Miracle-dz/UniFAR-FTUs huggingface dataset:
Effects of Spatial Variability and Scale on Areally Averaged Evapotranspiration

This paper explores the effects of spatial variability and scale on areally averaged evapotranspiration. A spatially distributed water and energy balance model is employed to determine the effect of explicit patterns of land surface characteristics and atmospheric forcing on areally averaged evapotranspiration over a range of increasing spatial scales. The analysis is performed from the local scale to the catchment scale. The study area is King's Creek catchment, an 11.7 km2 watershed located on the native tallgrass prairie of Kansas. It is shown that a threshold scale, or representative elementary area (REA) exists for evapotranspiration modeling. It is shown further that the dominant controls on the scaling behavior of catchment-average evapotranspiration, and thus the size of the REA, depend on the dominant controls on its components (bare-soil evaporation, wet canopy evaporation, and dry canopy transpiration) and whether evapotranspiration is occurring at potential rates or soil- and vegetation-controlled rates. The existence of an REA for evapotranspiration modeling suggests that in catchment areas smaller than this threshold scale, actual patterns of model parameters and inputs may be important factors governing catchment-scale evapotranspiration rates in hydrological models. In models applied at scales greater than the REA scale, spatial patterns of dominant process controls can be represented by their statistical distribution functions. It appears that some of our findings are fairly general and will therefore provide a framework for understanding the scaling behavior of areally averaged evapotranspiration at the catchment and larger scales. Our results may have further implications for representing subgrid-scale land surface heterogeneity in hydrological parameterizations for atmospheric models.
Utilization of PET fiber and nanomaterial in concrete: Review of flexural concrete behavior

Concrete may gain maximum flexural strength to a certain percentage with the inclusion of plastic fiber. Because of the weakening bonding concerning the fiber and cement paste, it loses strength under compression at the same rate it gains. The optimal addition ratio must be established to add Polyethylene Terephthalate (PET) fiber to concrete to improve its mechanical and structural qualities. To decide what will change in the microstructure of the concrete and the traction link between the PET fiber’s surface, it is highly advised to use any nanomaterials with PET fibers. Concrete fabric’s characteristics may be enhanced with nanomaterials, thus increasing concrete brittle and proving its activity in case of combination with various fibers as composite materials. The high surface area for fine material can modify concrete texture, one of the properties which leads to increased compressive strength. So, there is a need to create more experimental research and analytical survey. All studies from 2010-2022 It has referenced.
Moisture and heat transport in hysteretic, inhomogeneous porous media: A matric head‐based formulation and a numerical model

A general, physically based formulation of water and energy transport in partially saturated soil must account for the coupling between the fields of matric potential ψ and temperature T. The formulation by de Vries (1958) is converted to one that employs ψ and T as the dependent variables. This conversion facilitates a significant generalization of the theory to accommodate the omnipresent complications of hysteresis and inhomogeneity. The limitations of the assumptions of local thermodynamic equilibrium are discussed. A finite element solution algorithm for the one-dimensional equations is outlined and tested on a variety of problems. The computational results demonstrate the reliability of the numerical model.
Structure and sharpness of phase transitions and mantle discontinuities

The structure of phase transitions expected from equilibrium thermodynamics is examined. We show that in binary systems, the shape of the coexistence region (phase loop) is controlled primarily by the partition coefficient K. We derive a general and simple one-parameter expression for the pressure dependence of the yield of the high-pressure phase and show that this function can be highly nonlinear: most of the transition occurs in a narrow interval near the boundary of the phase loop. Estimates of the effective width of binary phase transitions are less than half the total width of the coexistence region even for relatively mild partitioning (K < 1/4). We generalize these results to multiphase and multicomponent transitions. We show that the presence of nontransforming phases can affect the width of the transition substantially. We predict that the width of the olivine to wadsleyite transition in the presence of pyroxene and garnet is approximately half that of the binary phase loop at typical transition zone temperatures. The estimated effective width of this transition in the mantle (4-8 km) is marginally consistent with observations of high-frequency (0.5-1.0 Hz) P wave reflections from the 410 km discontinuity. We show that the effective width of the garnet to perovskite transition is sufficiently narrow to reflect S wave energy in the frequency range of ScS reverberations (10-40 mHz) and that this transition can account for the observed properties of the 710 km discontinuity.
Effects of adaxial and abaxial surface on the estimation of leaf chlorophyll content using hyperspectral vegetation indices

