topographic controls on the surface energy balance of a high arctic valley glacier 1 this paper presents the results of a distributed two dimensional surface energy balance model used to investigate the spatial and temporal variations in the surface energy balance of midre lovenbreen a small valley glacier in northwest spitsbergen svalbard over the summer of 2000 we utilize high resolution airborne lidar data to derive a digital elevation model of the glacier and surrounding topography on which a surface energy balance is computed driven by meteorological data obtained from a meteorological station located on the glacier and a synoptic station maintained at the nearby ny alesund research base given the high resolution topographic data we focus particularly on whether the long duration of sunshine at high latitudes compensates for the higher solar zenith angles on the season long energy balance and whether shading by the surrounding topography plus glacier surface slope and aspect play an increased role in the patterns of solar radiation receipt and hence melt over the glacier surface the model results are validated using a combination of mass balance data from the glacier measured surface lowering at the glacier meteorological station and by comparing a derived energy balance component from the model with a measured energy flux overall the model performance is very good glacier topography is found to play a fundamental role in determining the surface energy balance topographic shading slope and aspect and correction of the surface albedo for high solar zenith angles are found to play a crucial role in determining spatial patterns of surface energy balance and therefore melt

periglacial cirque analogs elevation trends of cryoplanation terraces in eastern beringia abstract cryoplanation terraces are large erosional landforms common in cold unglaciated mountainous environments terrace sequences are composed of alternating slope segments with gently sloping treads and steep rubble covered risers and culminate in extensive summit flats many unglaciated upland landscapes in eastern beringia are dominated by these landforms indirect evidence indicates that they evolve through locally intensified weathering and mass movement processes associated with late lying snowcover geospatial analysis involving nearly 700 cryoplanation terraces in eastern beringia demonstrates that their elevation rises from 175 to 350 masl on bering sea islands to median values 1200 m near the alaska canada border the regional trends of cryoplanation terrace elevation are nearly identical to those of wisconsinan cirques on several transects across alaska the consistency in the elevation trends of glacial cirques and cryoplanation terraces indicates close genetic links between the two classes of feature involving topographic position continentality gradients and the mass balance of localized snow accumulations cryoplanation terraces can be considered the periglacial analogs of glacial cirques and have greater potential as sources of paleoclimatic information than smaller periglacial features more sensitive to short term climate variations process oriented studies age determinations and high resolution mapping are needed before the paleoenvironmental potential of these landforms can be realized fully

stable isotope based paleoaltimetry abstractthe quantitative estimation of paleoaltitude has become an increasing focus of earth scientists because surface elevation provides constraints on the geodynamic mechanisms operating in mountain belts as well as the influence of mountain belt growth on regional and global climate the general observation of decreasing 18o and 2h values in rainfall as elevation increases has been used in both empirical and theoretical approaches to estimate paleoelevation these studies rely on the preservation of ancient surface water compositions in authigenic minerals to reconstruct the elevation at the time the minerals were forming in this review we provide a theory behind the application of stable isotope based approaches to paleoaltimetry we apply this theory to test cases using modern precipitation and surface water isotopic compositions to demonstrate that it generally accords well with observations examples of the application of paleoaltimetry techniques to himalaya tibet and the andes are discussed

the search for fullerenes in rocks from the ries impact crater since their discovery fullerenes have been reported from various geological environments one group of these findings has been related to bolide impacts e g the sudbury crater and the k t and p t boundaries impact rocks of the ries crater germany including samples of suevites metamorphosed crystalline clasts and glass bombs have been collected in the otting altebrg and seelbronn quarries no fullerenes in concentrations above 1 ppb have been found in analyzed samples laser desorption time of flight mass spectrometry ld tof ms confirmed the absence of fullerenes in the analyzed samples these results support the concept that the ries impactor was a stony meteorite

projections of glacier change in the altai mountains under twenty first century climate scenarios we project glacier surface mass balances of the altai mountains over the period 2006 2100 for the representative concentration pathway rcp 4 5 and rcp8 5 scenarios using daily near surface air temperature and precipitation from 12 global climate models in combination with a surface mass balance model the results indicate that the altai glaciers will undergo sustained mass loss throughout the 21st for both rcps and reveal the future fate of glaciers of different sizes by 2100 glacier area in the region will shrink by 26 10 for rcp4 5 while it will shrink by 60 15 for rcp8 5 according to our simulations most disappearing glaciers are located in the western part of the altai mountains for rcp4 5 all glaciers disappearing in the twenty first century have a present day size smaller than 5 0 km2 while for rcp8 5 an additional 7 of glaciers in the initial size class of 5 0 10 0 km2 also vanish we project different trends in the total meltwater discharge of the region for the two rcps which does not peak before 2100 with important consequences for regional water availability particular for the semi arid and arid regions this further highlights the potential implications of change in the altai glaciers on regional hydrology and environment

