Miracle-dz/UniFAR-FTUs huggingface dataset:
Evidence for stratigraphic distortion in the Greenland Ice Core Project (GRIP) ice core during Event 5e1 (120 kyr BP) from gas isotopes

[1] The disturbed stratigraphy of the ice in the lowest 10% of the Greenland GRIP ice core has been previously demonstrated using gas measurements (δ18O of O2 and CH4) on a few meters depth scale. However, rapid ice isotopic variations (on the scale of 20 cm) are experienced in the bottom of the GRIP ice core with complex chemical signatures that make them difficult to reconcile with a disturbed stratigraphy of the ice. This is the case for event 5e1, first described as a dramatic cooling 120 kyr BP. We analyzed at a 5 cm resolution the isotopic composition of the air from 2 m of the GRIP bottom ice core covering event 5e1. The δ15N measurements, combined with a basic firn modeling, lead to the solid conclusion that the rapid event 5e1 is not a climatic event. Rapid variations of δ18O of O2 (δ18Oatm) are in agreement with a disturbed ice stratigraphy. However, the double peak shape of the δ18Oatm, recalling chemical data at the same depth, requires processes of diffusion after the mixing or even postcoring, placing limits to the interpretation of some classical paleoclimatic proxies in small scale mixed ice (<1 m).
Improving fairness in per-packet reservation MAC protocols

Recent and future communications networks have to provide QoS guarantees for a rapidly growing number of various telecommunication services, which can be ensured by application of an efficient MAC layer. Particularly, per-packet reservation MAC protocols are efficient ensuring a good network utilization and realization of QoS for various telecommunications services. However, per-packet reservation protocols suffers from an unfairness because network stations achieve different relative data throughput depending on the traffic characteristics of used services. A fair scheduling between network stations can be ensured if offered data rate per station is known, which is unfortunately not the case. In this investigation it is shown that the offered data rate can be successfully estimated by calculation of so-called effective requesting period per network station, which can be used for implementation of a fair scheduling mechanism. The results show a significant improvement of the fairness behavior in the network if the fair scheduling is applied.
Wildlife Impacts to Big Sagebrush on Reclaimed Mined Lands

Wildlife browsing of Artemisia tridentata ssp. wyomingensis (big sagebrush) on reclaimed coal mined land threatens long-term, sustainable reclamation success. A wildlife-proof exclosure was constructed in 2001 on a 10-year old A. tridentata ssp. wyomingensis reestablishment research site at North Antelope Coal mine in northeastern Wyoming to assess wildlife browsing impacts. Artemisia tridentata ssp. wyomingensis survival, growth, and plant community attributes (species richness, canopy cover, and diversity) were evaluated inside and outside the exclosure, across the original grass seeding rate treatments (0, 16, 32 kg PLS ha−1). Long-term A. tridentata ssp. wyomingensis density decreased across all seeding rates from 1994 to 2002. Higher A. tridentata density, leader (shoot) growth, and canopy cover, along with lower mortality, occurred inside the exclosure across all seeding rates. Lower winter use, higher survival, and lower mortality of A. tridentata ssp. wyomingensis in the 32 compared to the 0 and 16 kg PLS ha−1 seeding rates suggest a beneficial relationship between A. tridentata ssp. wyomingensis survival and higher grass seeding rate. Approximately 33% mortality of marked A. tridentata ssp. wyomingensis plants occurred outside the exclosure. Lepus townsendii campanius (white-tailed jackrabbit), L. californicus melanotis (black-tailed jackrabbit), and Sylvilagus audubonii baileyi (cottontail rabbit) were identified as primary browsers of A. tridentata. Plant species richness, cover, and diversity decreased from 2001 to 2002, probably due to below average precipitation during the study. Defoliation of A. tridentata ssp. wyomingensis was severe, indicating the magnitude of impact from browsing wildlife. Post mining wildlife management and habitat manipulation on adjacent rangeland is suggested to ensure successful reclamation of coal mined lands.
Life in the ice lane: a review of the ecology of salmonids in winter

