Miracle-dz/UniFAR-FTUs huggingface dataset:
Relating Precipitating Ice Radiative Effects to Surface Energy Balance and Temperature Biases Over the Tibetan Plateau in Winter

Substantial underestimation of the ice water path, surface radiative fluxes, and surface temperature is identified from the Coupled Model Inter‐comparison Project phase 5 models over the boreal winter Tibetan Plateau. It is found that the cold bias is controlled by the biases of surface radiative fluxes, and the underestimated ice water path has significant contribution to the radiation biases. In addition, after removing the impact of snow albedo feedback, the relation between the biases of residual surface temperature and ice water path can be revealed. A set of sensitivity experiments with fully coupled Community Earth System Model version 1 (CESM1) is performed to identify the impact of the precipitating ice radiative effect on biases of the surface energy budget and temperature. When this effect is turned off, more solar radiation can penetrate through the optically thin atmosphere, while much less downward longwave radiation owing to missing of emission from falling snow. The high spatial coherency between the changes in surface radiation budget and surface temperature suggests that the cold bias over the Tibetan Plateau could be partly attributed to deficiency of the total downward radiative flux due to the lack of precipitating ice. The inclusion of the precipitating ice radiative effect can reduce the model biases of surface radiative fluxes and surface temperature.
Tracing Radiation and Architecture of Canopies TRAC MANUAL Version 2.1

The leaf area index (LAI) and the Fraction of Photosynthetically Active radiation (FPAR) absorbed by plant canopies are biophysical parameters required in many ecological and climate models. In spite of their importance, the commercially available techniques for measuring these quantities are often less than adequate. Many studies have relied on commercial instruments such as the LAI-2000 Plant Canopy Analyzer (LI-COR), AccuPAR Ceptometer (Decagon), and Demon as well as hemispherical photography. However, these optical instruments have been repeatedly found to underestimate LAI of forests and discontinuous canopies where the spatial distribution of foliage elements is not random. TRAC was developed to cope with this problem.
The Global Distribution of Lunar Light Plains From the Lunar Reconnaissance Orbiter Camera

We present the first globally consistent map of lunar light plains from Lunar Reconnaissance Orbiter Camera mosaics 100 m/pixel. Based on this map, ~70% of light plains are likely related to the Orientale and Imbrium basins; however, many light plains deposits originated with local‐ and regional‐scale impacts, nonmare volcanics (i.e., the Apennine Bench Formation), as well as ancient impact melt deposits that lack diagnostic small‐scale features. Compositional evidence suggests that the light plains associated with basins (i.e., Cayley plains) form through substantial mixing with local materials, implying that ballistic sedimentation is a primary formation mechanism. Based on the distribution of light plains with respect to the Orientale and Imbrium basins, the stratigraphic extent of an individual basin extends to at least four basin radii. As such, the South Pole‐Aitken basin modified at least 80% of the lunar surface. This work suggests that the entire lunar surface was modified to varying degrees at the time of large basin formation. This has implications for sample interpretations because any highland site within four radii of a large basin could potentially contain primary basin material or more local material that was redeposited by secondaries, neither of which is necessarily representative of the terrain upon which they are found.
Final Closure Time of the Paleo‐Asian Ocean: Implication from the Provenance Transformation from the Yangjiagou Formation to Lujiatun Formation in the Jiutai Area, NE China

The Jiutai area is tectonically situated at the eastern segment of the Central Asian Orogenic Belt (CAOB) and is close to the North China Craton (NCC) to the south, serving as an ideal place to investigations of the closure of the Paleo‐Asian Ocean (PAO). Sandstone samples collected from the Yangjiagou Formation and the Lujiatun Formation in this area have been studied in detail in terms of petrology, geochronology and geochemistry. The maximum depositional time of the Yangjiagou and Lujiatun formations has been constrained to early Middle Triassic (ca. 245 Ma) and middle Late Triassic (ca. 219 Ma), respectively. The Yangjiagou Formation, with a major provenance of dissected island arcs, is dominantly composed of Phanerozoic sediments from Northeastern China (NE China) massifs. The Lujiatun Formation, with major sediments from active continental margins, has a relatively larger proportion of Precambrian sediments, in which the ∼1.85 Ga and ∼2.5 Ga sediments are typical of the crystalline basements of the NCC and NE China massifs, which were uplifted and eroded during the closure of the PAO. Besides, both formations show the enrichment in LREEs and the depletion in HREEs, the common Eu negative anomalies, and trace element contents similar to that of the upper continental crust. Based on the provenance analysis of these two formations, the final closure time of the PAO in this area is constrained as from the early Middle Triassic (ca. 245 Ma) to the middle Late Triassic (ca. 219 Ma).
Discrete Element Modeling of Railway Ballast for Studying Railroad Tamping Operation

