer less from leakage errors than harmonic solutions and do not necessitate empirical filters to remove north south stripes lowering the dependence on using scale factors the global mean scale factor decreases by 0 17 to gain accurate mass estimates ocean bottom pressure obp time series derived from the mascon solutions are shown to have greater correlation with in situ data than do spherical harmonic solutions increase in correlation coefficient of 0 08 globally particularly in low latitude regions with small signal power increase in correlation coefficient of 0 35 regionally in addition to reducing the error rms with respect to the in situ data reduction of 0 37 cm globally and as much as 1 cm regionally greenland and antarctica mass balance estimates derived from the mascon solutions agree within formal uncertainties with previously published results computing basin averages for hydrology applications shows general agreement between harmonic and mascon solutions for large basins however mascon solutions typically have greater resolution for smaller spatial regions in particular when studying secular signals

time variability of the earth s gravity field hydrological and oceanic effects and their possible detection using grace the grace satellite mission scheduled for launch in 2001 is designed to map out the earth s gravity field to high accuracy every 2 4 weeks over a nominal lifetime of 5 years changes in the gravity field are caused by the redistribution of mass within the earth and on or above its surface grace will thus be able to constrain processes that involve mass redistribution in this paper we use output from hydrological oceanographic and atmospheric models to estimate the variability in the gravity field i e in the geoid due to those sources we develop a method for constructing surface mass estimates from the grace gravity coefficients we show the results of simulations where we use synthetic grace gravity data constructed by combining estimated geophysical signals and simulated grace measurement errors to attempt to recover hydrological and oceanographic signals we show that grace may be able to recover changes in continental water storage and in seafloor pressure at scales of a few hundred kilometers and larger and at timescales of a few weeks and longer with accuracies approaching 2 mm in water thickness over land and 0 1 mbar or better in seafloor pressure

a study of the factors influencing the occurrence of landslides in the wushan area due to the complex natural geological conditions many slope related geological hazards occur in the three gorges reservoir area in china this study focuses on the characteristics of landslide development and their underlying mechanisms in this area a statistical analysis is conducted to determine the characteristics of landslide development in the wushan area including the landslide distribution as a function of the elevation slope landslide material composition scale lithology boundary conditions instability mechanism stratigraphic age attitude and sliding direction the mechanisms of slope instability and the effect on the occurrence of landslides are analyzed this study provides important reference material for landslide research in the three gorges reservoir area and similar stratigraphic areas

experimental investigation of rainfall criteria for shallow slope failures a theory of the internal response based rainfall criterion for predicting slope failure is proposed based on artificial rainfall tests for a sandy slope key elements in a generic model describing shallow slope failure are identified from the tests with extensive soil moisture and piezometric measurements the observed retrogressive slope failure was triggered by a toe failure followed by an abrupt increase in debris discharge the onset of the failure was preceded by a clear transition point on the soil moisture vs time curve at the soil bedrock interface both external and internal responses of slopes to rainfall can be expressed using widely adopted i d rainfall intensity duration plots experimental results from the tests indicate close relationships between the internal based and external based i d envelopes for critical slope states the theory of the internal based i d criterion proposed here will be useful for more accurate slope failure predictions

hydrologic conditions responsible for triggering the stože landslide slovenia in two events on november 15 and 17 2000 near the mangart mountain 2679 m a s l nw slovenia two translational landslides debris flow slides with a total volume of more than 1 5 million m3 occurred on the sto e slope composed of morainic material filled with silt fraction the first landslide was associated with a dry and the second landslide with a wet debris flow respectively the rain gauging station in the village of log pod mangartom recorded 1638 4 mm of rainfall more than 60 of the average annual precipitation in the 48 days before the events rainfall intensity of 1 42 mm h in 1152 h the recorded rainfall depth has a recurrence interval of more than 100 years other recorded rainfall depths of shorter duration 481 6 mm in 7 days 174 0 mm in 24 h 70 mm in 1 h have recurrence intervals of much less than 100 years a hydrological analysis of the event showed that the increase in runoff coefficients during the wet period in autumn 2000 before the landslide was as high as two to threefold an analysis using natural isotopes of 18o and tritium of water samples from the sto e landslide area has shown permanent but slow exfiltration of underground waters from a reservoir in the slope in the case of low intensity and long duration rainfall in autumn 2000 relatively low permeable 10 7 m s morainic material was nearly saturated but remained stable average porosity 21 water content 20 liquid limit 25 until high artesian pressures up to 100 m developed in the slope by slow exfiltration from the relatively high permeable 10 5 m s massive dolomite the sto e landslide two debris flow slides was triggered by high artesian pressures built in the slope after long duration rainfall the devastating debris flows formed from the landslide masses by infiltration of rainfall and surface runoff into the landslide masses and by their liquefaction

