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Seasonal snow-derived water is a critical component of the water supply in the mountains and downstream regions, and the accurate characterization of available water in the form of snow-water-equivalent (SWE), peak SWE, and snowmelt onset are essential inputs for water management efforts. Arising from recent advancements in artificial intelligence (AI) and machine learning (ML), we introduce a large-scale ML SWE model leveraging publicly available data sources and open-source software. The model demonstrates the application of a limited feature space in a relatively simple ML architecture without the need for process-based formulations to effectively estimate spatially continuous SWE at a daily temporal resolution. Beginning with in situ SWE measurements (i.e., SNOTEL), lidar-derived terrain features, and temporal variables, we employ localized feature engineering and optimization via gradient-boosting decision trees to identify regionally unique drivers of snowpack dynamics and use the optimal features to train regionally independent artificial neural networks to estimate regional SWE at a 1 km spatial resolution. The model results yield respectable skill in reconstructed 1 km gridded SWE magnitudes in a hindcast simulation of the 2019 water year that is independent of the training and testing data. Comparing model estimates to over 6200 observations, the model demonstrates a weighted RMSE of 15.4 cm, Kling-Gupta Efficiency metric of 0.86, and a percent bias of 0.71% across 23 snow-influenced regions in the western U.S. The model simulation produces peak SWE estimates within 10 cm for twenty of the twenty-three regions, demonstrating capability in effectively capturing regional snow accumulation processes. The demonstration of low-error ML workflows capable of providing near-real-time, spatially continuous SWE estimates at a high spatial resolution provides proof-of-concept and a foundation to effectively update snow state variables that drive water supply forecasts in snow-dominated regions. • A new Machine Learning-based SWE estimation model for the Western United States. • Utilization of open-source tools and up-to-date in-situ observations to estimate SWE. • Reconstructed SWE magnitudes exhibit respectable skill in a hindcast simulation. • Output may serve as a supplemental state-of-snowpack input to hydrologic models. [ABSTRACT FROM AUTHOR]

Abstract: Ecomorphodynamic feedbacks play an important role in the susceptibility and response of barrier islands to disturbance by overwash. Dune-building grasses, like Ammophila breviligulata, can help to restore areas of high relief after overwash events (i.e., resist disturbance). If overwash recurs before dunes have reestablished, however, overwash-adapted “maintainer” species, like Spartina patens (upright variety), may preferentially survive. Maintainer species help to preserve low, flat topography, thereby increasing the likelihood of future overwash (i.e., reinforcing disturbance). Under frequent disturbance conditions, this positive feedback may lead to overwash persistence. We explore the potential influence of the maintainer feedback on two morphologically distinct barrier islands in the Virginia Coast Reserve (VCR), located in the Mid-Atlantic Bight of the U.S. East Coast. Combined topographic and vegetation surveys show that on Hog Island (high-relief, rotating), where dunes dominated by A. breviligulata are ubiquitous, overwash zones are currently limited in extent and related to beach width rather than dominance by S. patens. Historical aerial photos and stratigraphic evidence (ground-penetrating radar, cores) indicate that gradual recovery has taken place following overwash events on Hog Island, except where the beach is narrow and eroding. Conversely, on Metompkin Island (low-relief, transgressing), overwash is widespread and dominated by S. patens, particularly along the rapidly migrating northern half of the island, where shell armoring is also common. Overwash has generally been more prevalent and persistent here than on Hog Island. We present a new conceptual model of the response of barrier islands to disturbance incorporating ecological and physical processes. Our findings suggest that in barrier systems where both dune-building grasses and overwash-adapted maintainer species are common (like the VCR), the maintainer feedback is likely to be a more important dynamic on islands already susceptible to frequent disturbance because of physical factors. The maintainer feedback, therefore, has the potential to accelerate large-scale shifts from dune-dominated to overwash-dominated barrier morphologies as the effects of climate change (increased storm intensity, sea level rise) cause overwash to become more frequent. [Copyright &y& Elsevier]

Abstract: Coastal barriers are particularly susceptible to the effects of accelerated sea-level rise and intense storms. Over centennial scales, barriers are maintained via overtopping during storms, which causes deposition of washover fans on their landward sides. Understanding barrier evolution under modern conditions can help evaluate the likelihood of future barrier stability. This study examines three washover fans on the undeveloped south shore of Martha's Vineyard using a suite of vibracores, ground penetrating radar, high resolution dGPS, and LiDAR data. From these data, the volumes of the deposits were determined and range from 2.1 to 2.4×104 m3. Two of these overwash events occurred during Hurricane Bob in 1991. The water levels produced by this storm have a calculated return interval of ~28years, implying an onshore sediment flux of 2.4–3.4m3/m/yr. The third washover was deposited by a nor'easter in January 1997, which has a water level return interval of ~6years, suggesting a flux of 8.5m3/m/yr. These onshore fluxes are smaller than the erosional flux of sediment resulting from shoreline retreat, suggesting that the barrier is not in long-term equilibrium, a result supported by the thinning of the barrier in recent years. [Copyright &y& Elsevier]

Abstract: The particle-reactive radionuclides 7Be and 210Pb have been employed extensively as tracers and chronometers for a variety of aquatic and terrestrial processes. Both radionuclides are delivered to the Earth''s surface from the atmosphere, and in order to use them effectively as natural tracers, an understanding of variations in atmospheric fluxes of these radionuclides due to latitudinal differences and storm events is required. The monthly atmospheric fluxes of 7Be and 210Pb, measured from April-2008 to December-2009 at Stony Brook, NY, ranged from 67 to 385 Bq m−2 and 6.7 to 16.7 Bq m−2, respectively. Composite annual atmospheric fluxes over the sampling period were 3110 ± 1200 Bq m−2 y−1 for 7Be and 146 ± 50 Bq m−2 y−1 for 210Pb and were similar to geographically comparable sites. The monthly atmospheric fluxes of 7Be and 210Pb were significantly correlated with rainfall. The 7Be/210Pb ratio in the monthly samples varied seasonally, with values of ∼10–11 during the winter months and ∼20–28 during the spring – fall. The pattern of seasonal variation in 7Be fluxes and 7Be/210Pb ratios is most consistent with that observed in surface air at continental sites in which more frequent deep convective storms occur during the summer and therefore result in an increased transport of 7Be from the upper troposphere to the Earth''s surface. An additional factor may be that the winds at Stony Brook were dominantly from the northwest during the winter of 2009 and so were characterized by low 7Be/210Pb ratios while in the spring, winds from the southwest brought marine air with higher 7Be/210Pb ratios to the sampling site. Fluxes of 7Be and 210Pb also were measured over two long (16–24 h) and two short (∼1 h) intense periods of rainfall in June and July 2009. Fluxes of 7Be and 210Pb continued throughout the short events, but the two radionuclides showed different patterns during the long events. While the entirety of the 210Pb flux accumulated during the first ∼1 h, 7Be continued to be accumulated over the course of both long events. The 7Be/210Pb ratio ranged from 20 to ∼300 during the events and, in general, was considerably greater than the ratios measured in the monthly samples. Radar image snapshots taken during the events show cloud heights of 7–10.5 km, and the 7Be/210Pb ratios measured in the precipitation are consistent with previous model estimates of 7Be/210Pb ratios in aerosols at altitudes of 5–10 km (latitude 40°N). The data suggest that 210Pb can be effectively stripped from the lower troposphere early in a rainfall event, but intense convective mixing and scavenging of 7Be from the upper troposphere results in a continuous flux of 7Be and elevated 7Be/210Pb ratios as the event progresses. [Copyright &y& Elsevier]