suitability of a constant air temperature lapse rate over an alpine glacier testing the greuell and bohm model as an alternative near surface air temperature typically measured at a height of 2 m is the most important control on the energy exchange and the melt rate at a snow or ice surface it is distributed in a simplistic manner in most glacier melt models by using constant linear lapse rates which poorly represent the actual spatial and temporal variability of air temperature in this paper we test a simple thermodynamic model proposed by greuell and bohm in 1998 as an alternative using a new dataset of air temperature measurements from along the flowline of haut glacier d arolla switzerland the unmodified model performs little better than assuming a constant linear lapse rate when modified to allow the ratio of the boundary layer height to the bulk heat transfer coefficient to vary along the flowline the model matches measured air temperatures better and a further reduction of the root mean square error is obtained although there is still considerable scope for improvement the modified model is shown to perform best under conditions favourable to the development of katabatic winds few clouds positive ambient air temperature limited influence of synoptic or valley winds and a long fetch but its performance is poor under cloudy conditions

the response of glaciers to intrinsic climate variability observations and models of late holocene variations in the pacific northwest discriminating between glacier variations due to natural climate variability and those due to true climate change is crucial for the interpretation and attribution of past glacier changes and for the expectations of future changes we explore this issue for the well documented glaciers of mount baker in the cascades mountains of washington state usa using glacier histories glacier modeling weather data and numerical weather model output we find that natural variability alone is capable of producing kilometer scale excursions in glacier length on multi decadal and centennial timescales such changes are similar in magnitude to those attributed to a global little ice age the null hypothesis that no climate change is required to explain the glacier fluctuations in this setting cannot be rejected these results for mount baker glaciers are also consistent with an earlier study analyzing individual glaciers in scandinavia and the alps the principle that long timescale fluctuations of glacier length can be driven by short timescale fluctuations in climate reflects a robust and fundamental property of stochastically forced physical systems with memory it is very likely that this principle also applies to other alpine glaciers and that it therefore complicates interpretations of the relationship between glacier and climate history however the amplitude and timescale of the length fluctuations depends on the details of the particular glacier geometry and climatic setting and this remains largely unevaluated for most glaciers

occurrence of natural fullerenes in low grade metamorphosed proterozoic shungite from karelia russia abstract we report on the occurrence of fullerenes in proterozoic shungite 2 ga from the shungite mine kondopoga karelia russia 62 12 n 34 17 e the presence of fullerenes has been confirmed by mass spectrometry with peaks at 360 and 720 amu atomic mass unit powder x ray diffraction showing ten diffraction peaks corresponding to the fullerite structure with a 1 4201 5 nm and 13 c nuclear magnetic resonance nmr spectroscopic studies showing a peak at 143 2 ppm in the kondopoga shungite mine fullerenes occur in silty shales that have experienced greenshist facies metamorphism

south cascade glacier mass balance 1935 2006 a simple model uses daily observations of precipitation and temperature at a nearby weather station to estimate glacier average seasonal mass balance components at south cascade glacier washington usa from 1935 24 years before measurements began at the glacier this is 13 years earlier than measurements that can be derived using the ncep ncar reanalysis database begins 1 january 1948 although the model s error in estimating winter balance and summer balance over 1959 2006 is greater than that of a model using the reanalysis database its error in estimating net balance is comparable the model uses an empirically determined precipita tion ratio between the station and the glacier and a seasonally varying temperature lapse rate de termined from 9 years of measurements at the glacier temperature is used with a degree day for mulation to estimate ablation and to partition precipitation between rain and snow for estimating accumulation both processes are assumed to exist throughout the year and model results are compared seasonally with adjusted observations of winter and summer balances the published mass balance series is adjusted to a constant topography 1970 series in an attempt to remove the influence of changing topography on the glacier s response to climate the reconstructed values prior to 1959 are also with respect to the 1970 glacier topography because precipitation is measured at the weather station rather than being inferred from other meteorological variables it enables us to distinguish more accurately between wet day and dry day conditions including vertical lapse rates of temperature