Vegetation indices are frequently used for the non-destructive assessment of leaf chemistry, especially chlorophyll content. However, most vegetation indices were developed based on the statistical relationship between the spectral reflectance of the adaxial leaf surface and chlorophyll content, even though abaxial leaf surfaces may influence reflectance spectra because of canopy structure or the inclination of leaves. In the present study, reflectance spectra from both adaxial and abaxial leaf surfaces of Populus alba and Ulmus pumila var. pendula were measured. The results showed that structural differences of the two leaf surfaces may result in differences in reflectance and hyperspectral vegetation indices. Among 30 vegetation indices tested, R672/(R550 × R708) had the smallest difference (4.66% for P. alba, 2.30% for U. pumila var. pendula) between the two blade surfaces of the same leaf in both species. However, linear regression analysis showed that several vegetation indices (R850 − R710)/(R850 − R680), VOG2, D730, and D740, had high coefficients of determination (R2 > 0.8) and varied little between the two leaf surfaces of the plants we sampled. This demonstrated that these four vegetation indices had relatively stable accuracy for estimating leaf chlorophyll content. The coefficients of determination (R2) for the calibration of P. alba leaves were 0.92, 0.98, 0.93, and 0.95 on the adaxial surfaces, and 0.88, 0.87, 0.88, and 0.92 on the abaxial surfaces. The coefficients of determination (R2) for the calibration of U. pumila var. pendula leaves were 0.85, 0.91, 0.86, and 0.90 on adaxial surface, and 0.80, 0.80, 0.84, and 0.88 on abaxial surface. These four vegetation indices were readily available and were little influenced by the differences in the two leaf surfaces during the estimation of leaf chlorophyll content.
Exchange of methane from rice fields: National, regional, and global budgets

Over the past decade, several estimates have been developed to establish source strengths of various atmospheric trace gases. Interest is, in part, driven by international agreements wherein governments are required to establish emission inventories and to develop means to stabilize or reduce national emissions. Although techniques and models for quantifying gas fluxes have improved considerably for some gases and sources, the uncertainties in the national, regional, and global budgets for a number of atmospheric compounds remain. In this paper, we review estimates of the emission of methane from rice fields both on a global scale and on a country scale, using China as an example. Several reported methods of obtaining an annual methane emission value for China are reviewed. A comparison among them yields a suggested emission value of 13.0±3.3 Tg yr−1 and a range from 9.7 to 16.2 Tg yr−1. Several strategies are suggested for future requirements to obtain greater accuracy in regional and country emission values.
DOAS measurements of formaldehyde and glyoxal above a south-east Asian tropical rainforest

Abstract. Tropical rainforests act as a huge contributor to the global emissions of biogenic volatile organic compounds (BVOCs). Measurements of their oxidation products, such as formaldehyde (HCHO) and glyoxal (CHOCHO), provide useful indicators of fast photochemistry occurring in the lower troposphere. However, measurements of these species in tropical forest locations are extremely limited. To redress this, HCHO and CHOCHO were measured using the long-path (LP) and multi-axis (MAX) differential optical absorption spectroscopy (DOAS) techniques above the rainforest canopy in Borneo during two campaigns in spring and summer 2008, as part of the Oxidant and Particle Photochemical Processes above a south-east Asian tropical rainforest (OP3) project. The results were compared with concurrent measurements of hydroxyl radical (OH), isoprene (C5H8) (which was the dominant organic species emitted in this forest environment), and various meteorological parameters. Formaldehyde was observed at a maximum concentration of 4.5 ppb and glyoxal at a maximum of 1.6 ppb, significantly higher than previous measurements in rural locations. A 1-D chemistry model was then used to assess the diurnal evolution of formaldehyde and glyoxal throughout the boundary layer. The results, which compare well with the LP-DOAS and MAX-DOAS observations, suggest that the majority of the glyoxal and formaldehyde is confined to the first 500 m of the boundary layer, and that the measured ratio of these species is reproduced using currently accepted product yields for the oxidation of isoprene by OH. An important conclusion is that the measured levels of glyoxal are consistent with the surprisingly high concentrations of OH measured in this environment.
Present‐day kinematics of Asia derived from geologic fault rates