Abstract: Since the 1970s Lunar Laser Ranging (LLR) to the Apollo Cube Corner Retroreflector (CCR) arrays (developed by the University of Maryland, UMD) have supplied significant tests of General Relativity: possible changes in the gravitational constant, gravitational self-energy, weak equivalence principle, geodetic precession, inverse-square force-law. LLR has also provided significant information on the composition and origin of the Moon. This is the only Apollo experiment still in operation. In the 1970s Apollo LLR arrays contributed a negligible fraction of the ranging error budget. Since the ranging capabilities of ground stations improved by more than two orders of magnitude, now, because of the lunar librations, Apollo CCR arrays dominate the error budget. With the project MoonLIGHT (Moon Laser Instrumentation for General relativity High-accuracy Tests), in 2006 INFN-LNF joined UMD in the development and test of a new-generation LLR payload made by a single, large CCR (100mm diameter) unaffected by librations. In particular, INFN-LNF built and is operating a new experimental apparatus (Satellite/lunar laser ranging Characterization Facility, SCF) and created a new industry-standard test procedure (SCF-Test) to characterize and model the detailed thermal behavior and the optical performance of CCRs in laboratory-simulated space conditions, for industrial and scientific applications. Our key experimental innovation is the concurrent measurement and modeling of the optical Far Field Diffraction Pattern (FFDP) and the temperature distribution of retroreflector payloads under thermal conditions produced with a solar simulator. The apparatus includes infrared cameras for non-invasive thermometry, thermal control and real-time payload movement to simulate satellite orientation on orbit with respect to solar illumination and laser interrogation beams. These capabilities provide: unique pre-launch performance validation of the space segment of LLR/SLR (Satellite Laser Ranging); retroreflector design optimization to maximize ranging efficiency and signal-to-noise conditions in daylight. Results of the SCF-Test of our CCR payload will be presented. Negotiations are underway to propose our payload and SCF-Test services for precision gravity and lunar science measurements with next robotic lunar landing missions. We will describe the addition of the CCR optical Wavefront Fizeau Interferogram (WFI) concurrently to FFDP/temperature measurements in the framework of an ASI-INFN project, ETRUSCO-2. The main goals of the latter are: development of a standard GNSS (Global Navigation Satellite System) laser Retroreflector Array; a second SCF; SCF-Test of Galileo, GPS and other ‘as-built’ GNSS retroreflector payloads. Results on analysis of Apollo LLR data and search of new gravitational physics with LLR, Mercury Radar Ranging will be presented. [Copyright &y& Elsevier]

Background: Health is firmly on the economic radar. It is big business. In 2009, the proportion of the Gross Domestic Product spent on health care varied between 6.4% in Mexico and 17.4% in the U.S., with the UK at 9.8% and Germany, Switzerland and Canada ∼11%. These are considerable amounts of money and they are growing. With all projections pointing to a growth in the numbers of older people, the pressure on budgets will only increase. In this paper we will consider the role of dementia in this. Methods: Demographic and economic data were combined and policy implications developed. Results: The costs of dementia dwarf those of the illnesses that are currently prioritized at a national and international level such as HIV, cancer, heart disease, stroke and diabetes. Based on simple demographics, the costs of dementia are set to increase by 85% by 2030, with developing countries bearing an increasing share of the economic burden. Conclusions: The data suggest that dementia is a clear and present economic challenge for the world from the macro level down to the individual. Before the crisis, governmental structural primary deficits were generally improving and this would have given time and resource to meet the challenges of ageing in general and dementia in particular. However, increasing government debt over the past 3 years has had the effect of our needing to implement reforms to contain the risks to sovereign budgets sooner rather than later. This is not an issue that can be ignored. Inaction will only lead to further debt accumulation in the medium term and the death of systems of care in the long term. Across the developed world, the main long-term fiscal challenges come from health care costs, and dementia is a major driver of those costs. There is a need for budgetary consolidation and pension reform more generally. But, given that dementia is the highest ticket health and social care item that we have, making up 60% of long term care spending according to some estimates, then targeted investment in early intervention and in research (into causes, cure and care) are likely to be of major value in personal, societal, political, and economic terms. [Copyright &y& Elsevier]

Abstract: Snow Water Equivalent (SWE) is a crucial parameter in the study of climatology and hydrology. Active microwave remote sensing is one of the most promising techniques for estimating the distribution of SWE at high spatial resolutions in large areas. Development of reliable and accurate inversion techniques to recover SWE is one of the most important tasks in current microwave researches. However, a number of snow pack properties, including snow density, particle size, crystal shape, stratification, ground surface roughness and soil moisture, affect the microwave scattering signals and need to be properly modeled and exploited. In this paper, we developed a multi-layer, multi-scattering model for dry snow based on recent theoretical advances in snow and surface modeling. In the proposed multi-layer model, Matrix Doubling method is used to account for scattering from each snow layer; and Advanced Integral Equation Model (AIEM) is incorporated into the model to describe surface scattering. Comparisons were made between the model predictions and field observations from NASA Cold Land Processes Field Experiment (CLPX) during Third Intensive Observation Period (IOP3) and SARALPS-2007 field experiment supported by ESA. The results indicated that model predictions were in good agreement with field observations. With the confirmed confidence, the analyses on multiple scattering, scatterer shape, and snow stratification effects were further made based on the model simulations. Furthermore, a parameterized snow backscattering model with a simple form and high computational efficiency was developed using a database generated by the multiple-scattering model. For a wide range of snow and soil properties, this parameterized model agrees well with the multiple-scattering model, with the root mean square error 0.20dB, 0.24dB and 0.43dB for VV, HH and VH polarizations, respectively. This simplified model can be useful for the development of SWE retrieval algorithm and for fast simulations of radar signals over snow cover in land data assimilation systems. [Copyright &y& Elsevier]

Abstract: A principal method for studying past hydroclimatic change is the reconstruction of paleo-lake levels. Here, we provide high-resolution lake-level records from New Long Pond and Rocky Pond in southeastern Massachusetts, which each contain evidence for multiple, sub-centennial-to-millennial scale low stands during the transition between the Late Pleistocene (15.0ka) and Middle Holocene (ca 7.0ka). Data from New Long Pond also demonstrate sedimentary evidence for a drop in water levels in the early to mid AD 20th century, when long-term trends in instrumental data show lower-than-average precipitation in the northeastern United States. Local data show the most precipitous declines in precipitation and groundwater levels are concurrent with the most severe drought in the AD 1960s, which occurred during a period of low sea-surface temperatures in the western North Atlantic. Ground penetrating radar and sediment core data indicate five intervals with numerous paleo-shoreline deposits between ca 15.0 and 7.0ka, similar to the layer deposited in the AD 1960s. Many of the intervals of low lake levels coincide with proposed meltwater release events or abrupt climate oscillations in the circum North Atlantic. For example, we document at least three low stands during the Younger Dryas (12.9–11.6ka) and in association with the “9.2” and “8.2”ka events. The combined evidence of (1) concurrent paleo-droughts in southeastern New England with documented North Atlantic abrupt cooling events and (2) recent drought with the modern association of low sea-surface temperatures indicates that freshening and cooling of the western North Atlantic is a viable mechanism for decreasing moisture within the region. Large-scale changes in seasonality and ice sheet extent also may have increased the susceptibility of the northeast to dry conditions triggered by changes in the North Atlantic. [Copyright &y& Elsevier]

Often when various estuarine benthic indices disagree in their assessments of benthic condition, they are reflecting different aspects of benthic condition. We describe a process to screen indices for associations and, after identifying candidate metrics, evaluate metrics individually against the indices. We utilize radar plots as a multi-metric visualization tool, and conditional probability plots and receiver operating characteristic curves to evaluate associations seen in the plots. We investigated differences in two indices, the US EPA Environmental Monitoring and Assessment Program’s benthic index for the Virginian Province and the New York Harbor benthic index of biotic integrity using data collected in New York Harbor and evaluated overall agreement of the indices and associations between each index and measures of habitat and sediment contamination. The indices agreed in approximately 78% of the cases. The New York Harbor benthic index of biotic integrity showed stronger associations with sediment metal contamination and grain size. [Copyright &y& Elsevier]