The dynamic behavior of ballast particles during track tamping is studied by developing a computer simulation model using the Discrete Element Model (DEM) method. The simulation model is developed in a commercially available DEM software called PFC3D (Particle Flow Code 3D). The study primarily evaluates a complete tamping cycle as defined by insertion, squeeze, hold, and withdrawal. Using a Taguchi approach, the effect of Tine motion’s frequency and amplitude, insertion velocity, and squeeze velocity are evaluated on tamping effectiveness. The compactness of the ballast particles, as defined by the average number of contacts per particle (referred to “Coordination Number”) is used as a measure of the effectiveness of tamping. Setting up the DEM model and important elements such as selection and calibration of particle shapes, ballast mechanical properties, contact model, and parameters governing the contact force models are described in detail. The tamping process is evaluated using a half-track layout with a highly modular code that enables a high degree of adjustability to allow control of all parameters for improved simulation flexibility. A parametric study is performed to find the best values of tine motion parameters for improving tamping efficiency. A performance comparison is made between linear and elliptical tamping. The results indicate that smaller squeeze and release velocities of the tines yield better compaction. Of course, reducing the velocities would result in increased tamping time. Additionally, the results indicate that the linear motion of the tines potentially result in better compaction than elliptical motion, although the latter may require less insertion force (power) and cause less ballast damage.
Radiocarbon age offsets of Plants and Bioclasts in the Holocene Sediments from the Miyazaki Plain, Southeast Coast of Kyushu, Southwest Japan

Abstract To investigate the relationship between paleoenvironmental changes and marine reservoir effects, the radiocarbon ages of marine bioclasts and terrestrial plants from the same horizons of a sediment core in the Holocene Epoch were measured. This core, with a length of approximately 9 m, was obtained from the southern part of the Miyazaki Plain southeast of Kyushu Island, which faces the Kuroshio warm current. This drilling site is located in an uplift area associated with the subduction of the Philippine Sea Plate. Based on analyses of lithology, molluscan and foraminifera assemblages, and radiocarbon dating, we interpreted four sedimentary units in order of age: tidal flat, inner bay, Kikai-Akahoya volcanic ash, and delta plain. These paleoenvironmental changes were mainly associated with the sea-level rise during the deglacial period. The reservoir ages of nine pairs from the tidal flat to inner bay facies were found to be from the time span of 7300–8200 cal BP. The chronological changes in the reservoir effect are correlated with those seen in Holocene sediments of the other coastal area in East Asia.
RESEARCH OF WHEEL-RAIL WEAR DUE TO NON-SYMMETRICAL LOADING OF A FLAT CAR