Active fault geometry, available Quaternary rates on major faults, and the far-field plate motion are used to determine crustal kinematics in the collision zone between India and Asia. Using a finite element formalism to construct a spherical shell model of the Asian continent with embedded faults, we seek a velocity solution approaching the motion of rigid blocks by minimizing the elastic strain energy in the fault-bounded blocks. By doing so, we test the assumption that long-term deformation within continents is mostly localized into major faults. In the solution, fault motion accounts for more than 80% of the deformation, allowing us to describe our velocity model in terms of quasi-rigid block rotations on the sphere. South China is rotating clockwise about a pole located southwest of Borneo, implying an E-ESE velocity vector of ∼11 mm/yr for a point at Shanghai, in agreement with the velocity vector determined by very long baseline interferometry [Heki et al., 1995]. The eastward movement of south China is accommodated by oblique extension along the Red River fault at a rate of 10 ± 5 mm/yr in the south and by the combination of left-lateral strike-slip motion on the Qinling-Dabie Shan fault and the counterclockwise rotation of the Ordos and adjacent blocks in the north. The Tarim rotates clockwise with respect to Dzungaria about a pole located at 44°N, 92°E, consistent with increasing crustal shortening toward the west throughout the Tien Shan. Assuming incompressibility, a crustal volume budget over a domain encompassing the Tertiary mountain ranges in Asia shows that, over the last 10,000 years, 73 ± 4% of the north-south shortening between India and Asia has been absorbed by thickening of the lithosphere, and 27% has been accommodated by lateral extrusion of continental blocks. The present-day predominance of thickening in Asia results from the relatively slow eastward motion of south China, controlled by strike-slip faulting in the Qinling Shan and oblique extension in northeastern China.
Primitive oxygen-isotope ratio recorded in magmatic zircon from the Mid-Atlantic Ridge

Abstract The oxygen-isotope composition of the Earth’s upper mantle is an important reference for understanding mantle and crust geochemical cycles. Olivine is the most commonly used mineral for determining the influence of crustal processes on the oxygen-isotope ratio (δ18O) of primitive rocks, however it is an uncommon mineral in continental crust and readily alters at or near Earth’s surface. Here we report the first measurements of oxygen-isotope ratios in zircon from oceanic crust exposed at a mid-ocean ridge. Measurements of δ18O and trace elements were made by ion microprobe on zircon in polished rock chips of gabbro and veins in serpentinized peridotite drilled from the Mid-Atlantic Ridge. The zircon grains contain both oscillatory and sector growth zoning, features characteristic of magmatic zircon. Values of δ18O (zircon) = 5.3 ± 0.8‰ (2 st. dev., n = 68) for the population are consistent with the interpretation that these grains are igneous in origin and formed in high-temperature isotopic equilibrium with mantle oxygen. The δ18O values demonstrate that zircon in oceanic crust preserves primitive δ18O in spite of sub-solidus alteration of the whole rock. The fact that the primitive δ18O (zircon) values fall in a narrow range (5.3 ± 0.8‰) strengthens the use of oxygen isotopes in zircon as a tracer to identify processes of exchange in a wide range of modern and ancient crustal environments, including subducted oceanic crust (eclogite), and also in the oldest known pieces of Earth, >3900 million-year-old detrital zircon grains from Western Australia.
The comparison of spatial accessibility measures between non-obstacle and obstacle oriented based on gravity model