Abstract: A conceptual design for a southeast United States regional coastal ocean observing system (RCOOS) is built upon a partnership between institutions of the region and among elements of the academic, government and private sectors. This design envisions support of a broad range of applications (e.g., marine operations, natural hazards, and ecosystem-based management) through the routine operation of predictive models that utilize the system observations to ensure their validity. A distributed information management system enables information flow, and a centralized information hub serves to aggregate information regionally and distribute it as needed. A variety of observing assets are needed to satisfy model requirements. An initial distribution of assets is proposed that recognizes the physical structure and forcing in the southeast U.S. coastal ocean. In-situ data collection includes moorings, profilers and gliders to provide 3D, time-dependent sampling, HF radar and surface drifters for synoptic sampling of surface currents, and satellite remote sensing of surface ocean properties. Nested model systems are required to properly represent ocean conditions from the outer edge of the EEZ to the watersheds. An effective RCOOS will depend upon a vital “National Backbone” (federally supported) system of in situ and satellite observations, model products, and data management. This dependence highlights the needs for a clear definition of the National Backbone components and a Concept of Operations (CONOPS) that defines the roles, functions and interactions of regional and federal components of the integrated system. A preliminary CONOPS is offered for the Southeast (SE) RCOOS. Thorough system testing is advocated using a combination of application-specific and process-oriented experiments. Estimates of costs and personnel required as initial components of the SE RCOOS are included. Initial thoughts on the Research and Development program required to support the RCOOS are also outlined. [Copyright &y& Elsevier]

Abstract: Online tools, such as those pioneered by Google Earth (GE), are changing the way in which scientists and the general public interact with three-dimensional geospatial data in a virtual environment. However, while GE provides a number of features to facilitate geospatial data visualization, there is currently no readily available method for rendering vertical geospatial data derived from Earth—viewing remote sensing satellites as an orbit curtain seen from above. Here, a solution (one of many possible) is demonstrated to render vertical profiles of atmospheric data from the A-Train satellite formation in GE, using as a proof-of-concept data from one of the instruments—the NASA CloudSat satellite. CloudSat carries a nadir-viewing Cloud Profiling Radar that produces data revealing the vertical distribution of cloud characteristics along the satellite track. These data are first rendered into a long vertical image for a user-selected spatial range through the NASA Goddard Interactive Online Visualization ANd aNalysis Infrastructure (Giovanni) system (http://giovanni.gsfc.nasa.gov/). The vertical image is then chopped into small slices representing 15s of satellite time (∼103km long ground distance). Each small piece, as a texture, is fed into a generalized COLLAborative Design Activity (COLLADA) three-dimensional (3-D) model. Using the satellite orbit coordinates, the repeated 15s “3-D model slices” are spliced together to form a vertical “curtain” image in Keyhole Markup Language (KML) format. Each model slice is geolocated along the CloudSat orbit path based on its size, scale and angle with the longitude line that are precisely calculated on the fly. The resulting vertical cloud data can be viewed in GE, either transparently or opaquely, superimposed above the Earth''s surface with an exaggerated vertical scale. Since CloudSat is just a part of the A-Train formation, the full utility of this tool can be explored within the context of the A-Train Data Depot (ATDD, http://disc.gsfc.nasa.gov/atdd/) and the corresponding Giovanni instance (http://disc1.sci.gsfc.nasa.gov/daac-bin/G3/gui.cgi?instance_id=atrain). The latter portal allows scientists and the general public to access and visualize complex A-Train datasets without having to delve into data formats specific to a given mission. [Copyright &y& Elsevier]

Abstract: Convective systems are tracked for two summer months over the continental USA and their properties at different stages of life are investigated in terms of Cloud to Ground (CG) lightning flashes, cloud kinematics, and precipitation. The study employs lightning data from the National Lightning Detection Network (NLDN) along with 1/2-hourly satellite Infrared observations, and hourly rainfall accumulation fields from the nationwide WSR-88D radar network. Results show strong dependence of the amount of CG lightning flashes with the stage of the storm''s life cycle. The highest number of CG lightning flashes and highest area expansion rates are also seen to be during the growth stage of the systems. The stronger the lightning density, or cloud top area expansion rate, of the storms at their initiation stage is the longer is shown to be their life duration. The average rainfall yield per flash in the growing, mature and dissipation stages of storms with duration greater than 4 h is 4.7, 12.5 and 8.5 107 kg, respectively. The temporal evolution of the storms'' area and CG flash rate are shown to correlate well with the evolution of rainfall parameters, such as storm''s rainfall yield (m3), conditional mean rainfall rate, and the fraction of rain area. The consideration of the kinematics and CG lightning flashes of convective systems and the knowledge of their life cycle stage demonstrate a potential for drawing information useful in rain rate retrievals and their variability. [Copyright &y& Elsevier]

Abstract: Long-term hydrocarbon microseepages develop diverse arrays of chemical and mineralogical changes in rocks and soils. Alterations that are reported to have affected the Wingate Sandstone, Lisbon Valley, Utah, include bleaching of red beds, precipitation of high limonite and carbonate concentrations, anomalous weathering patterns, and high clay content. To investigate sandstone color alteration patterns, spectroscopy, ASTER multispectral remote sensing and Synthetic Aperture Radar (SAR) data were used as well as geochemical analyses of selected samples. Using ASTER satellite images and SAR data, the altered areas of the Wingate Sandstone were identified and mapped at the northwest and southwest part of the Lisbon Valley anticline. Based on sandstone color alteration patterns three different zones were identified in the Wingate Sandstone; the southwest zone is the most altered, the middle part is unaltered, and the northwest part shows minor alteration. Spectroscopy and thin section studies revealed higher content of clay minerals in altered than in unaltered zones. Major elemental concentrations suggest removal of iron cement and addition of calcite during diagenesis. Trace elemental concentrations in selected altered sandstone samples are characteristic of geochemical halos forming over oil fields. The methodology being developed in this work can provide a completely new technique for petroleum exploration in remote regions of the world where field work is difficult. [Copyright &y& Elsevier]

Abstract: Remote sensing with sensors mounted on satellites or aircrafts is much needed for resource management, environmental monitoring, disaster response, and homeland defense. Remote sensing data considered include those from multispectral, hyperspectral, radar, optical, and infrared sensors. Classification is often one of the major tasks in information processing. For example, we need to identify vegetations, waterways, and man-made structures from remote sensing of earth. The large amount of data available makes remote sensing data uniquely suitable for statistical pattern recognition. This paper will address several issues on statistical pattern recognition that are related to information processing in remote sensing. Though the paper is largely tutorial in nature, some specific issues considered are image models for characterization of contextual information, neural networks for image classification, and the performance measures. Either to supplement the capability of sensors or to effectively utilize the enormous amount of sensor data, many advances in statistical pattern recognition can be very useful in machine recognition of the data. The potentials and opportunities of using statistical pattern recognition in remote sensing are indeed unlimited. [Copyright &y& Elsevier]

Abstract: The intentional break-up of the Fengyun-1C spacecraft on 11 January 2007 via a hypervelocity collision with a ballistic object created the most severe artificial debris cloud in Earth orbit since the beginning of space exploration. More than 2000 debris of the order of 10cm or greater in size have been identified by the US Space Surveillance Network. The majority of these debris reside in long-lived orbits. The NASA Orbital Debris Program Office has conducted a thorough examination of the nature of the Fengyun-1C debris cloud, using Space Surveillance Network (SSN) data for larger debris and special Haystack radar observations for smaller debris. These data have been compared with the NASA standard satellite break-up model for collisions, and the results are presented in this paper. The orbital longevity of the debris have also been evaluated for both small and large debris. The consequent long-term spatial density effects on the low Earth orbit regime and the potential effect of the debris cloud on the growth of the near-Earth satellite population have been addressed. [Copyright &y& Elsevier]