simulating arctic climate warmth and icefield retreat in the last interglaciation in the future arctic warming and the melting of polar glaciers will be considerable but the magnitude of both is uncertain we used a global climate model a dynamic ice sheet model and paleoclimatic data to evaluate northern hemisphere high latitude warming and its impact on arctic icefields during the last interglaciation our simulated climate matches paleoclimatic observations of past warming and the combination of physically based climate and ice sheet modeling with ice core constraints indicate that the greenland ice sheet and other circum arctic ice fields likely contributed 2 2 to 3 4 meters of sea level rise during the last interglaciation

origins of fullerenes in rocks this article is a technical comment and author response to the the discovery of naturally occuring fullerenes in shunga rock samples the commenting researchers did not find detectable amounts of fullerenes in a variety of carbon rich rocks they hypothesize that the fullerenes found in the shunga sample were probably a localized event the original researchers buseck and tsipursky provide a rebuttal with further comments including parallels to other minerological occurences all agreed that more data are needed 10 refs

surface temperature lapse rates over complex terrain lessons from the cascade mountains lapse rates of 3 9 5 2 c km 1 substantially smaller than the often assumed 6 5 c km 1 the data sets show similar seasonal and diurnal variability with lapse rates smallest 2 5 3 5 c km 1 in late summer minimum temperatures and largest 6 5 7 5 c km 1 in spring maximum temperatures geographic windward versus lee side differences in lapse rates are found to be substantial using a simple runoff model we show the appreciable implications of these results for hydrological modeling

altitudinal climatic index changes in subtropical china indicated from branched glycerol dialkyl glycerol tetraethers proxies abstract branched glycerol dialkyl glycerol tetraethers brgdgts have been widely applied in climate parameter reconstructions over the past few years mbt 5me the methylation of branched tetraethers based on the 5 methyl isomers and cbt cyclisation of branched tetraethers that includes 6 methyl brgdgts in the numerator have proven to be useful brgdgt proxies for interpreting the mean annual air temperature mat and soil ph of different climate condition areas in china however the application of mbt 5me and cbt for indicating altitudinal climate conditions is still open to discussion e g the lack of comparisons between attitudinal results from mountain areas of different climate conditions in this study we compared soil brgdgt along three mountain transects in subtropical china i e mt gaoligong mt fanjing and mt shennongjia the brgdgt distributions of mt gaoligong and mt fanjing were similar to the subtropical surface soil brgdgt distribution pattern featured by the dominance of chemical structures of brgdgts ia and iia however mt shennongjia was characterised by increasing brgdgts iiia iia iib and ib much like the semi humid humid temperate climate area brgdgt distribution pattern these results indicate that altitudinal climate indicators such as temperature and precipitation could be recorded by varied brgdgt distributions also mbt 5me inferred mats were negatively correlated with mountain altitude r2 0 79 0 87 the mat lapse rate increased from mt shennongjia to mt fanjing to mt gaoligong 0 5 c 100 m 0 9 c 100 m and 1 3 c 100 m respectively the influence of the qinghai tibetan plateau ice cover and differences in latitudinal temperature and or moisture conditions might be the reasons for the various lapse rates the soil ph was less correlated with altitude r2 0 58 0 63 than to the regression of mat and altitude showing slightly different relations from those of horizontal studies at mt gaoligong and mt fanjing soil ph and altitude demonstrated positive linear regressions but with different slopes the different reducing rate of soil ph as a function of altitude for the two mountains is probably caused by their dominating summer monsoons for mt shennongjia where the climate condition is less humid than mt gaoligong and mt fanjing the soil ph did not significantly change with altitude and thus no relationship was observed this might probably be partially induced by the weakly alkaline parent rocks of mt shennongjia

testing for fullerenes in geologic materials oklo carbonaceous substances karelian shungites sudbury black tuff comment and reply reply buseck et al s 1992 1 discovery of fullerenes in fractures in a shungite sample enclosed in diabase from russian karelia has been followed by several substantiating reports see buseck 2002 2 p 785 as well as by conflicting reports e g ebbesen et al 1995 3 mossman et al