Purpose . The paper is aimed at determining the influence of non-symmetrical loading of a flat car on the magnitude of the wear factor of a wheel-rail pair when changing the operation parameters that occur in operation. Methodology . The dynamic loading of the flat car, model 13-401 with typical three-piece bogies is studied using a model of spatial oscillations of a five-car coupling with the help of mathematical and computer simulation. Theoretical calculations are performed for the most dangerous sections of the railway track – small and medium radius curves in the range of permissible speeds. Findings . The indicators of wear of the rolling stock wheels and the rails are analysed on the example of flat cars in the presence of a longitudinal and transverse displacement of the load mass centre relative to the car symmetry centre. To obtain information on the effect of permissible deviations of the arrangement of cargo in the car on the magnitude of the dynamic loading of the wheel-rail contact, the authors performed theoretical studies of the spatial variations of the rail carriage and its interaction with the track. Originality . To determine the wear of the wheel-rail pair, the effect of displacement in two directions from the central axis of symmetry of the load gravity centre was studied, taking into account the value of the travel speed along the curved sections of the small and medium radius using a mathematical model of coupling of five freight cars. Practical value . As a result of the theoretical studies carried out, the authors assessed such factors as wear factor, directional force, and hunting of the wheel set of freight rolling stock in the event of load gravity centre displacement when moving along curved sections of the railway track. To establish the possible cause of intensive wear of the wheels and rails, the following parameters were analysed: lozenging of front bogie side frames; hunting of the left side frame of the front bogie; mutual longitudinal movement of the side frame and axle box of the front wheel set; mutual hunting of the left side frame of the bogie relative to the front wheel set.
Rapid Late Quaternary Slip, Repeated Prehistoric Earthquake Rupture, and Widespread Landsliding Associated With the Karakudzhur Thrust, Central Kyrgyz Tien Shan

Field studies have shown that active faulting in the SW Tien Shan is distributed across a series of E‐W reverse faults along the range fronts and within basin interiors, with summed shortening rates that are consistent with GPS measurements. In contrast, few field studies have been undertaken to determine the distribution, and the average slip rates, of faults in the central and eastern parts of the Tien Shan. In this paper we use remote and field‐based observations to characterize the active faulting and tectonic geomorphology of the Karakudzhur Basin in the central Tien Shan of Kyrgyzstan. We use radiocarbon, luminescence, and uranium series dating to provide ages on three fluvial terraces that are vertically displaced across the basin‐bounding reverse fault and estimate fault slip rates using a 20°S dipping fault exposure. We find that the fault has a slip‐rate of ∼2.4–5.9 mm/year averaged over the Holocene, indicating that it accommodates a major part of the shortening measured by GPS. In contrast to the relatively uniform distribution of N‐S shortening in the SW Tien Shan, significant shortening may instead be concentrated at present on a few active faults in the northern part of the central Tien Shan. The fresh geomorphic expression of the Karakudzhur fault suggests that it has ruptured in recent prehistory in a large‐magnitude Mw ≥ 7 earthquake. From palaeoseismic trenching we show that two significant surface rupturing earthquakes have occurred since ~2.4 ka. The most recent earthquake was potentially accompanied by widespread landsliding and faulting in the surrounding highlands.
High-resolution seismic imaging reveals infill history of a submerged Quaternary fjord system in the subantarctic Auckland Islands, New Zealand

Abstract Quaternary processes and environmental changes are often difficult to assess in remote subantarctic islands due to high surface erosion rates and overprinting of sedimentary products in locations that can be a challenge to access. We present a set of high-resolution, multichannel seismic lines and complementary multibeam bathymetry collected off the eastern (leeward) side of the subantarctic Auckland Islands, about 465 km south of New Zealand's South Island. These data constrain the erosive and depositional history of the island group, and they reveal an extensive system of sediment-filled valleys that extend offshore to depths that exceed glacial low-stand sea level. Although shallow, marine, U-shaped valleys and moraines are imaged, the rugged offshore geomorphology of the paleovalley floors and the stratigraphy of infill sediments suggests that the valley floors were shaped by submarine fluvial erosion, and subsequently filled by lacustrine, fjord, and fluvial sedimentary processes.
A Novel Hybrid Enhanced Oil Recovery Method by Smart Water-Injection and Foam-Flooding in Carbonate Reservoirs