Abstract: The first airborne laser altimetry measurements of a glacier in South America are presented. Data were collected in November of 2001 over Glaciar Tyndall, Torres del Paine National Park, Chilean Patagonia, onboard a Twin Otter airplane of the Chilean Air Force. A laser scanner with a rotating polygon-mirror system together with an Inertial Navigation System (INS) were fixed to the floor of the aircraft, and used in combination with two dual-frequency GPS receivers. Together, the laser–INS–GPS system had a nominal accuracy of 30 cm after data processing. On November 23rd, a total of 235 km were flown over the ablation area of Glaciar Tyndall, with 5 longitudinal tracks with a mean swath width of 300 m, which results in a point spacing of approximately 2 m both along and across track. A digital elevation model (DEM) generated using the laser altimetry data was compared with a DEM produced from a 1975 map (1:50,000 scale — Instituto Geográfico Militar (IGM), Chile). A mean thinning of −3.1±1.0 m a−1 was calculated for the ablation area of Glaciar Tyndall, with a maximum value of −7.7±1.0 m a−1 at the calving front at 50 m a.s.l. and minimum values of between −1.0 and −2.0±1.0 m a−1 at altitudes close to the equilibrium line altitude (900 m a.s.l.). The thinning rates derived from the airborne survey were similar to the results obtained by means of ground survey carried out at ∼600 m of altitude on Glaciar Tyndall between 1975 and 2002, yielding a mean thinning of −3.2 m a−1 [Raymond, C., Neumann, T.A., Rignot, E., Echelmeyer, K.A., Rivera, A., Casassa, G., 2005. Retreat of Tyndall Glacier, Patagonia, over the last half century. Journal of Glaciology 173 (51), 239–247.]. A good agreement was also found between ice elevation changes measured with laser data and previous results obtained with Shuttle Radar Topography Mission (SRTM) data. We conclude that airborne laser altimetry is an effective means for accurately detecting glacier elevation changes in Patagonia, where an ice thinning acceleration trend has been observed during recent years, presumably in response to warming and possibly also drier conditions. [Copyright &y& Elsevier]

Summary: Application of regular grid-based distributed hydrological models requires information related to river drainage networks, such as flow directions, flow accumulated areas, basin delineation, and length and slope of river reaches for every grid cell. Most of those data may be extracted automatically from Digital Elevation Models (DEM). However, when dealing with large basins, available DEMs are usually in higher spatial resolution than the model grid. Upscaling procedures have therefore been developed to extract low-resolution flow directions and flow accumulated areas from relatively high-resolution DEMs. This paper presents a new methodology, which extends the upscaling method, to automatically extract length and slope of river reaches for large-scale grid-based hydrological models. The proposed method is new and is believed to be the first attempt to produce such information automatically from DEMs. The methodology was applied to parts of the Uruguay river basin in South-America, using the globally-wide available DEM produced by the Shuttle Radar Topography Mission (SRTM-90m). Quality of results was assessed by comparing calculated river lengths with distances measured over vectorized river networks, which were assumed to be correct. It was shown that the proposed methodology adequately assigns river lengths to every model cell, while ensuring that the whole length of the streams is considered. The effect of DEM resolution on calculated river length errors was analyzed by resampling the SRTM DEM to three different cell sizes, with best results obtained for the higher resolution DEM. The modification of the original high-resolution DEM through the process known as stream burning was also tested, largely improving the quality of the results. Finally, optimal distance transforms were used for the calculation of distance increments, instead of Euclidean local distances, giving results that were generally better. The quality of results for calculated slope values could not be assessed because no reliable data were available for comparison. [Copyright &y& Elsevier]

Abstract: Shuttle radar topographic mission (SRTM) has created an unparalleled data set of global elevations that is freely available for modeling and environmental applications. The global availability (almost 80% of the Earth surface) of SRTM data provides baseline information for many types of the worldwide research. The processed SRTM 90 m digital elevation model (DEM) for the entire globe was compiled by Consultative Group for International Agriculture Research Consortium for Spatial Information (CGIAR-CSI) and made available to the public via internet mapping interface. This product presents a great value for scientists dealing with terrain analysis, thanks to its easy download procedure and ready-to-use format. However, overall assessment of the accuracy of this product requires additional regional studies involving ground truth control and accuracy verification methods with higher level of precision, such as the global positioning system (GPS). The study presented in this paper is based on two independent datasets collected with the same GPS system in Catskill Mountains (New York, USA) and Phuket (Thailand). Both datasets were corrected with differential base station data. Statistical analysis included estimation of absolute errors and multiple regression analysis with slope and aspect variables. Data were analyzed for each location separately and in combination. Differences in terrain and geographical location allowed independent interpretation of results. The results of this study showed that absolute average vertical errors from CGIAR dataset can range from 7.58±0.60 m in Phuket to 4.07±0.47 m in Catskills (mean±S.E.M.). This is significantly better than a standard SRTM accuracy value indicated in its specification (i.e. 16 m). The error values have strong correlation with slope and certain aspect values. Taking into account slope and aspect considerably improved the accuracy of the CGIAR DEM product for terrain with slope values greater than 10°; however, for the terrain with slope values less than 10°, this improvement was found to be negligible. [Copyright &y& Elsevier]

Summary: The focus of this paper is to develop a methodology to answer the question: do the spatially distributed soil water estimates produced by operational distributed hydrologic models provide potential benefits for agriculture? The formulation quantifies the potential value through a cost–loss analysis, whereby cost for the farmer is associated with the decision to irrigate the field and loss is associated with the decision not to irrigate while damaging soil water deficits occur. Farmer decisions are made in view of the likelihood of damaging events as estimated by the ensemble distributed model simulations of soil water deficit. The ensemble simulations account for parametric and radar rainfall uncertainty. The application area for the economic value analysis is the farmland of the Illinois River watershed in northwestern Arkansas (mainly) and eastern Oklahoma, for which operational-quality distributed model input is available. The land is used to produce hay for feed. The analysis indicates that there is substantial potential economic value in using the ensemble soil water estimates to make decisions regarding irrigation within the watershed for the months of July, August and September, when severe soil water deficits may occur. The benefits are higher for lower cost–loss ratios and for higher yield plants. They exhibit considerable spatial variability within the watershed in agreement with the spatial variability of the incidence of soil water deficits and with the spatial variability of the ability of the ensemble model simulations to reproduce this variability. The results of this study warrant additional analysis of the economic value of distributed model simulations in other regions, different distributed models and for other types of crops. Consideration of forecasts in addition to simulations is also an important next step. [Copyright &y& Elsevier]

Abstract: The accurate evaluation of current underground infrastructure must be done before any crucial decisions regarding lifecycle analysis, rehabilitation and replacement intervals and appropriate remedial methods can be made. Unfortunately, traditional technologies and management approaches have been limited by the use of insufficient data in the evaluation of the structural integrity of an aged infrastructure. This paper describes an innovative method for assessment of underground pipe, utilizing Ground Penetrating Radar (GPR) and Digital Scanning and Evaluation Technology (DSET) to collect accurate information about the condition of a buried pipeline. Prediction modeling, using logistic regression, to measure the extent of deterioration of the infrastructure system, is described. A case study applying this innovative technology to sections of large diameter PVC lined concrete pipe in the City of Phoenix, Arizona, is presented. [Copyright &y& Elsevier]

The greatest threat to U.S. homeland security comes from illegals who enter the country through its porous borders in order to attack. The tide of illegal immigration must be stemmed in order to secure the United States against terrorism. It is all too easy for illegal immigrants to slip in beneath the radar, eschewing the legalization process and never being detected and deported. And as long as the benefits of illegally immigrating outweigh the costs, the influx will continue. Legal immigration itself needs reform, too; particularly the visa-waiver program and the rules governing dual citizenship, which pose further security challenges. Federal government officials must overcome their fear of alienating ethnic voters and American business, enhance border security, and reform the nation''s immigration policies. [Copyright &y& Elsevier]