Spatial accessibility denotes the ease with which activities may be reached from a given location using a particular transportation system. There are a number of accessibility measures methods and models, such as time of access to city centre, mean travel costs and opportunity accessibility. But these methods or models ignore the existence of obstacles. In fact, there are many kinds of obstacles in the world, such as rivers, railways, etc. The paper reviews the progress of accessibility measures, and introduces the obstacle to the accessibility measures. Meanwhile, through the analysis of A* algorithm, the advantage of A* algorithm that could avoid obstacles is put forward. Based on the above mentioned, the obstacle oriented accessibility measures based on simple gravity model is discussed in details. Finally, a case study is fulfilled by comparison between the obstacle oriented and non-obstacle accessibility measures.
The Ocean's Overturning Circulation

The ocean is a mysterious place. As terrestrial creatures, we are familiar with a small volume of relatively warm ocean water near the surface. The deep ocean is not so familiar. Isolated from the thermal energy of the Sun and the mechanical energy of atmospheric winds, the deep ocean is completely dark and filled with near‐freezing water. Yet the deep ocean is far from stagnant. Radioactive tracer measurements show that the ocean's circulation brings its interior water into contact with the atmosphere every 600 years or so.
Unusual stratospheric transport and mixing during the 2002 Antarctic winter

Unusually large planetary wave activity in the 2002 Antarctic winter stratosphere weakened and warmed the polar vortex. Three minor warmings during August and early September preceded a late‐September major warming when the middle stratospheric zonal winds reversed to easterly and the polar temperature increased by an additional 25 K. Polar Ozone and Aerosol Measurement (POAM III) ozone data at high southern latitudes show unusually large variability in 2002 compared to previous POAM III years (1998–2001). Analyses of air parcel transport indicate this variability is caused by large‐scale isentropic transport. Diagnostics of transport and mixing show that during the major warming the lower stratospheric vortex remained intact, while the middle stratospheric vortex split into two pieces; one piece rapidly mixed with extravortex air, while the other returned to the pole as a much weaker and smaller vortex.
EOLIAN-AQUATIC DEPOSITS AND FAUNAS OF THE MIDDLE CAMBRIAN POTSDAM GROUP

Abstract Exposures of the middle Cambrian Potsdam Group of northern New York, including the type section, represent a suite of interfingering eolian dune and aquatic deposits that record the activities of early land-going arthropods. Quartz arenites at these exposures are dominantly fine to medium grained, well sorted, and have hematite-coated well-rounded, high-sphericity quartz grains characterized by secondary optically continuous quartz cement overgrowths. Eolian beds are laminated and dominated by m- to dm-scale foresets characterized by large-scale, laterally extensive cross-beds that dip >∼15°–34° and contain reverse-graded lamination, en-echelon microfaulted slumps, adhesion structures, and very high ripple-index asymmetric ripples that lie on the foresets with crests that trend downdip. Lower parts of foresets are interpreted as toesets, and contain unusual Diplichnites and Protichnites trackways, which record the uphill, downhill, crest-parallel, and switchback-style movement of arthropods in dry or damp sand. Trackways that ascend dune faces do not possess a medial tail drag, whereas trackways that descend do, and turns of trackways often have deep continuous medial impressions; these features suggest arthropods leaned into the slope when turning downhill in dry sand. More shallowly dipping (∼4°–15°) cross-beds are interpreted as bottomsets. Like nearby intertidal Potsdam deposits, these beds contain Protichnites trackways and Arenicolites burrows. Paleocurrent analyses imply a coastline in which offshore and mixed-direction winds moved dunes seaward. Considered together, these strata record migration of coastal dunes into aquatic environments and flooding and reworking of distal dune bottomsets. In this setting, the same suite of epifaunal arthropods inhabited dry, damp, and aquatic marine environments.
Finite volume model for two-dimensional shallow water flows on unstructured grids