This contribution focuses on recovery of oil by using a newly hybrid Enhanced Oil Recovery (EOR) method, which combines smart water (i.e. ionically modified brine) and foam flooding of light oil with dissolved carbon dioxide at high pressure in carbonate reservoirs. Ionically modified brine (i.e. low salinity) has a dual improvement effect. It not only leads to more stable foam lamellae, but also helps to change the carbonate rock wettability from oil-wet to more water-wet, which has for some conditions more favorable relative permeability behavior. The mechanism for the modified permeability behavior in the presence of ionically modified brine is only partly understood. Therefore, we use the DLVO (i.e. Derjaguin, Landau, Verwey, and Overbeek) theory (i.e. which considers double layer repulsion, born repulsion, and Van der Waals attraction) and surface complexation modeling to better understand the mechanism(s) of ionically modified brine as wettability modifier and foam stabilizer. We use the PHREEQC software to obtain the equilibrium concentrations and surface potential and to study the effect of salinity and carbon dioxide gas pressure for a given choice of the surfactant (i.e. carboxylic acid R-COOH). It is conjectured that high carbon dioxide pressures have a destabilizing effect on the film, as they reduce the surface potential. A reduced surface potential leads to a decreasing electrostatic double layer repulsion and thus destabilizes the stability of the foam film, whereas low salinity leads to less screening of the surface potential and thus improves the stability of the foam film. The low-salinity flow is characterized by a high residual oil saturation and low end-point permeability for the two-phase oil-water flow. For the calcite surface an enhanced stability help to stabilize the water film on the calcite surface if the oil-water surface charge has the same sign as the surface charge on the calcite surface. Our calculations show the pH range where the sign of these charges is the same or opposite at low-salinity and high-salinity conditions. Admittedly, these calculations only show trends, but can be used to delineate optimal conditions for the use of combined Smart Water Assisted Foam (SWAF) flooding.
The influence of flame and furnace soldering method on the stress corrosion, fatigue resistance and fracture toughness of soldered bar attachment systems for implant overdentures

ABSTRACT The purpose of the study was to investigate the influence of flame and furnace soldering methods on the stress corrosion, fatigue resistance and fracture toughness of a ‘Dolder’ bar soldered to a non-oxidising gold cylinder using a gold solder. Two bars were soldered to opposite sides of a cylinder using the two techniques. Fatigue cycling one side of the bars was undertaken, with one group in a wet corrosive environment and the other in air. Force displacement load-unload curves was established to 100 N as a base line, thereafter, every 1000 cycles to 100 N load for 10,000 cycles. The system compliance and energy loss (mJ), was calculated. The critical stress intensity factor, K1c, of the solder/cylinder interface was established using a single-edge-notched-beam test. Mode of failure was evaluated using SEM. No corrosion was observed in the wet environment. Both soldering methods produced a thin brittle diffusion layer within the surface of the cylinder. The K1c of this layer was similar to that of a brittle ceramic. No embrittling reaction occurred at the solder/bar junction. This interfacial reaction has clinical relevance for soldered bar attachment systems using non-oxidising cylinders.
RAINFALL VARIABILITY AND TREND ANALYSIS IN MAKURDI METROPOLIS BENUE STATE, NIGERIA

This study analyses Makurdi rainfall data from 1955 to 2015, for the purpose of detecting the rainfall variability, trends, and assessing its implications on flood occurrence. Data on daily rainfall and flood occurrences were collected from relevant government agencies. Rainfall trends were analyzed using MannKendall, Spearmans rank correlation and Students t tests, both giving almost similar results for the three methods. Rainfall variability was analyzed using standardized precipitation index (SPI). The result of the analysis indicated that 1955 and 1993 were the wettest years, while 1958 and 2003 were the driest. Also, September was the wettest, closely followed by August, while December was the driest. A negative (decreasing) statistically insignificant trend for the total annual rainfall data from 1955 to 2015, but positive (increasing) statistically insignificant trend for the extreme annual rainfall was observed. The findings revealed that extreme rainfall events corresponded to flood occurrence. Thus, the annual rainfall total is not necessarily an important cause of increased flood frequency, but the fraction of it that occurs as extreme rainfall. It is recommended that effective mitigation measures should be put in place for likely floods that may arise owing to the anticipated extreme rainfall magnitudes in the coming years in Makurdi.
East Asian Study of Tropospheric Aerosols and their Impact on Regional Clouds, Precipitation, and Climate (EAST‐AIRCPC)