Abstract: Creeping along the North Anatolian fault (NAF) at Ismetpasa (Turkey) was discovered some thirty years ago, about a decade after the first observations of the phenomenon along the San Andreas fault in California. However, little is known about its lateral extent and rate. In order to study its three dimensional nature and rupture characteristics, we use Synthetic Aperture Radar Interferometry (InSAR) and elastic dislocation models compared also with field observations. Interferograms with temporal baselines ranging between 1.25 and 5 years show that the creeping section starts at the western termination of the 1943 (M =7.6) earthquake rupture. It continues about 70-km to the west, overlapping with the eastern part of the 1944 (M =7.3) earthquake rupture. Offsets along strike indicate a maximum creep rate of 11±3 mm/year near the mid point of the creeping section decreasing gradually towards the edges. Near Ismetpasa, InSAR data yield 8±3 mm/year of creep rate, consistent with recent instrumental (triangulation and creepmeter) measurements. Modeling of the InSAR and GPS data suggests that the fault-creep occurs most probably at a shallow depth (0–7 km). Our analysis combined with previous studies suggests that creeping might have commenced following the 1944 earthquake, and thus may be a long-lasting, but transient slip episode. [Copyright &y& Elsevier]

Abstract: In this paper, the authors examine models of probability distributions for sampling error in rainfall estimates obtained from discrete satellite sampling in time based on 5 years of 15-min radar rainfall data in the central United States. The sampling errors considered include all combinations of 3, 6, 12, or 24 h sampling of rainfall over 32, 64, 128, 256, or 512 km square domains, and 1, 5, or 30 day rainfall accumulations. Results of this study reveal that the sampling error distribution depends strongly on the rain rate; hence the conditional distribution of sampling error is more informative than its marginal distribution. The distribution of sampling error conditional on rain rate is strongly affected by the sampling interval. At sampling intervals of 3 or 6 h, the logistic distribution appears to fit the conditional sampling error quite well, while the shifted-gamma, shifted-weibull, shifted-lognormal, and normal distributions fit poorly. At sampling intervals of 12 or 24 h, the shifted-gamma, shifted-weibull, or shifted-lognormal distribution fit the conditional sampling error better than the logistics or normal distribution. These results are vital to understanding the accuracy of satellite rainfall products, for performing validation assessment of these products, and for analyzing the effects of rainfall-related errors in hydrological models. [Copyright &y& Elsevier]

This paper reviews the characteristics of wind speeds in tropical cyclones revealed by data from modern automatic weather stations, dropwindsondes, and Doppler radar in the United States. In general winds in tropical cyclones are found to possess the same relationships between surface and gradient speeds as extra-tropical cyclones and the same level of gustiness. Relationships between wind speeds and insurance losses are developed and used to refine the Beaufort Scale.It is shown that statements issued by the National Hurricane Center (NHC), the US government agency responsible for issuing warnings and statements of current and past conditions in tropical cyclones, do not reflect the surface data now available. It is also shown that the design wind speeds in tropical-cyclone-prone areas of the United States, which are based on computer simulations, appear to be unreasonably high in the light of wind speed characteristics presented in this paper and speeds measured in past storms.The findings reported are discussed in the context of information presented in 1963 by Shellard and Davenport in the first major wind engineering conference. [Copyright &y& Elsevier]

The Portland metropolitan area historically is the most seismically active region in Oregon. At least three potentially active faults are located in the immediate vicinity of downtown Portland, with the Portland Hills Fault (PHF) extending directly beneath downtown Portland. The faults are poorly understood, and the surface geologic record does not provide the information required to assess the seismic hazards associated with them. The limited geologic information stems from a surface topography that has not maintained a cumulative geologic record of faulting, in part, due to rapid erosion and deposition from late Pleistocene catastrophic flood events and a possible strike-slip component of the faults. We integrated multiple high-resolution geophysical techniques, including seismic reflection, ground penetrating radar (GPR), and magnetic methods, with regional geological and geophysical surveys to determine that the Portland Hills Fault is presently active with a zone of deformation that extends at least 400 m. The style of deformation is consistent with at least two major earthquakes in the last 12–15 ka, as confirmed by a sidehill excavation trench. High-resolution geophysical methods provide detailed images of the upper 100 m across the active fault zone. The geophysical images are critical to characterizing the structural style within the zone of deformation, and when integrated with a paleoseismic trench, can accurately record the seismic history of a region with little surface geologic exposure. [Copyright &y& Elsevier]

As part of a program to determine the location and geometry of the San Andreas Fault (SAF) buried beneath shallow sediments near its northern landward limit, three >20-m-long parallel trenches were constructed at positions distributed over a distance of ∼55 m. The majority of excavated material comprised unconsolidated fluvial sediments deposited in a number of paleochannels. Single zones of active faulting identified in each of the trenches were initially interpreted in terms of a solitary strand of the SAF. To map the SAF between and beyond the trenches and to detect other active fault zones hidden by the young sedimentary cover, we collected a dense ground-penetrating radar (georadar) data set across a 23.2×72 m area. The data were recorded using a semi-automated acquisition system that included a conventional georadar unit coupled to a self-tracking laser theodolite with automatic target recognition capabilities. Since these data were plagued by system ringing as a result of the moderate-to-high electrical conductivities of the surficial sediments, an extensive data processing scheme was required to extract meaningful subsurface information. The final processed georadar volume (cuboid) contained numerous subhorizontal and trough-shaped reflections that originated from the fluvial paleochannels. Using the geological interpretation of the trench walls as a guide to pick semi-automatically the times of the most important reflecting horizons, we discovered that alignments of the nearly linear boundaries of these horizons defined two NW–SE trending strands of the SAF within the survey area. The georadar expression of the eastern SAF strand could only be traced over a distance of ∼38 m. It had been intersected in the northern trench. In contrast, the western SAF strand extended over the entire length of the georadar volume and had been intersected in the central and southern trenches. Prominent reflections on georadar cross sections were found to be vertically displaced by 0.2–0.3 m across both SAF strands. A conspicuous linear-trending feature observed on horizontal sections at 3.3–3.6 m depth was laterally offset by 4.5–5.5 m along the eastern SAF strand. The interpreted vertical and horizontal offsets could have been generated by the 1906 San Francisco earthquake and/or earlier events. Undetermined amounts of aseismic slip may also have occurred along the newly defined SAF strands. [Copyright &y& Elsevier]

Recent developments in interferometric radar remote sensing provide a method for deriving detailed topographic and slope information for fault-scarp detection. In October 1996, the airborne TOPSAR instrument [IEEE Trans. Geosci. Remote Sens., 30 (1992) 933] was flown over southwest Nevada and east-central California. Topography calculated from TOPSAR data are in the form of a high-resolution (5-m spatial grid) digital elevation model (DEM). In this study, we focus upon the large, steep fault scarps that cut alluvium and alluvial fans in Fish Lake Valley, east of the White Mountains of Nevada–California. A series of topographic profiles extracted from the DEM reveal that the larger fault scarps are greater than 40 m in height and that the average midsection slope angle for all measured scarps is approximately 23°. These large scarps are the product of multiple offsets rather than a single event. Other relevant geomorphic features present in the digital topography include splays and benches along the main fault, levees, cutbanks, gullies incising fault scarp slopes, shutterridges, offset drainage, and small normal faults with scarp heights of only 4–6 m. Field work corroborated general geomorphologic landforms, confirmed fault-scarp morphometry, and aided the evaluation of the accuracy of the DEM. We are also able to assess fault segmentation models that divide the Fish Lake Valley fault zone (FLVFZ) into discrete segments based upon surface-rupture characteristics. [Copyright &y& Elsevier]

The features of the 1997–1998 El Nin˜o event were analyzed by Empirical Orthogonal Functions (EOF) statistical methods applied to the remotely sensed sea surface temperature anomalies (SSTA) measured by AVHRR radiometers; anomalies of water circulation derived from sea surface height anomalies (SSHA) measured by TOPEX/Poseidon radar altimeter; and meteorological information (air temperature, upwelling index, and wind stress curl). EOF statistics demonstrated the features of an El Nin˜o event during the second half of 1997 and the first half of 1998, with sea level elevated along the coast and with SSHA gradients, indicating a retarding of both the equatorward California Current and the alongshore poleward Southern California Countercurrent. The positive SST anomaly developed first in the Southern California Bight and then in the zone of upwelling to the north of Point Conception. The anomalies of upwelling index and the wind stress curl pattern also changed during the El Nin˜o event, but these changes occurred later than hydrographic variations and were too weak to explain the observed changes in SSTA and SSHA. We conclude that off central and southern California oceanic teleconnection (i.e., the consequences of propagation northward of coastally trapped downwelling waves) was responsible for the 1997–1998 El Nin˜o event. [Copyright &y& Elsevier]