a giant palaeoproterozoic deposit of shungite in nw russia genesis and practical applications abstract occurrences of 2 0 ga mature organic material from the lake onega area nw russia constitute one of the most remarkable accumulations of organic carbon from the palaeoproterozoic the deposit occurs in a 1000 m sedimentary volcanic succession developed over an area of 9000 km 2 with an estimated total carbon reserve exceeding 25 10 10 tonnes the organic material occurs in the form of the mineraloid shungite which is a black non crystalline semi metallic material that contains 98 wt c the shungite bearing rocks were accumulated within a volcanic continental rift setting in a non euxinic brackish water lagoonal environment developed on the rifted margin of the archaean craton the occurrences of shungite bearing rocks represent a combination of a petrified oil field petrified organosiliceous diapirs and oil spills these are exemplified by three types of deposit i in situ stratified ii migrated diapirs and iii redeposited clastic in situ stratified deposits are composed of metamorphosed oil shales 80 wt c diapiric deposits form non stratified cupolas or mushroom shaped bodies composed of shungite containing 35 75 wt sio 2 and 20 55 wt c these are considered to represent organosiliceous rocks originally gels or mud the shungite rocks show abundant shrinkage cracks cryptic fluidal textures and brecciation caused by multiple fluidisation processes the current data are consistent with either diapiric or mud volcanic origins occurrences of clastic shungite are hosted by lacustrine volcanoclastic greywackes deposited from turbiditic flows shungite occurs in rocks as shungite has a heterogeneous molecular structure in which carbon occurs as 10 nm globules irregularly distributed within carbon showing no structure the unusual physicochemical and structural properties of shungite are used in diverse industrial and environmental applications including metallurgy water purification thermolysis and organosynthesis of cyclic hydrocarbons shungite is an effective sorbent for removal of organic and inorganic substances pathogenic bacteria and heavy metals from contaminated water

spatial and temporal variability of air temperature on a melting glacier atmospheric controls extrapolation methods and their effect on melt modeling juncal norte glacier chile 1 temperature data from three automatic weather stations and twelve temperature loggers are used to investigate the spatiotemporal variability of temperature over a glacier its main atmospheric controls the suitability of extrapolation techniques and their effect on melt modeling we use data collected on juncal norte glacier central chile during one ablation season we examine temporal and spatial variability in lapse rates lrs together with alternative statistical interpolation methods the main control over the glacier thermal regime is the development of a katabatic boundary layer kbl katabatic wind occurs at night and in the morning and is eroded in the afternoon lrs reveal strong diurnal variability with steeper lrs during the day when the katabatic wind weakens and shallower lrs during the night and morning we suggest that temporally variable lrs should be used to account for the observed change they tend to be steeper than equivalent constant lrs and therefore result in a reduction in simulated melt compared to use of constant lrs when extrapolating from lower to higher elevations in addition to the temporal variability the temperature elevation relationship varies also in space differences are evident between local lrs and including such variability in melt modeling affects melt simulations extrapolation methods based on the spatial variability of the observations after removal of the elevation trend such as inverse distance weighting or kriging do not seem necessary for simulations of gridded temperature data over a glacier

appalachian cold air damming abstract appalachian cold air damming is investigated by means of 1 a 50 yr monthly climatology 2 a synoptic case study of the event of 21 23 march 1985 and 3 an investigation of the flow structure and force balance within the cold dome the climatology reveals cold air damming is a year round phenomenon in the southern appalachians with the most frequent prolonged and intense events occurring in winter particularly december and march when three five events per month can be expected cold air damming is least frequent and intense in july the synoptic case study reveals that cold air damming is critically dependent upon the configuration of the synoptic scale flow the cold dome can be identified by a u shaped ridge trough in the sea level isobar thermal patterns and the 930 mb height temperature fields representative of conditions at the base of the inversion overlying the cold dome differential horizontal and vertical thermal advection as well as adiabatic and evaporative cooling are r

characterizing biases in mountain snow accumulation from global data sets author s wrzesien melissa l pavelsky tamlin m durand michael t dozier jeff lundquist jessica d

geological fullerenes review and analysis abstract fullerenes have been reported from numerous terrestrial and meteoritic sources but only at low concentrations the occurrences are associated with localized energetic events such as lightning impacts of extraterrestrial objects and wildfires great interest has also been generated by a series of papers that report noble gases with anomalous isotopic compositions encapsulated within fullerenes in spite of all of the published work many unresolved questions remain about the identity and formation of fullerenes in geological environments

testing for fullerenes in geologic materials oklo carbonaceous substances karelian shungites sudbury black tuff comment and reply the presence of low concentrations of fullerenes has been reported from numerous terrestrial and meteoritic sources buseck 2002 1 in a recent paper mossman et al 2003 2 present mass spectra of carbonaceous substances using laser desorption ionization ldi and high resolution electron