The main objective of this presentation is describe the results of a review article that we have been writing. In this review, we have summarized the latest information about the survival, habitat use, movement and biotic interactions of salmonids as it relates to the prevailing physical conditions in rivers and streams during the winter. Such information should be of use to both ecologists and resource managers who have interests in identifying where bottlenecks in fish production lie and in effective management of boreal streams. We mostly focus on behavioral and ecological aspects of overwintering fish, but because of the close linkage between physical habitat and fish ecology, both physical and biological elements are discussed.
Integration of satellite sensor data, fuel type maps and meteorological observations for evaluation of forest fire risk at the pan-European scale

This letter presents an integrated model for the assessment of forest fire risk at the European scale that combines three data sources: meteorological data, remotely sensed data, and fuel type maps. Preliminary results on the validation of the fire risk model for the Mediterranean region are presented. Fire event data for 1995 and 1996 served as the basis for testing the model. The obtained results show that the model, which is referred to as Fire Potential Index (FPI), identifies well those areas at risk of fire. In agreement with an increasing fire risk, the slope of the FPI curve increases during the last few days prior to a fire event.
Submarine Tailings Disposal (STD)—A Review

The mining industry is a fundamental industry involved in the development of modern society, but is also the world’s largest waste producer. This role will be enhanced in the future, because ore grades are generally decreasing, thus leading to increases in the waste/metal production ratio. Mine wastes deposited on-land in so-called tailings dams, impoundments or waste-dumps have several associated environmental issues that need to be addressed (e.g., acid mine drainage formation due to sulphide oxidation, geotechnical stability, among others), and social concerns due to land use during mining. The mining industry recognizes these concerns and is searching for waste management alternatives for the future. One option used in the past was the marine shore or shallow submarine deposition of this waste material in some parts of the world. After the occurrence of some severe environmental pollution, today the deposition in the deep sea (under constant reducing conditions) is seen as a new, more secure option, due to the general thought that sulphide minerals are geochemically stable under the reduced conditions prevailing in the deep marine environment. This review highlights the mineralogical and geochemical issues (e.g., solubility of sulphides in seawater; reductive dissolution of oxide minerals under reducing conditions), which have to be considered when evaluating whether submarine tailings disposal is a suitable alternative for mine waste.
Seismic bearing capacity of rough footings on slopes using limit equilibrium

For foundations placed on horizontal ground surfaces, incorporating the effects of earthquake body forces, investigations have been performed by using the method of slices (Sarma & Iossifelis, 1990), limit equilibrium (Budhu & Al-Karni, 1993), the upper bound limit analysis (Richards et al., 1993; Dormieux & Pecker, 1995; Soubra, 1997, 1999) and the method of characteristics (Kumar & Mohan Rao, 2002a). For sloping ground surfaces, on the basis of limit analysis Zhu (2000) has reported an earthquake reduction factor for the bearing capacity factor,$ N_{y}$. By using the method of characteristics, Kumar & Mohan Rao (2002b) have established the variation of the bearing capacity factors with changes in horizontal earthquake acceleration coefficient, h, for different ground inclinations. Two different failure mechanisms (single side and both sides) were used in the analysis. It was indicated that, in the presence of \alpha h, only the single-side failure mechanism remains statically admissible for the computation of Nc and Nq. By contrast, in finding$ N_{y}$, for smaller values of \alpha h and _ both mechanisms were shown to remain statically admissible. As compared with the single-side mechanism, the bearing capacity factor $N_{y}$ was shown to become much smaller on the basis of the both-sides mechanism, especially for very small values of \alpha h and _. It was also indicated that the single-side mechanism remains kinematically admissible in all those cases where no slip has been allowed along the footing–soil interface (rough foundations). Although the approach was quite rigorous, however, it was assumed that the ratio of shear to normal stresses along the foundation–soil interface remains constant. Since the limit equilibrium technique does not require this assumption, it was intended to use this method to determine the seismic bearing capacity of rough foundations on sloping ground. It was simultaneously ensured that the solution remains kinematically admissible in all the cases. The results were thoroughly compared with those reported previously.
Effects of climate change on coastal groundwater systems: A modeling study in the Netherlands