The aim of the present study is to see if by conducting research on sudden infant death syndrome (SIDS), one of major contributing factors to infant mortality in Japan, infant mortality can be reduced. Concrete approaches taken in this study took four different directions: elucidation of SIDS etiology, prevention, elucidation of its social aspects (education) and the investigation of administrative aspects. At the same time, an attempt was made to get better grasp on the epidemiological trends in infant mortality, including that of SIDS. The idea behind this etiological approach was to unify hitherto separate approaches taken by those in epidemiological, physiological and pathological fields. A molecular-biological approach was also added. Physiologically hypothesized causes of SIDS—apnea and arousal disorder—together with the epidemiologically presumed risk factor of sleeping position, were examined jointly from a pathological viewpoint. Research in the first 2 years of the grant found that hypoxia reflected by gliosis in the brain stem arousal pathway was related to the duration of sleep apnea. Research in the final year of the grant found the possibility of organic fragility in the brain stem arousal pathway, particularly in periaqueducal gray matter and pedunculopontine nucleus reflected by apoptosis and neuronal plasticity. These findings gave support to the arousal disorder hypothesis in SIDS. Application of the restriction landmark genomic scanning (RLGS) method supported the possibility of locating a site for a SIDS-specific gene. The US collaborative home infant monitoring evaluation (CHIME) currently in use was evaluated. In addition, three new monitoring methods were developed: a non-invasive multi-channel pressure-sensing bed, microwave radar, and a pacifier that functions as a suckometer which can be used to evaluate a neonate’s autonomic nervous functions. Social (educational) activities included: surveys of the current state of educational campaigns on SIDS in other countries, epidemiological evaluation of campaigns run by the Japan SIDS families’ Association to evaluate the effectiveness of the SIDS campaign, and creation of a home page, mostly to inform the public about the output from this research group. “Guidelines for Death Scene Investigation of Sudden, Unexplained Infant Deaths: Recommendations of Interagency Panel on Sudden Infant Death Syndrome” was translated into japanese. Activities that concerned administrative measures included clarification of the unique nature of SIDS-related trials in Japan when compared to those in the United States. Other concrete administrative proposals were: a pressing need to increase the rate of SIDS-related autopsies to facilitate a better etiological understanding and, for this purpose, establishing regulations in local jurisdictions and amending Article 8 of the Postmortem Examination and Corpse Preservation Act, keeping in perspective the medico-economic evaluation of the japanese medical examiner system. For these proposals to be realized, establishment of a new office in charge of administrative and approved autopsies at the national level of government is desirable. Also pointed out were the different opinions held among specialists concerning the diagnosis of SIDS and their need to hold multiple conferences to unify their views. Basic data for these conferences were provided from epidemiological examinations of infant mortality. [Copyright &y& Elsevier]

The timing and intensity of the effects of the 1997–98 El Nin˜o on sea-surface temperature (SST) and coastal sea level along the US west coast are examined using in situ time-series measurements, and the effects on upper ocean currents on the continental shelf and slope off Oregon and northern California are examined using repeated shipborne ADCP transects, a mid-shelf mooring off Newport Oregon and an HF surface current radar. An initial transient positive anomaly was observed in both adjusted sea level and SST during May–June 1997, followed by anomalously high coastal sea levels, generally strongest during September 1997 through February 1998 and abruptly returned to normal in late February 1998, and by positive temperatures anomalies over the mid-shelf that persisted longer, into April 1998. Low-frequency coastal sea-level anomalies propagated poleward at 2.1 m/s. Poleward flow over the shelf and slope was enhanced at most depths during the El Nin˜o, compared with following years. Northward currents in the upper 12 m over the continental shelf off Newport, Oregon averaged 13.7 cm/s stronger during August 1997 through February 1998 than during the same period the following year. Enhanced poleward flow was present at all latitudes sampled during November 1997 and February 1998, particularly over the continental slope. These transects also provided clear views of a fall/winter equatorward undercurrent, which was both strongest and had the most alongshore similarity of form, during the ENSO. Finally, subsurface-intensified anticyclonic eddies originating in the poleward undercurrent appear to be a recurrent feature of the circulation off Newport late in the upwelling season. [Copyright &y& Elsevier]

Subsurface drainage pipes are commonly used in the Midwestern United States to reduce excess soil moisture and improve crop yields. However, they are the considerable source of nonpoint pollution due to nutrient losses. Detecting the locations of drainage pipes is crucial for water quality management, but information about drainage pipe maps is often privately owned and unavailable. In this study, we propose an ensemble learning approach that uses eight fully convolutional networks (FCNs), including well-known architectures such as Unet, DenseNet, and Wnet, to detect subsurface drainage pipe locations from aerial images. Each FCN model is trained and validated using an aerial image dataset, taking a 256 × 256 × 3 pixel aerial image patch as input and outputting a pixel-wise drainage pipe detection map. Weighted averaging is then applied to the individual FCN outputs to create a unified drain pipe detection map. The performance of the proposed approach is evaluated using large-scale aerial image data that has not been used during the training and validation phases. The results demonstrate that the proposed approach provides accurate and more robust drain pipe detection over the case of using an individual FCN model. We further explore the effects of image resolution for the effective use of the proposed drain pipe detection approach. • Our ensemble learning method detects subsurface pipes accurately and robustly. • The ensemble model outperforms image processing and single machine learning models. • An optimal resolution can enhance the performance of the ensemble learning model. [ABSTRACT FROM AUTHOR]

Smoother pavement provides a comfortable, safe and economical riding experience to the public and prolongs the life of the pavement with low maintenance costs. Hence, obtaining a smooth pavement is considered a necessity by many transportation agencies around the world. In order to achieve a smooth pavement, smoothness specifications are developed. Smoothness specifications mainly consist of four parts: smoothness measuring equipment, smoothness indices and analysis method, acceptance limits, and incentive/disincentive payment schemes. This paper summarizes smoothness specifications in the United States and various countries around the world and provide an overview on the comparison of smoothness measurement. The smoothness measuring devices, indices, limits and payment schemes vary from country-to-country International Roughness Index is the most used smoothness index in the US and around the world. Inertial profilers are used to measure the pavement profile for smoothness. [ABSTRACT FROM AUTHOR]

The article comments on the review made by Dr. Kwonil Jung and Dr. Linda Saif on the etiology, epidemiology, pathogenesis , and immunoprophylaxis of porcine epidemic diarrhea virus (PEDV) infection. Topics discussed include the reason that coronaviruses such as PEDV continues to remain on the radar of global health professionals, characteristics of the disease associated with PEDV, and finding on the PEDV strains identified in U.S. pigs in 2013.

Abstract: The NASA IceBridge flights have obtained critical observations for Earth''s polar ice since ICESat stopped collecting data in 2009. This study develops an automatic method in processing IceBridge Airborne Topographic Mapper (ATM) altimeter L1B data (one elevation per 3–4m horizontally) to derive a local sea level height for referencing snow freeboards and then computing sea ice thicknesses. Four 30-km L1B profiles (A, B, C and D) flown on October 21, 2009 over the Bellingshausen Sea in Antarctica are selected. The local sea level reference is first obtained by visual examination of ATM L1B heights over leads or thin ice identified on images simultaneously acquired from the Digital Mapping System camera (called manual selection). This sea level reference is then used as ground truth to validate sea level heights derived by automatic calculations using five thresholds of 2%, 1%, 0.5%, 0.2% and 0.1% of the lowest L1B data. The L1B_0.2% method gives a similar sea level height as from the L1B manual selection, by mean (absolute) difference of −0.01 (0.06) m. The sea level heights demonstrate a near linear gradient of 0.01m/km to 0.03m/km within each ~30-km L1B profile along the flight track from section A to D. The resulting mean snow freeboards are 0.59m, 0.67m, 0.53m, and 0.60m on sections A, B, C and D, respectively. Three empirical equations and the buoyancy equation (with zero ice freeboard assumption) all give similar statistics in ice thickness estimation with mean ice thicknesses of 1.91m for section A, 2.16m for B, 1.76m for C, and 1.94m for D. The sea level over leads cannot be accurately resolved from the ATM L2 data (~60m x 80m horizontal averaging). However, by using a sea level reference obtained from the L1B data, the ATM L2 data can achieve reasonable ice thickness estimates with mean absolute difference of only 0.10m compared to thickness derived from the L1B data. [Copyright &y& Elsevier]