air temperature distribution and energy balance modelling of a debris covered glacier near surface air temperature is an important determinant of the surface energy balance of glaciers and is often represented by a constant linear temperature gradients tgs in models spatiotemporal variability in 2 m air temperature was measured across the debris covered miage glacier italy over an 89 d period during the 2014 ablation season using a network of 19 stations air temperature was found to be strongly dependent upon elevation for most stations even under varying meteorological conditions and at different times of day and its spatial variability was well explained by a locally derived mean linear tg mg tg of 0 0088 c m 1 however local temperature depressions occurred over areas of very thin or patchy debris cover the mg tg together with other air tgs extrapolated from both on and off glacier sites were applied in a distributed energy balance model compared with piecewise air temperature extrapolation from all on glacier stations modelled ablation using the mg tg increased by 4 using the environmental lapse rate ice melt under thick debris was relatively insensitive to air temperature while the effects of different temperature extrapolation methods were strongest at high elevation sites of thin and patchy debris cover

evidence for fullerenes in solid bitumen from pillow lavas of proterozoic age from mitov bohemian massif czech republic abstract andesitic pillow lavas containing biogenic solid bitumen sb are a constituent of a neoproterozoic volcanosedimentary sequence tepla barrandian unit bohemian massif in the mitov area of the czech republic a black shale formation that is crosscut by these andesitic basalts is 565 ma old carbon disulfide extracts of two powdered samples of sb contain 0 2 and 0 3 ppm of c 60 respectively as determined by high pressure liquid chromatography the peak assignment based on retention time is fully supported by high resolution electron ionization mass spectrometry ei ms no c 70 was detected nor was c 60 found in two other sb samples from this locality other investigated carbonaceous samples from bohemia coals and anthracites of upper paleozoic age and anthraxolite graphitoids and graphite of upper proterozoic age did not contain fullerenes at concentrations above the detection limit of 0 01 ppm the absence of c 60 in these samples was confirmed by ei ms the proposed mechanism of fullerene formation involves a primary algal phase generation of a hydrocarbonaceous mixture in the course of thermal evolution of the sedimentary series and their high temperature transformation related to the extrusion of basalt an important feature for fullerene conservation was the enclosure of fullerenes in sb with a structure similar to glasslike carbon where the fullerene was protected against oxidation

daily air temperature estimation on glacier surfaces in the tibetan plateau using modis lst data the moderate resolution imaging spectroradiometer modis land surface temperature lst data have been widely used for air temperature estimation in mountainous regions where station observations are sparse however the performance of modis lst in high elevation glacierized areas remains unclear this study investigates air temperature estimation in glacierized areas based on ground observations at four glaciers across the tibetan plateau before being used to estimate the air temperature modis lst data are evaluated at two of the glaciers which indicates that modis night time lst is more reliable than modis daytime lst data then linear models based on each of the individual modis lst products from two platforms terra and aqua and two overpasses night time and daytime are built to estimate daily mean minimum and maximum air temperatures in glacierized areas regional glacier surface rgs models mean mean square differences 3 3 3 0 and 4 8 c for daily mean minimum and maximum air temperatures respectively show higher accuracy than local non glacier surface models mean root mean square differences 4 2 4 7 and 5 7 c in addition the rgs models based on modis night time lst perform better to estimate daily mean minimum and maximum air temperatures than using temperature lapse rate derived from local stations

black carbon in soils and sediments analysis distribution implications and current challenges this review highlights the ubiquity of black carbon bc produced by incomplete combustion of plant material and fossil fuels in peats soils and lacustrine and marine sediments we examine various definitions and analytical approaches and seek to provide a common language bc represents a continuum from partly charred material to graphite and soot particles with no general agreement on clear cut boundaries formation of bc can occur in two fundamentally different ways volatiles recondense to highly graphitized soot bc whereas the solid residues form char bc both forms of bc are relatively inert and are distributed globally by water and wind via fluvial and atmospheric transport we summarize chronologically the ubiquity of bc in soils and sediments since devonian times differentiating between bc from vegetation fires and from fossil fuel combustion bc has important implications for various biological geochemical and environmental processes as examples bc may represent a significant sink in the global carbon cycle affect the earth s radiative heat balance be a useful tracer for earth s fire history build up a significant fraction of carbon buried in soils and sediments and carry organic pollutants on land bc seems to be abundant in dark colored soils affected by frequent vegetation burning and fossil fuel combustion thus probably contributing to the highly stable aromatic components of soil organic matter we discuss challenges for future research despite the great importance of bc only limited progress has been made in calibrating analytical techniques progress in the quantification of bc is likely to come from systematic intercomparison using bcs from different sources and in different natural matrices bc identification could benefit from isotopic and spectroscopic techniques applied at the bulk and molecular levels the key to estimating bc stocks in soils and sediments is an understanding of the processes involved in bc degradation on a molecular level a promising approach would be the combination of short term laboratory experiments and long term field trials