[1] Climate change in combination with increased anthropogenic activities will affect coastal groundwater systems throughout the world. In this paper, we focus on a coastal groundwater system that is already threatened by a relatively high seawater level: the low-lying Dutch Delta. Nearly one third of the Netherlands lies below mean sea level, and the land surface is still subsiding up to 1 m per century. This densely populated delta region, where fresh groundwater resources are used intensively for domestic, agricultural, and industrial purposes, can serve as a laboratory case for other low-lying delta areas throughout the world. Our findings on hydrogeological effects can be scaled up since the problems the Dutch face now will very likely be the problems encountered in other delta areas in the future. We calculated the possible impacts of future sea level rise, land subsidence, changes in recharge, autonomous salinization, and the effects of two mitigation countermeasures with a three-dimensional numerical model for variable density groundwater flow and coupled solute transport. We considered the effects on hydraulic heads, seepage fluxes, salt loads to surface waters, and changes in fresh groundwater resources as a function of time and for seven scenarios. Our numerical modeling results show that the impact of sea level rise is limited to areas within 10 km of the coastline and main rivers because the increased head in the groundwater system at the coast can easily be produced though the highly permeable Holocene confining layer. Along the southwest coast of the Netherlands, salt loads will double in some parts of the deep and large polders by the year 2100 A.D. due to sea level rise. More inland, ongoing land subsidence will cause hydraulic heads and phreatic water levels to drop, which may result in damage to dikes, infrastructure, and urban areas. In the deep polders more inland, autonomous upconing of deeper and more saline groundwater will be responsible for increasing salt loads. The future increase of salt loads will cause salinization of surface waters and shallow groundwater and put the total volumes of fresh groundwater volumes for drinking water supply, agricultural purposes, industry, and ecosystems under pressure.
Analyzing the Impact of Trade in Services on the U.S. Labor Market: The Response of Service Sector Employment to Exchange Rate Changes

Excerpt] The size of the service sector and growing trade in services present the possibility that international trade in services could affect labor market outcomes in the U.S. Yet, very little is known about the impact of trade in services on employment or wages. The objective of this report is to start to address this shortage of empirical evidence and investigate one possible channel – exchange rates – through which international trade in services might influence labor market outcomes.
Distinguishing tropospheric aerosols from thin cirrus clouds for improved aerosol retrievals using the ratio of 1.38‐μm and 1.24‐μm channels

The scattering of solar radiation by cirrus clouds often contaminates aerosol products retrieved from satellite‐based measurements using channels located in the visible and near‐IR spectral region. Previously, it was demonstrated that a narrow satellite channel located near 1.38 μm is very effective in detecting the high level thin cirrus clouds. In this paper, we describe a ratio technique using the 1.38‐μm channel and the 1.24‐μm channel for identifying pixels contaminated by thin cirrus clouds so that improved aerosol and dust products can be obtained. The multi‐channel data acquired with the NASA Moderate Resolution Imaging SpectroRadiometer (MODIS) on the Terra Spacecraft are used to demonstrate this technique.
G.P.S. Heighting in Australia: an introduction

Abstract Problems which can be encountered when using the Global Positioning System to determine differences in height are outlined, with emphasis on relevant characteristics of the Australian surveying environment. Approaches which can be used, if needed, to cope with the difficulties of GPS heighting are mentioned, along with moves to further examine the situation in Australia. Warnings given on this subject in other publications are repeated in this paper which focuses on the problem to provide an introduction to subsequent, more detailed papers.
Forest aboveground biomass estimation using polarization coherence tomography and PolSAR segmentation