assessment of age origin and sustainability of fossil aquifers a geochemical and remote sensing based approach abstract an integrated approach was developed to assess the sustainability origin age evolution and groundwater potential of large fossil aquifers using the mega aquifer system mas area 2 106 km2 in the arabian peninsula as a test site a two step exercise was adopted the sustainability of the mas was first investigated through the analysis of grace data and land surface model lsm outputs then integrated geochemical remote sensing and field studies were conducted to address the age origin hydrogeological setting and evolution of the southern sections of the mas rub al khali aquifer system rakas the area identified from the analysis of grace and lsms as being the most suited for sustainable development analysis of grace and lsms revealed 1 the mas central and northern sections are experiencing high groundwater extraction 6 6 km3 yr and depletion rates 2 8 0 8 km3 yr with minimum balancing potential through aquifer capture processes yet sustainability could be achieved by reducing annual extraction by 2 8 km3 and 2 the mas southern sections rub al khali aquifer system rakas are experiencing low groundwater depletion rates eastern rakas 1 8 1 4 mm yr to steady state conditions western rakas 0 73 1 4 mm yr geochemical remote sensing and field investigations over the rakas revealed 1 the presence of west to east trending drainage networks and large scale groundwater flow systems consistent with a meteoric source precipitation over red sea hills 2 increasing 36cl model ages along groundwater flow directions up to 970 000 years indicating aquifer recharge in wet pleistocene periods 3 progressive depletion in the o and h stable isotopic compositions of aquifers with increasing distance from the red sea hills basement outcrops indicating modest recharge during prevailing dry conditions and 4 the presence of relatively fresh tds 800 2800 mg l and non radioactive 226ra 228ra

occurrence conditions of roll waves for three grain fluid models and comparison with results from experiments and field observation for the flow and deposition behaviour of debris flows phenomena like particle sorting levee formation and the development of roll waves are expected to be important processes however these processes are not well understood and hardly implemented in modelling approaches in this study we focus on the development of roll waves and derive advanced criteria separating stable and instable flow regimes for three debris flowmodels these criteria are expressed using critical froude numbers each of these simple flow models reflect different sources of flow resistance laminar viscous stress bingham type dispersive stress due to particle collision bagnold type and a model combining turbulent and dispersive stresses subsequently we compare the predictions from these models with results from laboratory experiments with grain fluid mixtures in a straight flume and with observations from a debris flow monitoring site at the lattenbach creek in austria the experimental flows match with a turbulent flow model including particle collisions for the natural flows the connection between models and observations is not clear due to limited field data the results of our study contribute to an improved determination of critical flow conditions and provide data for model testing

seismogeological effects on rocks during the 12 april 1998 upper soca territory earthquake nw slovenia abstract on 12 april 1998 the strongest earthquake m l 5 7 with an epicentre in slovenia in the last 100 years shook the upper soca territory nw slovenia its maximum intensity was between vii and viii according to the european macroseismic scale ems 98 its epicentre is located in the area se of the town of bovec in the krn mountain range julian alps apart from substantial material damage to nearby settlements the earthquake caused considerable changes to the landscape through many rockfalls and landslides in this paper we try to assess the effects of this event on the natural surroundings the presented results are useful to understand the relation between seismogeological effects and the intensity scale ems 98 for this particular event but might also be a first step towards a future statistically meaningful assessment of the intensity scale on the basis of seismogeological effects