search for extractable fullerenes in clays from the cretaceous tertiary boundary of the woodside creek and flaxbourne river sites new zealand abstract when fullerenes were first discovered to form spontaneously in condensing carbon vapors kroto et al 1985 it was suggested that they might be widely distributed in the universe searches for fullerenes in meteorites see devries et al 1993 were unsuccessful but c 60 and c 70 were reported to occur on earth in samples of shungite a meta anthracite from a deposit near shunga russia buseck et al 1992 and in fulgurite a substance formed when lightning strikes certain soils or rocks daly et al 1993 the occurrence of fullerenes in shungite is particularly surprising since fullerene synthesis in the laboratory has always involved gas phase chemistry at temperatures over 1000 c such conditions may be attained during lightning strikes but shungite is believed to have formed from carbonaceous material creeping into fissures of a precambrian rock which metamorphosed under extreme pressures if the original carbonaceous material did not already contain fullerenes perhaps from wildfires they must have formed during the metamorphism by as yet unknown solid or liquid phase mechanisms

mineral templated growth of natural graphite films abstract organic material in sediments is progressively altered during diagenesis and metamorphism leading to the formation of kerogen and ultimately crystalline graphite bulk carbonaceous material in metamorphic terrains typically has attained an overall degree of structural order that is in line with peak metamorphic temperature on a micron to nano scale however carbonaceous material can display strong structural variation the main factor that drives this variation is the chemical and molecular heterogeneity of the precursor biologic material specific conditions during metamorphism however can also play a role in shaping the microstructure of carbonaceous material here we describe the structural variation of carbonaceous material in rocks of the 2 0 ga zaonega formation karelia russia raman spectroscopy indicates that bulk carbonaceous matter in these rocks has experienced peak temperatures between 350 and 400 c consistent with greenschist facies metamorphism on a nano scale however a strong structural heterogeneity is observed transmission electron microscopy tem reveals the occurrence of thin films of highly ordered graphitic carbon at mineral surfaces these graphite films consisting of 20 100 individual layers completely envelop quartz crystals and occur on specific crystal surfaces of chlorite it is proposed that minerals can act as templates for the parallel ordering of carbon crystallites causing enhanced graphitization within narrow zones at mineral surfaces alternatively oriented organic precursor molecules could have been adsorbed onto charged mineral surfaces leading to thin graphitic films during later metamorphic heating episodes overall the presented observations demonstrate that mineral surfaces can initiate and accelerate localized graphitization of sedimentary organic material during metamorphism and therefore cause distinct nano scale variation in structural order

testing for fullerenes in geologic materials oklo carbonaceous substances karelian shungites sudbury black tuff fullerenes have been reported from diverse geologic environments since their discovery in shungite from karelian russia our investigation is prompted by the presence of onionskin like structures in some carbonaceous substances associated with the fossil nuclear fission reactors of oklo gabon the same series of extractions and the same instrumental techniques laser desorption ionization and high resolution mass spectroscopy electron impact mass spectroscopy were employed to test for fullerenes in samples from three different localities two sites containing putative fullerenes sudbury basin and russian karelia and one new location oklo gabon we confirm the presence of fullerenes c 6 0 and c 7 0 in the black tuff of the onaping formation impact breccia in the sudbury basin but we find no evidence of fullerenes in shungite samples from various locations in russian karelia analysis of carbonaceous substances associated with the natural nuclear fission reactors of oklo yields no definitive signals for fullerenes if fullerenes were produced during sustained nuclear fission at oklo then they are present below the detection limit 100 fmol or they have destabilized since formation contrary to some expectations geologic occurrences of fullerenes are not commonplace

