Miracle-dz/UniFAR-FTUs huggingface dataset:
Hydrometeorological triggers of periglacial debris flows in the Zermatt valley (Switzerland) since 1864

[1] The triggering of debris flows depends on a critical combination of available unconsolidated material and water supply. In periglacial environments, debris flows are generally triggered by liquefaction of loose material in a channel, or by progressive erosion during a large release of water. Here, we link an unusually dense and highly resolved database on periglacial debris flows with meteorological records dating back to AD 1864 to reconstruct ∼150 yr of rainstorms that triggered debris flows at high-elevation sites (source area elevations ranging from 2000 to 4545 m a.s.l.) in the Swiss Alps. Analysis is based on a tree ring-derived frequency series of debris flows from eight torrents, as well as on daily records from three meteorological stations and runoff data from four river gauging stations. Results show that the debris-flow season at these high-altitude sites now is much longer (May to October) than it used to be in the late nineteenth century when activity was limited to June–September. Debris flows early in the season are generally triggered by lower rainstorm totals (<20 mm/day) than those occurring later in the season because early season snowmelt adds considerable amounts of water to the system and therefore facilitates debris-flow formation. Debris flows in May, June, July, and August are triggered primarily by short-duration high-intensity rainstorms (local thunderstorms) whereas late season (September, October) debris flows are commonly related to longer-lasting advective rainstorms.
Fluid flow in discrete joint sets: Field observations and numerical simulations

The distribution of flow within conductive joint sets is influenced by the geometric arrangement of joints and the hydraulic properties of both joints and matrix. We use finite element simulations with an equivalent porous media joint representation to understand the distribution of flow through joints and porous matrix. Isolated joints in a porous media create characteristic flow perturbations in the matrix with reduced fluid potentials near the upstream joint tip, elevated potentials near the downstream tip, and flow shadows adjacent to the joint. In more complex joint systems, flow in any given joint is influenced by its proximity to other joints, resulting in characteristic enhancement or reduction of flow velocities. The permeability ratio (equivalent joint permeability divided by matrix permeability) plays a major role in determining the distribution of flow within complex joint systems. When the permeability ratio is <3.0 orders of magnitude, all joints are indirectly connected to the flow system through the matrix. As joint conductivity increases, flow becomes increasingly localized into directly connected joints. When the permeability ratio exceeds 6.5 orders of magnitude, significant flow occurs only in the directly connected joints. We compare these numerical results with field observations from an ancient reactive flow system nowmore » exposed at the Earth's surface. In the field, 32% of joints are associated with chemically altered halos. By explicitly representing mapped joint distributions in numerical simulations, we estimate that 32% of the joints would conduct significant volumes of fluid if joint permeability is 5 orders of magnitude greater than the matrix permeability. This corresponds to an insitu joint aperture of 2.3 mm, closely resembling the 1.8-mm average joint aperture measured on the present-day outcrop. (c) 1999 American Geophysical Union. « less
Liquid CO2 venting on the seafloor: Yonaguni Knoll IV hydrothermal system, Okinawa Trough

We determined the chemical and isotopic compositions of the liquid CO2 found on Yonaguni IV knoll hydrothermal site, as well as those in hydrothermal fluid venting from the surrounding chimneys. The δ13C of both CO2 and CH4 in the liquid CO2 almost coincide with those in the hydrothermal fluid, suggesting that the liquid CO2 must be derived from the hydrothermal fluid. While showing homogeneous δ13C, the hydrothermal fluids exhibit wide variation in gas contents. Active phase separation must be taking place within the conduits. Besides, H2‐depletion in the liquid CO2 suggests formation of solid CO2‐hydrate must also precede the venting of liquid CO2. In conclusion, liquid CO2 must be produced through following subseafloor processes: phase separation of hydrothermal fluid due to boiling, formation of solid CO2‐hydrate due to cooling of vapor phase, and melting of the solid CO2‐hydrate to liquid CO2 due to a temperature increase within the sedimentary layer.
Matching Data: Analyzing the Chronological Use Sequence in the Iron Age Necropolis of the Staggered Turriform of Son Ferrer (Balearic Islands, Spain)