increasing subsurface water storage in discontinuous permafrost areas of the lena river basin eurasia detected from grace tws increase of 32 10 km 3 yr for the entire basin equivalent to an increase in water thickness of 1 3 0 4 cm yr over a basin of 2 4 million km 2 we compare tws estimates from grace with time series of precipitation p minus evapotranspiration et from era interim reanalysis minus observational river discharge r we find an excellent agreement in annual and inter annual variability between the two time series furthermore we find that a bias of 20 10 in p et is sufficient to effectively close the waterbudgetwith grace when we account for this bias the time series of cumulative tws from grace and climatological data agree to within 3 8 cm of water thickness or 9 of the mean annual p the tws increase is not uniform across the river basin and exhibits a peak over an area of 502 400 km 2 centered at 118 5e 62 5n and underlain by discontinuous permafrost in this region we attribute the observed tws increase of 68 19 km 3 to an increase in subsurface water storage this large subsurface water signal will have a significant impact on the terrestrial hydrology of the region including increased baseflow and alteration of seasonal runoff citation velicogna i j tong t zhang and j s kimball 2012 increasingsubsurfacewater storage in discontinuous permafrost areas of the lena river basin eurasia detected from grace geophys res lett 39 l09403 doi 10 1029 2012gl051623

effectiveness of exceptional rainstorms on a small mediterranean basin abstract a comprehensive investigation of rainstorms and their consequent impacts on landscape evolution is geomorphologically important but only scant information may be available on exceptional events because parameters on synoptic conditions rainstorm landforms and hydrology for such events may be incomparable with previous knowledge we studied an exceptional storm on april 2 2006 in the ramot menashe region israel our investigation of rainfall landslides debris flows and channel suggests the effectiveness of such an event on the development of basin scale morphology the storm caused damage and casualties although it covered relatively narrow strips neither direct rainfall nor runoff measurements exist for the most severely affected area of ramot menashe but the geomorphologic evidence combined with high resolution meteorological radar data provides the basic understanding of the processes and hazardous conditions which prevailed at the time in the storm core based on estimation from meteorological radar data 263 mm of rain fell within 3 h with a maximum intensity of 220 mm h 1 for 10 min triggering both sporadic landslides at the soil bedrock contact on the upper slopes and widespread landslides at the fractured massive bedrock contact on the lower slopes the 1st order channels on the alternation of chalk and marl also underwent erosion and the produced sediment deposited on alluvial fans at the confluence with the main channel the specific peak discharges for catchment size of 0 3 10 km2 were 11 to 73 m3 s 1 km 2 higher than any recorded floods in the mediterranean climatic region of israel the effectiveness of the flood for geomorphic work represented by shear stress and stream power per unit boundary area reached 87 398 n m 2 and 212 2134 w m 2 respectively this kind of analysis can be applied to hazard prediction in other areas under similar geomorphological conditions

hydrological changes and vertical crustal deformation in south india inference from grace gps and absolute gravity data abstract monsoon rainfall over indian subcontinent causes large hydrological changes that deform the earth on varied time scale the seasonal hydrological mass changes are in the range of 20 50 cm of equivalent water height over southern india which causes vertical deformation of 1 2 cm we compare the deformation computed from grace mass signal with that of height changes from continuous gps data from two locations in south india and find that the amplitude and phases of seasonal vertical deformation derived from both gps and grace are consistent indicating that hydrological effects are major cause of periodic deformation in the region this supports the earlier deduction that grace data can be utilized to remove hydrological effects from gps data high precision absolute gravity values measured near the gps location and groundwater levels measured in the boreholes corroborate the space based observations of hydrological changes and vertical deformation gps and grace data also indicate inter annual variation caused due to rainfall variability signifying that hydrological effects must be removed before deriving any long term vertical deformation trend