Forest aboveground biomass (AGB) is essential for monitoring the carbon cycle budget and climate change. This study proposes a method for the estimation of forest AGB based on polarization coherence tomography (PCT) and polarimetric synthetic aperture radar (PolSAR) segmentation. The data used are the single-baseline polarimetric SAR interferometry data acquired by the German Aerospace Center’s E-SAR sensor at the L-band over the city of Traunstein and its vicinity in 2003. First, vertical structure tomographic profiles (relative reflectivity distribution in vertical direction) were produced by PCT for each pixel and then averaged within each field-surveyed forest stand to obtain the mean tomographic profile. Next, the mean vertical tomographic profiles were parameterized by 10 shape parameters. Several models for biomass estimation were designed based on the relationships between the definition parameters and the in situ measurements using backward step-wise regression and the M-fold (10-fold) cross-validation method. The best model was chosen by evaluation criteria such as R, root mean square error (RMSE), R2, etc. Forest polygons (objects) were produced by image segmentation using forest heights, (produced by coherence optimization representing double-bounce scattering mechanism), (produced by coherence optimization representing the volume scattering mechanism), and the volume scattering mechanism class (produced by Freeman–Durden decomposition and Whishart classification). Finally, the selected model was used to estimate the AGB of each forest polygon and was validated using ground-measured biomass with R2 of 0.883 and RMSE of 39.98 tons ha−1. The results show that the proposed method works well for the estimation of forest AGB. No saturation phenomena have been observed even for the forest stands with AGB larger than 500 tons ha−1.
The interaction between the undertow and the boundary layer flow on a beach

The theoretical result for undertow in a surf zone found by Svendsen [1984a] is combined with a boundary layer solution at the bottom, and it is shown that in this boundary layer the eddy viscosity is small relative to that produced by the breaking. The proper eddy viscosity νt between the surface and the bottom boundary layer is determined by comparison with measurements, which leads to quite accurate reproduction of the velocity profiles. The model also predicts the mean flow in the boundary layer and the mean bottom shear stress, and the results are analyzed for sensitivity to inaccuracies in the basic assumptions.
Solute Transport in Soils Under Conditions of Variable Flow Velocities

Temporal and spatial variabilities of flow distribution significantly influence solute transport in soils. This laboratory study was designed to investigate the effects of temporal variation in flow velocity on pesticide transport in soils. Two pesticides, metribuzin (weakly adsorbed) and atrazine (moderately adsorbed), were chosen along with the following two soils: Cecil (<2 mm) and Sharkey (2–4 mm). Several tritium pulses were introduced into packed soil columns (15 or 30 cm in length) under different flow velocities to obtain velocity-dependent dispersion coefficients (D). Subsequently, several atrazine and metribuzin pulses were introduced under conditions of constant and variable velocities. For each experiment, changes in flow velocity were stepwise using a piston flow pump and were carried out during pulse application and leaching. For constant and variable flow velocity experiments, approximately similar pulse volumes and average flow velocities were maintained. Values of D versus pore water velocity (ν) from tritium breakthrough curves (BTCs) were well described using a linear equation for both soils. Identical BTCs for metribuzin were observed under conditions of constant or variable flow velocities in the Cecil soil column. However, metribuzin transport in the Sharkey soil was significantly influenced by velocity variations. Atrazine transport in the Sharkey soil was also significantly affected by variations in flow velocity. We further examined the error when an average rather than actual velocity distribution was used in BTC representation. The resulting experimental BTCs (concentration versus velocity-averaged pore volume) exhibited early arrival and the appearance of multiple peaks. Moreover, predictions of such BTCs based on the convective-dispersive equation were not successful. We concluded that actual water velocity distributions should be used in BTC representation, and, whenever possible, the use of an average velocity should be avoided.
Early Ludlow monograptids with Devonian morphological affinities