Abstract: We investigated the influence on flow resistance of flow structure and turbulence at the reach scale in a mountain channel using 3-D velocity measurements and geostatistical analysis to understand the complexity of the flow structure in a reach with limited bed irregularities. The increase in flow resistance at low flows in a plane-bed reach was not fully explained by grain resistance, therefore detailed 3-D velocity measurements were made to investigate spatial variability in velocity and turbulence components and potential controls on flow resistance. One plane-bed reach was surveyed over two stages in Fraser Experimental Forest, Colorado, using a combination of a total station, LiDAR (Light Detection and Ranging), and a SonTek Flowtracker handheld ADV (acoustic Doppler velocimeter). LiDAR was used to capture bank and channel geometry at low flows, whereas the water surface and bed data were collected with the total station at all flows. We used the standard deviation of bed elevation (σ b ) within a moving window as an index of roughness height (k s ) and calculated the relative submergence of the bed at different stages as h/k s , where h is the local flow depth. ADV measurements were collected on a grid with a 0.3m to 0.5m spacing. Geostatistical analysis of the velocity data indicated that the flow was highly three-dimensional and varied based on stage, demonstrating that even small irregularities in the bed have a significant influence on the flow characteristics. The streamwise component was the largest at both low and high flow, but varied more throughout the reach at low flow. At high flow, the greatest streamwise velocities were located within the thalweg. Areas of upwelling and downwelling also varied based on stage, with this component being strongly influenced by small changes in the morphology at high flow, and by protuberant grains at low flows. The cross-stream velocity and turbulence components were controlled by the flow structure and less by the roughness of the bed. The turbulence intensity is significant when considering hydraulics for predicting sediment transport and for habitat assessment. The plane-bed flow patterns were compared to results from a pool-riffle reach in the North Fork Cache La Poudre River, a step-pool reach in East St. Louis Creek, and a step-pool reach in Italy on the Rio Cordon. The comparison of the 3-D velocities among channel types showed that the plane-bed reach has higher streamwise velocities, but similar values of cross-stream and transverse velocities. Streamwise turbulence intensities were similar in both the plane-bed and step-pool reach in East St. Louis Creek. The analysis revealed that the connection between the flow characteristics and the channel was not only related to the gross morphology and location of larger clasts, but also to the development of shear layers from the convergence of flow. Therefore, it is essential to understand how water moving in one direction can alter the characteristics of another component of flow and how this interaction is connected to the bed morphology. [Copyright &y& Elsevier]

Abstract: Large areas of forest in the US and Canada are affected by insects and disease each year. Over the past century, outbreaks of the Eastern spruce budworm have become more frequent and severe. The notion of designing a more pest resistant landscape through prescriptive management practices hinges on our ability to effectively model forest–insect dynamics at regional scales. Increasingly, more detailed pixel-wise estimates of forest biophysical parameters are needed for such endeavors. Lidar technology, although promising, is not yet viable for repeated regional accounting, necessitating the development of methods which take advantage of existing spaceborne assets. Our objective is to use one of these assets (SPOT-5) to estimate a large set of forest structural attributes at a finer spatial grain size (5 m and 10 m) over a broader area than is currently available for the purpose of supplying needed input data for disturbance simulation modeling. We employ neighborhood statistics (standard deviation, variance, sill variance, and ratios of these metrics at 5 and 10 m) calculated from SPOT-5 sensor data and derivatives to estimate and map tree canopy diameter (CDIA), bole diameter at breast height (DBH), tree height (HT), crown closure (CC), vertical length of live crown (LC), and basal area (BA). A partial least squares (PLS) regression approach was used with these local statistics and field data to produce models for pixel-wise estimation and mapping of mean values, respectively, for hardwood and coniferous forest CDIA (R 2 =0.82 and 0.93, RMSE 0.62 and 0.47 m), DBH (R 2 =0.82 and 0.90, RMSE 2.92 and 3.75 cm), HT (R 2 =0.69 and 0.92, RMSE 1.27 and 1.59 m), CC (R 2 =0.52 and 0.68, RMSE 5.49 and 6.02%), LC (R 2 =0.58 and 0.81, RMSE 0.96 and 1.25 m), and BA (R 2 =0.71 and 0.74, RMSE 2.47 and 4.58 m2 ha−1) for a 3600 km2 area in northeast Minnesota. This approach for quantifying forest structure is robust in the sense that a detailed forest cover type map is not required to stratify analysis at any step in the process. Hence, we show that multi-resolution SPOT-5 data are a practical alternative to lidar for regional characterization of forest biophysical parameters. However, lidar data may potentially be used to calibrate these SPOT-based structure models in the future. [Copyright &y& Elsevier]

Abstract: ESA’s Space Debris Office provides an operational service for the assessment of collision risks of ESA satellites. Currently, the ENVISAT and ERS-2 missions in low Earth orbits are covered by this service. If an upcoming high-risk conjunction event is predicted based on analysis of Two-Line Element (TLE) data from the US Space Surveillance Network, then independent tracking data of the potential high-risk conjunction object are acquired to improve the knowledge of its orbit. This improved knowledge and the associated small error covariances derived from the orbit determination process scale down the position error ellipsoid at the conjunction epoch. Hence, for the same miss-distance, in most cases an avoidance manoeuvre can be suppressed with an acceptable residual risk. During the past years sophisticated stand-alone tools have been developed and maintained at ESA’s Space Debris Office. The central tools for analysing conjunction events are the collision risk assessment software CRASS and the orbit determination software ODIN. ODIN is used to process tracking data and to determine orbits by least-squares fits of tracking data, or of pseudo-data in terms of osculating orbit states, which can for instance be derived from TLEs. On this basis, estimates of TLE error covariances also can be established as input for initial collision risk assessments. For ESA’s automated routine conjunction event assessments which are embedded in a daily process with 7-day predictions, the handling of high-risk events is work-intensive. This shortcoming has been addressed by the implementation of a job scheduler, and automated procedures to facilitate the processing of tracking data, the update of ephemerides and covariances, and the update of conjunction geometries and collision risk estimates. The application of the upgraded software environment is illustrated through two exemplary, recent conjunction events of ENVISAT (02009A) with Russian Cosmos satellites: the conjunction event on 2008-Jan-09 19:00 (UTC) with the chaser object COSMOS-1624 (85006A), and the conjunction event on 2007-Nov-14 13:49 (UTC) with the chaser object COSMOS-1486 (83079A). [Copyright &y& Elsevier]

The Energy Act of 2020 authorizes $1 billion over five years from 2021 to 2025 to support energy storage development in the United States. In addition, the Federal Energy Regulatory Commission (FERC) Orders 841 and 2222 opened the wholesale energy markets for distributed energy resources, including energy storage. The statute and orders pave the way for novel energy storage technologies to participate in electricity markets as the qualifying facilities, thereby expanding opportunities for energy storage development. However, the existing policy, legal, and regulatory regime, including these much-welcomed newcomers, fails to recognize and support the entire spectrum of benefits that some forms of energy storage create. In this paper, we focus on Pumped Underground Storage Hydro (PUSH), a variant of pumped hydro storage (PHS), which currently provides over 90% of the world's energy storage capacity. PUSH operates with the same principle as PHS; however, it is an entirely underground variant of PHS. In addition to becoming competitive in the wholesale electricity market, PUSH facilities can be developed as community infrastructure in the postindustrial landscape, particularly in abandoned underground mines. Given federal energy law and policy development, this paper identifies how communities with abandoned mines, technically feasible for PUSH facilities and operating as municipal-owned utilities or cooperatives, can participate and take advantage of federal legislation. We further look into the implications through the lens of technical, economic, and social aspects of energy justice. We consider energy justice as a conceptual framework that seeks to explain the occurrence of injustice within energy system decisions and outcomes and how policymakers can respond to these injustices. We use it as a conceptual tool for understanding policy formulation and detailing the energy system's missing ethical and justice dimension. We argue that as a technically mature technology, PUSH facilities can act as a potential means to speed up the energy transition in the United States. The federal and state law along with utility market structures are vital in shaping the potential opportunities and barriers for energy storage facilities like PUSH. We show that although it supports PUSH development, there are gaps in the current market structure, specifically in the regulatory framework, when seen through the lens of justice and valuation of just energy services. These gaps limit the realization of utility-scale energy storage technology's potential to fully contribute to a decarbonized energy system that is more resilient and more just than the incumbent system. [ABSTRACT FROM AUTHOR]