The Son Ferrer archaeological site presents a series of successive occupations spanning a long period of time. At the beginning of the Iron Age (∼850 BC), a staggered turriform structure was built for a ritual purpose over an artificial hypogeum that had already been used as a collective necropolis during the Early Bronze Age (∼1800–1500 BC). Later, in the post-Talayotic phase (Second Iron Age, 550–123 BC), the hypogeum was again reused as a collective burial place. The present work is focused on the chronological and functional analysis of this last phase, which began ∼500 BC and ended ∼180 BC with the saturation and sealing of the hypogeum. The excavation process revealed that significant removal of archaeological material has occurred as a result of complex funerary space management practices, which generated a secondary archaeological context. Given this situation, and in order to establish the different use phases of the post-Talayotic necropolis, a dual strategy of excavation and research was implemented. First, an extensive series of radiocarbon dates on human remains (18 dates) was obtained, which were later analyzed following Bayesian strategies. Second, a detailed spatial analysis was carried out, georeferencing the location of all the archaeological finds. This strategy allowed the reconstruction of the space management processes and movement patterns that took place in the burial space. Despite some initial difficulties, the combination of these research strategies embedded in a contextual analysis provided both material and chronological references that have contributed to define the various use phases of the hypogeum.
Venezuela Basin crustal structure

Velocity-depth profiles derived from six two-ship expanding spread experiments, in combination with other geophysical data, define the characteristics of two distinct types of Venezuela Basin crust and the boundary between them. Each two-ship common midpoint reflection/refraction profile is automatically transformed into the τ-p plane, ‘picked’ and interpreted to provide V(Z) functions with appropriate confidence bounds. The results, together with gravity, magnetic, and near-vertical incidence reflection data, reveal a 50,000 km2 triangle of Venezuela Basin crust which resembles normal oceanic crust in a magnetic quiet zone. North and west of this triangle lies the previously defined, thick ‘Caribbean’ crust, having two distinct layers above the M discontinuity. Acoustic basement there appears unusually smooth due to extensive basaltic sills and flows which were cored at Deep Sea Drilling Project sites 146/149(sills), and 150 (flows); also, depths to mantle are greater than normal. Interpretations of near-vertical and wide-angle reflection data show that the extra crustal thickness is due not only to the emplacement of the flows but also to the crust below being somewhat thicker than normal. The boundary between the two crustal areas has a NE-SW trend which parallels the dominant structural and magnetic lineations.This boundary coincides in position, though not in trend, with the previously defined ‘central Venezuela Basin fault zone’. Further study is required to determine whether this boundary is of tectonic origin or if it represents a change in style of crustal production.
Prehistoric Stratigraphy of the Soufrière Hills–South Soufrière Hills Volcanic Complex, Montserrat, West Indies

The Soufrière Hills and South Soufrière Hills volcanoes are morphologically distinct but petrologically similar. The history of the complex is subdivided into seven episodes. The Soufrière Hills subunit I (≤175 ka) has deposits of Pelean style with ignimbrites of Plinian style abundant near its top. This is followed by deposits from the South Soufrière Hills (∼130 ka) that represent open‐crater St. Vincent–style activity. Soufrière Hills subunits II–V (∼112,000–∼400 BP) return to more characteristic Pelean activity; at ∼22,000 BP, block‐and‐ash flow deposits containing abundant clasts of vesicular andesite dominate. Age dating shows that renewed activity began just before European settlement in 1632 CE. This activity, including the ongoing eruption, is typical of the dominant eruptive style of this volcano for the last 175 ka.
Folsom Drought and Episodic Drying on the Southern High Plains from 10,900–10,200 14C yr B.P