stacked late devonian lowstand shorelines and their relation to tectonic subsidence at the cordilleran hingeline western utah abstract the upper devonian lower famennian cove fort quartzite and associated strata of western utah comprise three stratigraphic sequences each containing a thick as much as 65 m lowstand systems tract coarse grained shoreface quartz arenite and lagoonal dolomicrite of the lowstand systems tracts display the following features characteristic of forced regression 1 they contain coarse grained proximal shoreline deposits that overlie an erosional surface sequence bounding unconformity cut into fine grained distal marine carbonate facies 2 they lie seaward of a zone of sediment bypass and are spatially detached and separated from the previous highstand shoreface 3 they are confined geographically to a relatively narrow zone less than 30 km wide 4 they are onlapped and overlain by transgressive systems tract deposits consisting of deep subtidal carbonates west range limestone and 5 landward of the lowstand shoreline pinch out the sequence bounding unconformity beneath them merges with a transgressive surface of erosion above them a thick wedge of siliciclastic forced regression deposits is present at the base of each depositional sequence the stratigraphic position of each wedge above the basal sequence boundary was controlled by eustatic sea level fall the forced regression deposits are geographically restricted to a narrow strike belt along the eastern margin of the pilot basin which coincides with the trace of the cordilleran hingeline a zone of crustal discontinuity the geographic confinement and unusual stratal thickness of barrier bar complexes in the lowstand systems tract as well as the stratigraphic stacking of the forced regression deposits were controlled by flexurally induced high subsidence rates focused at the cordilleran hingeline

variability of air temperature over a debris covered glacier in the nepalese himalaya estimates of melt from debris covered glaciers require distributed estimates of meteorological variables and air temperature in particular meteorological data are scarce for this environment and spatial variability of temperature over debris is poorly understood based on multiple measurements of air and surface temperature from three ablation seasons 2012 14 we investigate the variability of temperature over lirung glacier nepal in order to reveal how air temperature is affected by the debris cover and improve ways to extrapolate it we investigate how much on glacier temperature deviates from that predicted from a valley lapse rate lr analyse on glacier lrs and test regression models of air temperature and surface temperature air temperature over the debris covered glacier tongue is much higher than what a valley lr would prescribe so an extrapolation from off glacier stations is not applicable an on glacier lr is clearly defined at night with strong correlation but not during the day when the warming debris disrupts the elevation control an alternative to derive daytime air temperature is to use a relationship between air and surface temperature as previously suggested we find strong variability during daytime that should be accounted for if these regressions are used for temperature extrapolation

the climatology of small scale orographic precipitation over the olympic mountains patterns and processes the climatology of small scale patterns of mountain precipitation is poorly constrained yet important for applications ranging from natural hazard assessment to understanding the geologic evolution of mountain ranges synthesizing four rainy seasons of high resolution precipitation observations and mesoscale model output from the penn state ncar mm5 reveals a persistent small scale pattern of precipitation over the 10 km wide 800 m high ridges and valleys of the western olympic mountains washington state usa this pattern is characterized by a 50 70 excess accumulation over the ridge crests relative to the adjacent valleys in the annual mean while the model shows excellent skill in simulating these patterns at seasonal time scales major errors exist for individual storms investigation of a range of storm events has revealed the following mechanism for the climatological pattern regions of enhanced condensation of cloud water are produced by ascent in stable flow over the windward slopes of major ridges synoptically generated precipitation grows by collection within these clouds leading to enhanced precipitation which is advected by the prevailing winds instances of atypical patterns of precipitation suggest that under certain conditions during periods with a low freezing level or convective cells fundamental changes in small scale patterns may occur however case studies and composite analysis suggest that departures from the pattern of ridge top enhancement are rare the basic patterns and processes appear robust to changes in temperature winds and background rainfall rates copyright 2008 royal meteorological society

air temperature variability in a high elevation himalayan catchment air temperature is a key control of processes affecting snow and glaciers in high elevation catchments including melt snowfall and sublimation it is therefore a key input variable to models of land surface atmosphere interaction despite this importance its spatial variability is poorly understood and simple assumptions are made to extrapolate it from point observations to the catchment scale we use a dataset of 2 75 years of air temperature measurements from may 2012 to november 2014 at a network of up to 27 locations in the langtang river nepal catchment to investigate air temperature seasonality and consistency between years we use observations from high elevations and from the easternmost section of the basin to corroborate previous findings of shallow lapse rates seasonal variability is strong with shallowest lapse rates during the monsoon season diurnal variability is also strong and should be taken into account since processes such as melt have a pronounced diurnal variability use of seasonal lapse rates seems crucial for glacio hydrological modelling but seasonal lapse rates seem stable over the 2 3 years investigated lateral variability at transects across valley is high and dominated by aspect with south facing sites being warmer than north facing sites and deviations from the fitted lapse rates of up to several degrees local factors e g topographic shading can reduce or enhance this effect the interplay of radiation aspect and elevation should be further investigated with high elevation transects