sediment production and delivery from recent large landslides and earthquake induced rock falls in the upper soca river valley slovenia abstract landsliding not only changes the morphology of the terrain but is also an effective factor in sediment production extreme events such as earthquake induced large rock falls or rainfall induced landslides may during the event itself or in a period after it greatly increase the sediment delivery and river sediment transport the effects of strong earthquakes and large landslides on sedimentation are evident in the upper soca river basin nw slovenia the annual sediment production in the headwaters of this typical alpine valley in western slovenia is estimated to average 1000 m 3 km 2 a 1 in the last few years two large landslides triggered there were of comparable volume but differed regarding sediment delivery to the fluvial network the 2000 sto e landslide at 1 5 million m 3 was a debris flow that delivered more than 1 million m 3 to the koritnica river the strug complex landslide was initiated in 2001 by a rock slide and soon amounted to an estimated volume of 310 000 m 3 in 2002 it released over 20 rainfall induced debris flows on the order of 100 to 1000 m 3 to the fluvial system in mountainous terrain in the headwaters of the upper soca river slope failures may occur during strong earthquakes depending on the event magnitude the earthquake of april 12 1998 m s 5 6 caused more than 100 failures among them 50 rock falls about 260 000 m 3 of rock fall material will remain on hill slopes with no potential of reaching the river network while an estimated volume of 480 000 m 3 may be released to watercourses in a longer period during extreme events about 200 000 m 3 of rock fall debris was deposited in areas from where the material was released to watercourses during rainfall events as a consequence of the 1998 earthquake hyperconcentrated flows were observed during floods in some torrential tributary channels of the upper soca river after the earthquake of july 12 2004 m s 4 9 50 rather superficial slope failures including 38 rock falls were registered from 2000 until 2004 more than 150 000 m 3 sediments were dredged from the upper soca river channel

debris flooding magnitude estimation based on relation between dendrogeomorphological and meteorological records abstract debris floods are mass movement events which are usually triggered by intense short duration rainfall events they often occur on alluvial fans in an alpine environment due to their sever geohazard potential they pose a serious threat to infrastructure and human life to minimize their threat understanding of their past magnitude occurrence is crucial dendrogeomorphology has proven to be a highly useful method in studies of past slope mass movements however establishing magnitudes of past events has so far been based on indirect indicators such as spatial distribution of affected trees characteristics of tree injures and sedimentological records in this study we present a method that directly estimates the magnitudes of past debris flood events on an alluvial fan using dendrogeomorphological and meteorological data sets the studied dendrogeomorphological data set is based on tree ring series from 105 sampled trees picea abies abies alba and larix decidua growing on an active alluvial fan in a typical alpine environment of the julian alps in nw slovenia based on sudden growth suppression thirteen debris flood events since 1903 were dated meteorological data from a nearby meteorological station was used to determine the exact triggering meteorological event for ten events comparing the it index of affected trees and calculated return period of an individual triggering meteorological event established the magnitude of debris flooding we showed that more trees are affected at high return period intensity of the triggering meteorological event and therefore higher magnitudes of debris floods this research presents the first combined use of dendrogeomorphological and meteorological data sets for magnitude estimation of historic debris flood events which could be successfully applied in similar environments

regionalization of rainfall thresholds an aid to landslide hazard evaluation rainfall soil properties and morphology are major factors controlling shallow landsliding a series of meteorological events that triggered soil slips in northern italy were studied to define rainfall thresholds and to evaluate a possible regionalization soil properties triggering rainfall and local lithological and morphometrical settings of different sites were used as input to an infiltration model the approach allows the recognition of several triggering conditions in the piedmont pre alpine and alpine regions this suggests the need for different rainfall thresholds with respect to those derived with other methods intensity versus rainfall duration relationships become particularly important when related to soil permeability and thickness and demonstrate the role of antecedent precipitation events with exceptional water discharge from obstructed road culverts reveal the role played by anthropic structures in triggering such phenomena different approaches to slope stability analysis are shown taking into account bedrock lithology topography seepage and local saturation conditions

failure characteristics of rainfall induced shallow landslides in granitic terrains of shikoku island of japan soil slips debris slides and flow occurrences on hill slopes of particular areas are closely related to the mode of rainfall because of geological geomorphological and climatic settings japan is highly prone to rainfall induced landslides in 2004 shikoku the smallest island of japan faced extreme events of typhoon rainfalls and suffered huge losses of life and property because of floods and landslides this paper deals with the synoptic descriptions of failures that occurred in the granitic terrain of northeast shikoku island japan along with rainfall and failure relationships during the typhoon 0423 tokage of 2004 examples of typical failures that occurred in moriyuki and monnyu of northeast shikoku are taken into consideration in this study data from laboratory and field were used to perform sensitivity and stability analyses with respect to varying slope angles strength parameters and thicknesses of saturated residual soil this study attempts to employ a standard method of stability analysis of translational slides which are very common in masa soil weathered granite during extreme rainfall average rainfall intensities and duration during typhoon tokage were also used to interpret landslide triggering thresholds for the study area