Abstract The paleoenvironments of late Pleistocene and early Holocene time on the Southern High Plains have been studied for decades, but regionally extensive or long-term, easily recoverable proxy climate indicators are difficult to find. The stratigraphy of valley fill and upland eolian deposits and stable-carbon isotope data, in addition to geographically limited paleontological data, now provide clues to the environment during this time, which includes the earliest, or Paleoindian period (∼11,200–8000 14C yr B.P.) of human occupation. During the Clovis occupation (∼11,200–10,900 14C yr B.P.), valleys contained perennial streams. This was followed in Folsom time (10,900–10,200 14C yr B.P.) by an abrupt change to lakes and ponds (with water levels fluctuating between several meters depth and no surface water) and marshes and accumulation of sheet sands on uplands, starting the earliest phase of construction of the regional dune fields. These changing conditions indicate a shift from relatively wetter to relatively drier conditions with episodic drought. Stable-C isotopes further indicate that warming characterized the Clovis–Folsom transition. During the rest of the Paleoindian period the environment was relatively cool but fluctuated between wetter and drier conditions with an overall trend toward drying that resulted in further enlargement of the dune fields and culminated in the warm, dry Altithermal beginning ∼8000 14C yr B.P. Clovis time probably was the wettest of any Paleoindian period in terms of runoff and spring discharge. The Folsom period was drier and was the earliest episode of regional wind erosion and eolian deposition and may have been the warmest of Paleoindian times. Evidence of a previously hypothesized “Clovis drought” in this region is sparse.
A high-precision 40Ar/39Ar age for hydrated impact glass from the Dellen impact, Sweden

Abstract The dating of terrestrial impact craters and impact glasses that exhibit high degrees of mineralogical complexity can be problematic. However, if the maximum potential of the terrestrial impact crater record is to be realized, accurate and precise ages for crater-forming events are critical. Here we report a high-precision 40Ar/39Ar age for the Dellen impact structure, Sweden. Previous radio-isotopic constraints show a wide variation in age as a result of poor sample characterization and analytical approach. A detailed petrographical and mineralogical study provides a solid foundation for interpretation of step-heating 40Ar/39Ar data, culminating in a statistically robust age of 140.82±0.51 Ma (2σ; full external precision) for the Dellen impact event, for which data disfavour an inherited argon component. Primary hydration of the impact melt during cooling–quenching and entrapment of molecular water promoted rapid loss of inherited 40Ar from the impact melt of rhyolitic composition. Duplicate analyses of the water content and ∂D of the glass give similar values for the former (1.9±0.1 μmol mg−1) but unexpectedly low values for the latter (−159±8‰), with scatter beyond the expected analytical reproducibility due to isotopic heterogeneity. This study highlights that the 40Ar/39Ar technique is unrivalled in its ability to precisely and accurately date the products of hypervelocity collisional events. Supplementary material: Raw 40Ar/39Ar data are available at http://www.geolsoc. org.uk/SUP18633.
Long-term performance of contaminant barrier systems

This lecture describes the latest findings with respect to the long-term performance of modern municipal solid waste (MSW) landfill barrier systems. Field data relating to the clogging of leachate collection systems and the latest techniques for predicting their performance are examined. It is indicated that the primary leachate collection systems may have service lives that range from less than a decade to more than a century, depending on the design details, waste characteristics and mode of operation. Recent data indicate that landfill liner temperatures can be expected to reach at least 30–40°C for normal landfill operations. With recirculation of leachate the liner temperature increases faster than under normal operating conditions, and may be expected to exceed 40°C. Temperatures (up to 40–60°C) may occur at the base of landfills where there is a significant leachate mound. Temperature is shown to have a significant impact on both contaminant migration and the service life of the liner system. Field.
Provenance of the Late Quaternary sediments in the Andaman Sea: Implications for monsoon variability and ocean circulation