A numerical model based upon a second-order upwind finite volume method on unstructured triangular grids is developed for solving shallow water equations. The HLL approximate Riemann solver is used for the computation of inviscid flux functions, which makes it possible to handle discontinuous solutions. A multidimensional slope-limiting technique is employed to achieve second-order spatial accuracy and to prevent spurious oscillations. To alleviate the problems associated with numerical instabilities due to small water depths near a wet/dry boundary, the friction source terms are treated in a fully implicit way. A third-order total variation diminishing Runge-Kutta method is used for the time integration of semidiscrete equations. The developed numerical model has been applied to several test cases as well as to real flows. Numerical tests prove the robustness and accuracy of the model.
Segmentation and morphology of open water bodies from multispectral images

A number of problems in remote sensing require the segmentation of specific spectral classes such as water bodies, clouds or forested areas. Further analysis of these classes may include the calculation of optical reflectance values such as chlorophyll concentration, absolute reflectivity or vegetation indices. To derive reliable measurements of these variables, a precise segmentation − from the rest of the image − of the spectral classes is needed. In this work, we propose a new methodology to segment open water bodies based on a variant of principal component analysis (PCA). In this variant, information about the spectral class model of the water bodies to be separated in the feature space is required. This information is input by means of a training field encircling a set of pixels representative of this spectral model. A training field for land cover is also defined. This PCA variant produces two sets of multispectral bands, one for water bodies and one for land cover types. The first two bands of each set are input into a fuzzy clustering procedure. By using a merging process, the clusters are merged into two classes: water bodies and the rest of the image. From this, a logic bitmap image is obtained. The pixels of the bitmap consist of ON for water bodies and OFF for the rest of the image. The bitmap is then used to obtain morphological parameters of the water bodies.
The "Business-As-Usual" growth of global primary energy use and carbon dioxide emissions – historical trends and near-term forecasts

Abstract. We analyse the global primary energy use and total CO2 emissions time series since 1850 and show that their relative growth rates appear to exhibit periodicity with a fundamental timescale of ~60 years and with significant harmonic behaviour. Quantifying the inertia inherent in these dynamics allows forecasting of future "business as usual" energy needs and their associated CO2 emissions. Our best estimates for 2020 are 800 EJ yr−1 for global energy use and 14 Gt yr−1 for global CO2 emissions, with both being above almost all other published forecasts. This suggests the energy and total CO2 emissions landscape in 2020 may be significantly more challenging than currently envisaged.
Edaphic controls on soil organic carbon retention in the Brazilian cerrado : Soil structure

Soil structure can be an important factor affecting soil organic carbon (SOC), but it is also a dynamic property affected by texture, mineralogy, land use, soil fauna, and also SOC. Assuming that structure affects SOC mostly by occlusion of particulate organic matter (POM) within aggregates, it was hypothesized that structure exerts a major control on SOC retention in soils of the Brazilian Cerrado region. Water-stable aggregates (WSA) were obtained from the 1-m depth of three different-textured, uncultivated soils. The mean weight diameter (MWD) of WSA was used as a structural indicator, and SOC concentrations were determined in intact WSA and their respective sand fractions (estimating occluded POM). Clay + silt content in bulk soils was correlated with MWD in all depths but more strongly in the top 10 cm. Although equally correlated with clay + silt contents, SOC concentrations were well correlated with MWD only in the 0- to 5-cm layer. Sand-free SOC concentrations in WSA fractions were proportional to sand content, indicating that the SOC dilution effect reported in particle size fractionations occurs naturally in the soil fabric. Occlusion of POM within aggregates was proportional to clay + silt contents, but this did not result in larger total POM pools, and the weak correlations obtained did not warrant predictive models. Aggregates produced by macrofauna comprised a minor but significant part of the soil and were mostly SOC enriched. We concluded that the structural control on SOC retention is less significant than the textural and mineralogical controls, since aggregation depends on those properties and is not as strongly correlated with SOC concentration and POM occlusion.