dynamic earth system and ecological controls of rainfall initiated landslides abstract rainfall initiated landslides continue to inflict damages and loss of life throughout the world processes and mechanisms revealed from hydrological geomorphic geotechnical pedological geological hydrochemical and biological investigations have advanced our understanding of these effects on slope stability however the interactions amongst these processes and attributes as they affect the initiation and propagation of landslides are not as well understood too often landslide studies are conducted from only one or at most two of these perspectives moreover while precipitation and hydrology are recognized as dynamic influences the earth system and ecological effects are often assumed to be static we assess the interplay of these processes related to landslides triggered by positive pore water accretion and loss of soil suction each of these conditions arguably requires a different view on the processes that cause slope failure and predictive approaches this review starts from the perspective of dynamic adapting earth and ecological systems and discusses how these attributes relate to landslide initiation mode location and timing specifically the role that large and small scale preferential flow plays in both contributing to and mitigating instability is elucidated including effects of bedrock exfiltration we also examine how and under what conditions these pathways manifest in different soils lithology and landforms the multiple effects of rhizosphere processes on slope stability are discussed including root reinforcement evaporation from canopies and litter layers transpiration and the role of root structure affecting preferential flow paths rainfall initiated landslides involve highly dynamic hydrologic earth surface and ecological processes that persist over a range of spatial and temporal scales however guidance for overcoming these challenges has been elusive a conceptual framework is presented to shed light on these dynamic and interactive processes that should lend insights into why and when certain slopes fail during storms while other seemingly similar slopes do not fail such advances will benefit landslide hazard assessments and disaster responsiveness protocols

a methodology for regionalizing 3 d effective porosity at watershed scale in crystalline aquifers 13 an innovative approach for regionalizing the 3 d effective porosity field is presented and 14 applied to two large overexploited and deeply weathered crystalline aquifers located in 15 southern india the method derives from earlier work on regionalizing a 2 d effective 16 porosity field in that part of an aquifer where the water table fluctuates which is now 17 extended over the entire aquifer using a 3 d approach a method based on geological and 18 geophysical surveys has also been developed for mapping the weathering profile layers 19 saprolite and fractured layers the method for regionalizing 3 d effective porosity 20 combines water table fluctuation and groundwater budget techniques at various cell sizes 21 with the use of satellite based data for groundwater abstraction the structure of the 22 weathering profile and geostatistical techniques the approach is presented in detail for the 23 kudaliar watershed 983 km 2 and tested on the 730 km 2 anantapur watershed at watershed 24 scale the effective porosity of the aquifer ranges from 0 5 to 2 in kudaliar and between 25 0 3 and 1 in anantapur which agrees with earlier works results show that i depending 26 on the geology and on the structure of the weathering profile the vertical distribution of 27 effective porosity can be very different and that the fractured layers in crystalline aquifers are 28 not necessarily characterized by a rapid decrease in effective porosity and ii that the lateral 29 variations in effective porosity can be larger than the vertical ones these variations suggest 30 that within a same weathering profile the density of open fractures and or degree of 31 weathering in the fractured zone may significantly varies from a place to another 32 the proposed method provides information on the spatial distribution of effective porosity 33 which is of prime interest in terms of flux and contaminant transport in crystalline aquifers 34 implications for mapping groundwater storage and scarcity are also discussed which should 35 help in improving groundwater resource management strategies 36 37

case study numerical simulations of debris flow below stoze slovenia in november 2000 a landslide debris flow with a volume of 1 2 106 m3 slid down from sto e mountain in nw slovenia it partly or totally destroyed 23 buildings in the village of log pod mangartom a