We present a geochemical and Sr‐Nd isotopic study on a sediment core collected from the Andaman Sea in an attempt to reconstruct the Late Quaternary weathering and erosion patterns in the watersheds of the river systems of Myanmar and understand their controlling factors. Age control is based on nine radiocarbon dates and δ18O stratigraphy. The rate of sedimentation was strongly controlled by fluctuations of the monsoon. We identify three major sediment provenances: (1) the Irrawaddy catchment, (2) the western slopes of the Indo‐Burman‐Arakan (IBA) mountain ranges and the Andaman Islands, and (3) the catchments of Salween and Sittang and the Bengal shelf, with the first two contributing 30–60% of the material. Enhanced contributions from juvenile sources and corresponding positive shifts of δ18O are observed at seven time periods (11–14, 20–23, 36, 45, 53, 57, and 62 ka) of which five are synchronous with cooling of the northern hemisphere, suggesting a link between the changes in sediment provenances and the shifting of the locus of the summer monsoon, southward from the Himalayas, without substantial reduction in intensity. Our data, and that from other cores in the region suggest that an eastward moving surface current disperses sediments, derived from the Bengal shelf and western margin of Myanmar, from the eastern Bay of Bengal into the western Andaman Sea and that its strength has increased since the LGM. The existence of this current during the LGM implies that the Andaman Sea and the Bay of Bengal were well connected during the last glacial period.
Sea spray emission from the surface of the open Baltic Sea

[1] Vertical aerosol flux values collected in the marine atmospheric boundary layer during Baltic cruises of the R/V Oceania have been analyzed. It has been determined that the aerosol emission from the sea surface in the open Baltic is proportional to the average energy dissipation rate raised to the 2/3 power. A similar relationship has been derived using dimensional analysis and a simple model of aerosol emission. It has been demonstrated that aerosol emission from the open Baltic may be parameterized using significant wave height and wind velocity.
Coupling of water and carbon fluxes via the terrestrial biosphere and its significance to the Earth's climate system

[1] Terrestrial water vapor fluxes represent one of the largest movements of mass and energy in the Earth's outer spheres, yet the relative contributions of abiotic water vapor fluxes and those that are regulated solely by the physiology of plants remain poorly constrained. By interpreting differences in the oxygen-18 and deuterium content of precipitation and river water, a methodology was developed to partition plant transpiration (7) from the evaporative flux that occurs directly from soils and water bodies (E d ) and plant surfaces (In). The methodology was applied to fifteen large watersheds in North America, South America, Africa, Australia, and New Guinea, and results indicated that approximately two thirds of the annual water flux from the "water-limited" ecosystems that are typical of higher-latitude regions could be attributed to T. In contrast to "water-limited" watersheds, where T comprised 55% of annual precipitation, T in high-rainfall, densely vegetated regions of the tropics represented a smaller proportion of precipitation and was relatively constant, defining a plateau beyond which additional water input by precipitation did not correspond to higher T values. In response to variable water input by precipitation, estimates of T behaved similarly to net primary productivity, suggesting that in conformity with small-scale measurements, the terrestrial water and carbon cycles are inherently coupled via the biosphere. Although the estimates of T are admittedly first-order, they offer a conceptual perspective on the dynamics of energy exchange between terrestrial systems and the atmosphere, where the carbon cycle is essentially driven by solar energy via the water cycle intermediary.
Fuzzy Optimization Neural Network Approach for Ice Forecast in the Inner Mongolia Reach of the Yellow River/Approche d'Optimisation Floue de Réseau de Neurones pour la Prévision de la Glace Dans le Tronçon de Mongolie Intérieure du Fleuve Jaune

Abstract In ice forecasting, a key problem is the forecast of freeze-up and break-up dates. Ice-water mechanics and the principle of heat-exchange were mainly adopted in previous research. However, the mathematical models in these studies are complex and many parameters are required in relation to upstream and/or downstream gauging stations. Moreover, too many assumptions or simplifications for these parameters and constraints directly lead to low accuracy of the models and limitations as to their practical applications. This paper develops a fuzzy optimization neural network approach for the forecast of freeze-up date and break-up date. The Inner Mongolia reach lies in the top north of the Yellow River, China. Almost every year ice floods occur because of its special geographical location, hydrometeorological conditions and river course characteristics. Therefore, it is of particular importance for ice flood prevention to forecast freeze-up date and break-up date accurately. A case study in this region shows that the proposed methodology may allow obtaining useful results.
USENIX Association Proceedings of MobiSys 2003 : The First International Conference on Mobile Systems , Applications , and Services