Nilssoni–scanicus Zone deposits (Silurian, early Ludlow) from the Leintwardine and Long Mountain districts of Britain, and the Calarasi Borehole, Moesian Platform of Romania, have yielded a species of monograptid which, whilst resembling rare Ludlow Monoclimacis species, has strong morphological affinities with Devonian monograptids such as Monograptus ramstalensis Jaeger. Because of the occurrence of such structures at a surprisingly low horizon the writers urge caution in identifying age from monotypic assemblages. The difficulties surrounding the affinities of the low Ludlow species necessitates a provisional open nomenclature as Monograptus sp. The possible evolutionary significance is discussed.
The relationship between the decline of Southeastern Australian rainfall and the strengthening of the subtropical ridge

During the 20th century and early 21st century, the subtropical ridge (STR) in the vicinity of eastern Australia has intensified significantly. While the position of the STR has often been the focus of past studies, its influence on rainfall across southern Australia is less pronounced than the influence of the intensity of the ridge. Most of the Australian continent has experienced above average rainfall from 1997 to 2009, but areas of below average rainfall, including southeastern Australia (SEA), exist and tend to match the pattern of the influence of the STR on Australian rainfall. The spatial extent makes the 1997–2009 rainfall deficit in SEA different from previous dry decades such as 1935–1945. It is also noted that the annual cycle of the rainfall deficiency centred on a continuum from March to October overlaps well with the time of the year when the STR intensity has a strong influence on rainfall. Using simple linear statistics, a rainfall decline for the period 1997–2009 equivalent to nearly two thirds of that observed can be inferred from the intensification of the ridge. The apparent southward shift of the ridge in certain seasons does not appear to have had an additional effect on SEA rainfall. During the 1935–1945 drought, almost a third of the rainfall decline can be attributed to the strengthening of the ridge. Finally, it was observed that the intensification of the STR was not monotonic during the 20th century but happened mostly during two extended periods: from 1900 to the 1940s, culminating at the time of the 1935–1945 dry decade, and from 1970 to 2010 culminating with the 1997–2009 rainfall deficit in SEA. That multidecadal behaviour is reminiscent of the global warming of the planet. Copyright © 2012 Royal Meteorological Society
Silurian fades beneath East Anglia

Abstract Core material from proven or probable Silurian sedimentary rocks beneath East Anglia has been re-examined. Four recognizable facies probably represent an environmental transition from anoxic basin slope or outer shelf through oxygenated outer shelf to storm-dominated inner shelf. This transition could have occurred laterally, from east to west across the Anglian Basin, or in time, from Llandovery (early Silurian) up to Př (late Silurian). Partial biostratigraphical constraints allow either interpretation, but the regional setting favours a marked facies transition through time as the Anglian Basin shallowed prior to the Acadian Orogeny. Reddening of the Silurian is mostly secondary beneath the sub-Triassic unconformity.
Assessment of GPS global ionosphere maps (GIM) by comparison between CODE GIM and TOPEX/Jason TEC data: Ionospheric perspective

[1] We performed a comprehensive comparison between GPS global ionosphere map (GIM) and TOPEX/Jason (T-J) total electron content (TEC) data for the periods of 1998–2009 in order to assess the performance of GIM over the global ocean where the GPS ground stations are very sparse. Using the GIM model constructed by the Center for Orbit Determination in Europe at the University of Bern, the GIM TEC values were obtained along the T-J satellite orbit at specific locations and times of measurements and then binned into various geophysical conditions for direct comparison with the T-J TEC. On the whole, the GIM model was able to reproduce the spatial and temporal variations of the global ionosphere as well as the seasonal variations. However, the GIM model was not accurate enough to represent the well-known ionospheric structures such as the equatorial anomaly, the Weddell Sea Anomaly, and the longitudinal wave structure. Furthermore, a fundamental limitation of the model seems to be evident in the unexpected negative differences (i.e., GPS T-J) at night represent the plasmaspheric contribution to GPS TEC, which is maximized, reaching up to 100% of the corresponding T-J TEC values in the early morning sector. In particular, the relative differences decreased with increasing solar activity, and this may indicate that the plasmaspheric contribution to the maintenance of the nighttime ionosphere does not increase with solar activity, which is different from what we normally anticipate.