estimating the human contribution to groundwater depletion in the middle east from grace data land surface models and well observations data from the gravity recovery and climate experiment grace satellite mission are used to estimate monthly changes in total water storage across the middle east during february 2003 to december 2012 the results show a large negative trend in total water storage centered over western iran and eastern iraq subtracting contributions from the caspian sea and two large lakes tharthar and urmiah and using output from a version of the clm4 5 land surface model to remove contributions from soil moisture snow canopy storage and river storage we conclude that most of the long term water loss is due to a decline in groundwater storage by dividing the region into seven mascons outlined along national boundaries and fitting them to the data we find that the largest groundwater depletion is occurring in iran with a mass loss rate of 25 3 gt yr during the study period the conclusion of significant iranian groundwater loss is further supported by in situ well data from across the country anthropogenic contributions to the groundwater loss are estimated by removing the natural variations in groundwater predicted by clm4 5 these results indicate that over half of the groundwater loss in iran 14 3 gt yr may be attributed to human withdrawals

landslide fluidization process by flume experiments abstract an almost real size slope model was used to study the generation process of landslide fluidization during torrential rain experiments were conducted by filling an inclined flume with loose sand and spraying water over the flume with a rainfall simulator to induce the sand to collapse both the movement volumetric strain and the pore water pressure of the sand were monitored throughout the experiments from the start of spraying to the cessation of the landslide our experiments showed the following 1 landslide fluidization caused by undrained sudden loading undergoes three stages compaction of the sand layer by the sliding mass from upper slope generation of excess pore water pressure in saturated zone and induction of fast shearing 2 fluidization at the collapse source area also undergoes three stages destruction and compaction of sand layer skeleton by outbreak of shearing increase of pore water pressure in saturated zone and shift to fast shearing but these three stages take place almost simultaneously

recent contributions of glaciers and ice caps to sea level rise satellite measurements of earth s gravity field show that the mass loss of glaciers and ice caps contributed to sea level rise by approximately 0 4 millimetres per year between 2003 and 2010 the extent to which mass loss from ice covered land areas contributes to sea level rise is not known accurately in part because previous global estimates use different techniques for glaciers ice caps and ice sheets the gravity recovery and climate experiment grace satellite has provided monthly measurements of the global gravity field since 2002 using grace data jacob et al assess regional mass loss between 2003 and 2010 and conclude that mass loss from ice covered land areas contributed almost 1 5 mm per year to the sea level rise estimated mass loss from the high mountains of asia was negligible in contrast to some other reports glaciers and ice caps gics are important contributors to present day global mean sea level rise1 2 3 4 most previous global mass balance estimates for gics rely on extrapolation of sparse mass balance measurements1 2 4 representing only a small fraction of the gic area leaving their overall contribution to sea level rise unclear here we show that gics excluding the greenland and antarctic peripheral gics lost mass at a rate of 148 30 gt yr 1 from january 2003 to december 2010 contributing 0 41 0 08 mm yr 1 to sea level rise our results are based on a global simultaneous inversion of monthly grace derived satellite gravity fields from which we calculate the mass change over all ice covered regions greater in area than 100 km2 the gic rate for 2003 2010 is about 30 per cent smaller than the previous mass balance estimate that most closely matches our study period2 the high mountains of asia in particular show a mass loss of only 4 20 gt yr 1 for 2003 2010 compared with 47 55 gt yr 1 in previously published estimates2 5 for completeness we also estimate that the greenland and antarctic ice sheets including their peripheral gics contributed 1 06 0 19 mm yr 1 to sea level rise over the same time period the total contribution to sea level rise from all ice covered regions is thus 1 48 0 26 mm 1 which agrees well with independent estimates of sea level rise originating from land ice loss and other terrestrial sources6

irrigation as a potential driver for anomalous glacier behavior in high mountain asia many glaciers in the northwest of high mountain asia hma show an almost zero or positive mass balance despite the global trend of melting glaciers this phenomenon is often referred to as the karakoram anomaly although strongest positive mass balances can be found in the kunlun shan mountain range northeast of the karakoram using a regional climate model in combination with a moisture tracking model we show that the increase in irrigation intensity in the lowlands surrounding hma particularly in the tarim basin can locally counter the effects of global warming on glaciers in kunlun shan and parts of pamir and northern tibet through an increase in summer snowfall and decrease in net radiance irrigation can thus affect the regional climate in a way that favors glacier growth and future projections of glacier melt which may impact millions of inhabitants surrounding hma will need to take into account predicted changes in irrigation intensity