sensitivities of the equilibrium line altitude to temperature and precipitation changes along the andes abstract equilibrium line altitudes elas of alpine glaciers are sensitive indicators of climate change and have been commonly used to reconstruct paleoclimates at different temporal and spatial scales however accurate interpretations of ela fluctuations rely on a quantitative understanding of the sensitivity of elas to changes in climate we applied a full surface energy and mass balance model to quantify ela sensitivity to temperature and precipitation changes across the range of climate conditions found in the andes model results show that ela response has a strong spatial variability across the glaciated regions of south america this spatial variability correlates with the distribution of the present day mean climate conditions observed along the andes we find that elas respond linearly to changes in temperature with the magnitude of the response being prescribed by the local lapse rates ela sensitivities to precipitation changes are nearly linear and are inversely correlated with the emissivity of the atmosphere temperature sensitivities are greatest in the inner tropics precipitation becomes more important in the subtropics and northernmost mid latitudes these results can be considered an important step towards developing a framework for understanding past episodes of glacial fluctuations and ultimately for predicting glacier response to future climate changes

multitemporal snow cover mapping in mountainous terrain for landsat climate data record development abstract a multitemporal method to map snow cover in mountainous terrain is proposed to guide landsat climate data record cdr development the landsat image archive including mss tm and etm imagery was used to construct a prototype landsat snow cover cdr for the interior northwestern united states landsat snow cover cdrs are designed to capture snow covered area sca variability at discrete bi monthly intervals that correspond to ground based snow telemetry snotel snow water equivalent swe measurements the june 1 bi monthly interval was selected for initial cdr development and was based on peak snowmelt timing for this mountainous region fifty four landsat images from 1975 to 2011 were pre processed that included image registration top of the atmosphere toa reflectance conversion cloud and shadow masking and topographic normalization snow covered pixels were retrieved using the normalized difference snow index ndsi and unsupervised classification and pixels having greater less than 50 snow cover were classified presence absence a normalized sca equation was derived to independently estimate sca given missing image coverage and cloud shadow contamination relative frequency maps of missing pixels were assembled to assess whether systematic biases were embedded within this landsat cdr our results suggest that it is possible to confidently estimate historical bi monthly sca from partially cloudy landsat images this multitemporal method is intended to guide landsat cdr development for freshwater scarce regions of the western us to monitor climate driven changes in mountain snowpack extent

a hot and high eocene sierra nevada despite broad interest in determining the topographic and climatic histories of mountain ranges the evolution of california s sierra nevada remains actively debated prior stable isotope based studies of the sierra nevada have relied primarily on hydrogen isotopes in kaolinite hydrated volcanic glass and leaf n alkanes here we reconstruct the temperature and elevation of the early eocene sierra nevada using the oxygen isotope composition of kaolinitized granite clasts from the ancestral yuba and american rivers that drained the windward pacific flank of the sierra nevada first we evaluated the possible contributions of hydrogen isotope exchange in kaolinite by direct comparison with oxygen isotope measurements next we utilized differences in the hydrogen and oxygen isotope fractionation in kaolinite to constrain early eocene midlatitude weathering temperatures oxygen isotope geochemistry of in situ kaolinites indicates upstream eastward depletion of 18o in the northern sierra nevada the 18o values ranging from 11 4 to 14 4 at the easternmost localities correspond to paleoelevations as high as 2400 m when simulating the orographic precipitation of moisture from a pacific source using eocene boundary conditions this result is consistent with prior hydrogen isotope studies of the northern sierra but oxygen isotope based paleoelevation estimates are systematically 500 1000 m higher than those from hydrogen based estimates from the same samples kaolinite geothermometry from 16 samples produced early eocene weathering temperatures of 13 0 36 7 c with an average of 23 2 6 4 c 1 these kaolinite temperature reconstructions are in general agreement with paleofloral and geochemical constraints from eocene california localities and climate model simulations our results confirm prior hydrogen isotope based paleoelevation estimates and further substantiate the existence of a hot and high eocene sierra nevada