Smart Dust sensor networks – consisting of cubic millimeter scale sensor nodes capable of limited computation, sensing, and passive optical communication with a base station – are envisioned to fulfill complex large scale monitoring tasks in a wide variety of application areas. In many potential Smart Dust applications such as object detection and tracking, finegrained node localization plays a key role. However, due to the unique characteristics of Smart Dust, traditional localization systems cannot be used. In this paper we present and analyse the Lighthouse location systems, a novel laser-based location system for Smart Dust, which allows tiny dust nodes to autonomously estimate their location with high accuracy without additional infrastructure components besides a modified base station device. Using an early 2D prototype of the system, node locations could be estimated with an average accuracy of about 2% and an average standard deviation of about 0.7% of the node’s distance to the base station.
A scheme for process‐tagged SO4 and BC aerosols in NCAR CCM3: Validation and sensitivity to cloud processes

[1] A life cycle scheme for sulfate (SO4) and black carbon (BC) is implemented in an extended version of the National Center for Atmospheric Research (NCAR) Community Climate Model 3 (CCM3). The scheme includes emissions of dimethyl sulfide (DMS), SO2, and sulfate of natural and anthropogenic origins and emissions of BC from biomass burning and fossil fuel combustion. Chemistry and aerosol physics are parameterized based on prescribed oxidant levels and background aerosols of marine, continental, and polar origins. Aqueous chemistry depends on estimated exchange rate of cloudy and clear air. Particulate SO4 and BC are tagged by-production mechanisms for off-line reconstruction of aerosol optical and water activity properties. With emissions from International Panel on Climate Change (IPCC), calculations without feedback produce atmospheric turnover times (days) of 1.5 (SO2), 3.5 (SO4), and 4.7 (BC) for the year 2000 and 1.6 (SO2), 4.0 (SO4), and 4.7 (BC) for the year 2100 A2 emission scenario. The modeled SOx compounds compare within a factor 2 with observations at ground level in North America and Europe and for SO4 in the free troposphere. For BC, the ground-level concentrations are well within a factor 10 from observations over several regions. BC and SO4 are a factor 10 too low in Arctic winter, which can partly be linked to spurious low-level winter cloudiness. SO4 and BC are a factor 10 too high at ground-level low latitudes, and upper tropospheric SO2 is largely missing. These major model biases are caused by neglected transport and low scavenging efficiency in cumulus clouds. Cloud processes are discussed by sensitivity tests. SO4 and BC are found very sensitive to the vertical transport and scavenging in convective clouds. More research should aim at improved cloud parameterization schemes that address key processes associated with aerosols to reduce uncertainties associated with climate effects of anthropogenic aerosols.
Postoperative decreased levels of D-dimer in patients with gynecologic cancer with enoxaparin and fondaparinux thromboprophylaxis

The purpose of the present study was to evaluate the effects of enoxaparin (ENO) and fondaparinux (FPX) on postoperative plasma D-dimer levels and risk factors associated with postoperative venous thromboembolism (VTE) and pulmonary thromboembolism (PTE) in patients with gynecologic cancer. For this study, 434 patients with gynecologic cancer were recruited and a surgical treatment strategy was employed. Plasma D-dimer levels were measured prior to surgery, as well as on a schedule up to 3 weeks postoperatively and again after day 28. Patients with clinical signs and elevation of the plasma D-dimer level underwent multidetector row computed tomography. The D-dimer value was significantly lower in patients with ENO or FPX on postoperative days 3–10 compared to patients with gynecologic cancers who were not receiving ENO or FPX. The D-dimer value was significantly lower in patients with FPX compared to patients with ENO on postoperative days 5–7. The D-dimer value on postoperative day 3, the use of erythropoiesis-stimulating agents (ESAs), advancing age and non-O blood group were independent risk factors for postoperative VTE. The D-dimer value on postoperative day 3 and the use of ESAs were independent risk factors for postoperative PTE. The postoperative D-dimer value was significantly lower in patients with gynecologic cancer who were administered ENO or FPX compared to patients were not administered either ENO or FPX. The use of ESAs and high plasma D-dimer levels on postoperative day 3 were independent risk factors for postoperative VTE and PTE.