Abstract: Introduction: Adverse weather conditions have a major impact on National Airspace System (NAS) operations. They create safety hazards for pilots, constrain the usable airspace for air traffic control (ATC), and reduce the overall capacity of the NAS. A system-wide dissemination of weather information to controllers could theoretically improve safety and efficiency. Problem: However, it is currently unclear what weather information would be beneficial for tactical operations. Furthermore, no previous research has empirically evaluated optimal presentation designs for ATC weather displays. Ill-designed weather displays can cause safety hazards by presenting redundant information (i.e., by increasing the cognitive load) and display clutter (e.g., by interfering with the visual extraction of traffic data). Method: In the present paper, we outline our use of cognitive work analysis (CWA) techniques for the assessment of weather information needs for terminal controllers. Results: Specifically, we describe how the CWA modeling tools helped us reveal instances in the terminal domain where weather information is lacking or insufficiently disseminated. We used our CWA results to drive the development of weather display concepts and to set up a high-fidelity simulation capability. Impact on Industry: By means of high-fidelity simulations, we can empirically evaluate controller weather information needs in order to propose weather displays for increased aircraft safety and efficiency of terminal operations. [Copyright &y& Elsevier]

Okmok Volcano, in the eastern Aleutian Islands, erupted in February and March of 1997 producing a 6-km-long lava flow and low-level ash plumes. This caldera is one of the most active in the Aleutian Arc, and is now the focus of international multidisciplinary studies. A synthesis of remotely sensed data (AirSAR, derived DEMs, Landsat MSS and ETM+ data, AVHRR, ERS, JERS, Radarsat) has given a sequence of events for the virtually unobserved 1997 eruption. Elevation data from the AirSAR sensor acquired in October 2000 over Okmok were used to create a 5-m resolution DEM mosaic of Okmok Volcano. AVHRR nighttime imagery has been analyzed between February 13 and April 11, 1997. Landsat imagery and SAR data recorded prior to and after the eruption allowed us to accurately determine the extent of the new flow. The flow was first observed on February 13 without precursory thermal anomalies. At this time, the flow was a large single lobe flowing north. According to AVHRR Band 3 and 4 radiance data and ground observations, the first lobe continued growing until mid to late March, while a second, smaller lobe began to form sometime between March 11 and 12. This is based on a jump in the thermal and volumetric flux determined from the imagery, and the physical size of the thermal anomalies. Total radiance values waned after March 26, indicating lava effusion had ended and a cooling crust was growing. The total area (8.9 km2), thickness (up to 50 m) and volume (1.54×108 m3) of the new lava flow were determined by combining observations from SAR, Landsat ETM+, and AirSAR DEM data. While the first lobe of the flow ponded in a pre-eruption depression, our data suggest the second lobe was volume-limited. Remote sensing has become an integral part of the Alaska Volcano Observatory’s monitoring and hazard mitigation efforts. Studies like this allow access to remote volcanoes, and provide methods to monitor potentially dangerous ones. [Copyright &y& Elsevier]

Floods have gained increasing global significance in the recent past due to their devastating nature and potential for causing significant economic and human losses. Until now, flood characterization studies in the United States have been limited due to the lack of a comprehensive database matching flood characteristics such as peak discharges and flood duration with geospatial and geomorphologic information. The availability of a representative and long archive of flooding events spanning 78 years over a variety of hydroclimatic regions results in a spatially and temporally comprehensive flood characterization over the continental U.S. This study, for the first time, employs a large-event database that is based on actual National Weather Service (NWS) definitions of floods instead of the frequently-adopted case study or frequentist approach, allowing us to base our findings on real definitions of floods. It examines flooding characteristics to identify how space and time scales of floods vary with climatic regimes and geomorphology. Flood events were characterized by linking flood response variables in gauged basins to spatially distributed variables describing climatology, geomorphology, and topography. The primary findings of this study are that the magnitude of flooding is highest is regions such as West Coast and southeastern U.S. which experience the most extraordinary precipitation. The seasonality of flooding varies greatly from maxima during the cool season on the West Coast, warm season in the desert Southwest, and early spring in the Southeast. The fastest responding events tend to be in steep basins of the arid Southwest caused by intense monsoon thunderstorms and steep terrain. The envelope curves of unit peak discharge are consistent with those reported for Europe and worldwide. But significant seasonal variability was observed in floods of the U.S. compared to Europe that is attributed to the diversity of causative rainfall ranging from synoptic scales with orographic enhancements in the West Coast, monsoon thunderstorms in the desert Southwest, to land-falling tropical storms and localized, intense thunderstorms in the Southeast. [ABSTRACT FROM AUTHOR]

Summary Flash flooding is one of the most costly and deadly natural hazards in the United States and across the globe. This study advances the use of high-resolution quantitative precipitation forecasts (QPFs) for flash flood forecasting. The QPFs are derived from a stormscale ensemble prediction system, and used within a distributed hydrological model framework to yield basin-specific, probabilistic flash flood forecasts (PFFFs). Before creating the PFFFs, it is important to characterize QPF uncertainty, particularly in terms of location which is the most problematic for hydrological use of QPFs. The SAL methodology (Wernli et al., 2008), which stands for structure, amplitude, and location, is used for this error quantification, with a focus on location. Finally, the PFFF methodology is proposed that produces probabilistic hydrological forecasts. The main advantages of this method are: (1) identifying specific basin scales that are forecast to be impacted by flash flooding; (2) yielding probabilistic information about the forecast hydrologic response that accounts for the locational uncertainties of the QPFs; (3) improving lead time by using stormscale NWP ensemble forecasts; and (4) not requiring multiple simulations, which are computationally demanding. [ABSTRACT FROM AUTHOR]

Summary Several different factors external to the natural hazard of flash flooding can contribute to the type and magnitude of their resulting damages. Human exposure, vulnerability, fatality and injury rates can be minimized by identifying and then mitigating the causative factors for human impacts. A database of flash flooding was used for statistical analysis of human impacts across the U.S. 21,549 flash flood events were analyzed during a 6-year period from October 2006 to 2012. Based on the information available in the database, physical parameters were introduced and then correlated to the reported human impacts. Probability density functions of the frequency of flash flood events and the PDF of occurrences weighted by the number of injuries and fatalities were used to describe the influence of each parameter. The factors that emerged as the most influential on human impacts are short flood durations, small catchment sizes in rural areas, vehicles, and nocturnal events with low visibility. Analyzing and correlating a diverse range of parameters to human impacts give us important insights into what contributes to fatalities and injuries and further raises questions on how to manage them. [ABSTRACT FROM AUTHOR]

Highlights: [•] We reveal the latest Version-7 TMPA algorithm performance over the climate-transitional zone in the southern Great Plains. [•] The satellite rainfall retrieval uncertainties depend on seasons and climate regimes. [•] 3B42V7 demonstrates notable improvement over 3B42V6, especially for the dry region. [•] 3B42RTV7 corrects the widespread rainfall overestimation from 3B42RTV6. [•] V7 TMPA still shows limitations during extreme rainfall events. [ABSTRACT FROM AUTHOR]