Aerosols have significant and complex impacts on regional climate in East Asia. Cloud‐aerosol‐precipitation interactions (CAPI) remain most challenging in climate studies. The quantitative understanding of CAPI requires good knowledge of aerosols, ranging from their formation, composition, transport, and their radiative, hygroscopic, and microphysical properties. A comprehensive review is presented here centered on the CAPI based chiefly, but not limited to, publications in the special section named EAST‐AIRcpc concerning (1) observations of aerosol loading and properties, (2) relationships between aerosols and meteorological variables affecting CAPI, (3) mechanisms behind CAPI, and (4) quantification of CAPI and their impact on climate. Heavy aerosol loading in East Asia has significant radiative effects by reducing surface radiation, increasing the air temperature, and lowering the boundary layer height. A key factor is aerosol absorption, which is particularly strong in central China. This absorption can have a wide range of impacts such as creating an imbalance of aerosol radiative forcing at the top and bottom of the atmosphere, leading to inconsistent retrievals of cloud variables from space‐borne and ground‐based instruments. Aerosol radiative forcing can delay or suppress the initiation and development of convective clouds whose microphysics can be further altered by the microphysical effect of aerosols. For the same cloud thickness, the likelihood of precipitation is influenced by aerosols: suppressing light rain and enhancing heavy rain, delaying but intensifying thunderstorms, and reducing the onset of isolated showers in most parts of China. Rainfall has become more inhomogeneous and more extreme in the heavily polluted urban regions.
Climate Trends of Temperature, Precipitation and River Discharge in the Abbay River Basin in Ethiopia

Projecting future changes of streamflow in the Abby River Basin (ARB) is important for planning and proper management of the basin system. The current study conducted in five stations of the Abbay river basin, and investigated the annual temperature, precipitation, and river discharge variability using the Innovative trend analysis method, Mann-Kendall, and Sen’s slope test estimator. The result showed a slightly increasing trend of annual precipitation in Assoa (Z = 0.71), Bahir Dar (Z = 0.13), and Gonder (Z = 0.26) stations, while a significant increasing trend was observed in Nedgo (Z = 2.45) and Motta (Z = 1.06) stations. Interestingly, the trend of annual temperature in Assosa (Z = 5.88), Bahir Dar (Z = 3.87), Gonder (Z = 4.38), Nedgo (Z = 4.77), and Motta (Z = 2.85) was abruptly increased. The average mean temperature has increased by 0.2°C in the past 36 years (1980 to 2016). The extreme high temperature was observed in the semi-dry zone of northern Ethiopia. During the study period, a significant declining trend of the river discharge was recorded, and the river discharge was sharply decreased from 1992 onwards. The results of the current study showed annual variability of river discharge, precipitation, and temperature of the study area of the basin that could be used as a basis for future studies.
Effect of Fe3+ on Phase Relations in the Lower Mantle: Implications for Redox Melting in Stagnant Slabs

Recent studies have revealed that Earth's deep mantle may have a wider range of oxygen fugacities than previously thought. Such a large heterogeneity might be caused by material subducted into the deep mantle. However, high‐pressure phase relations are poorly known in systems including Fe3+ at the top of the lower mantle, where the subducted slab may be stagnant. We therefore conducted high‐pressure and high‐temperature experiments using a multi‐anvil apparatus to study the phase relations in a Fe3+‐bearing system at 26 GPa and 1573–2073 K, at conditions prevailing at the top of the lower mantle. At temperatures below 1923 K, MgSiO3‐rich bridgmanite, an Fe3+‐rich oxide phase, and SiO2 coexist in the recovered sample. Quenched partial melt was observed above 1973 K, which is significantly lower than the solidus temperature of an equivalent Fe3+‐free bulk composition. The partial melt obtained from the Fe3+‐rich bulk composition has a higher iron content than coexisting bridgmanite, similar to the Fe2+‐dominant system. The results suggest that strong mantle oxygen fugacity anomalies might alter the subsolidus and melting phase relations under lower mantle conditions. We conclude that (1) a small amount of melt may be generated from an Al‐depleted region of a stagnant slab, such as subducted former banded‐iron‐formation, and (2) Fe3+ is not transported into the deep part of the lower mantle because of its incompatibility during melting.