bluuebunny/crossref_metadata_2025_split huggingface dataset:
Assessing Alpine Ecosystem Dynamics over the Great Himalayan Mountain Range, Kashmir: Earth Observation and Ecosystem Modeling
Authors: Bashir Subiaya 
Published: February 2021

Abstract
The alpine vegetation distribution in the Greater Himalaya, Kashmir is preseted and its projected behavior under changing climate using LANDSAT TM (2002) and LANDSAT-8 (2014) data, mapped at 1:30000 scale and having spatial resolution of 30 m. The alpine vegetation in the region spans ~2990 km2. SRTM DEM was used to delineate the spatial extents of the alpine landscapes (&gt;2500 m asl). A total of nine land use classes which include Alpine pasture, Alpine scrubs, bare land, dense forest, exposed rocks, lakes, rivers, snow and sparse forest were identified in the area. The results reflect both positive and negative changes in all classes over time. Alpine pastures have increased 60.11 km2 followed by Alpine scrubs, which have increased by 54.70 km2. Exposed rocks have reduced to 29.22 km2, while sparse forests have diminished by 23.62 km2. Bare land has decreased by 14.64 km2 and snow has declined by 2.04 km2. Lakes in the area have shrunk by 0.84 km2 and river by 0.02 km. The overall observed results revealed that Alpine pastures have increased by 17% followed by Alpine scrubs to 15%. The future climate projections from Worldclim (RCP 8.5) and other environmental data used in the MaxEnt model suggest increase in the suitable habitat for the shrub species by the mid of 21st century.
Prediction of Flood in Barak River using Hybrid Machine Learning Approaches: A Case Study
Authors: Sahoo Abinash , Samantaray Sandeep , Ghose Dillip K 
Published: February 2021

Abstract
Flooding causes several threats with outcomes which include peril to human and animal life, damage to property, and adversity to agricultural fields. Therefore, flood prediction is of prime importance for reducing loss of life and devastation to property. To model complex nature of hydrologic processes artificial neural network (ANN) tool is effectively being utilized for modelling different nonlinear relationships, and has proved to be an appropriate method for flood prediction. Present study investigated relative accuracy of radial basis function neural network (RBFNN) and support vector machine (SVM) models combined with Firefly Algorithm (FA) in predicting river flood discharge and contrasted with that of regular ANN, RBFNN and SVM models. Monthly river flow data of Silchar and Dholai stations located in Cachar district of Assam, India are utilized for the present study. For assessing model performance, coefficient of determination (R2), mean square error (MSE) and root mean square error (RMSE) were measured. Evaluation of outcomes shows that both RBF-FA (radial basis function - firefly algorithm) and SVM-FA (support vector machine - firefly algorithm) hybrid models give more precise forecasting results than RBFNN, FFBPNN (feed forward back propagation neural network) and SVM models. Yet, it can be observed that SVM-FA model give better forecasting outputs with R2 value 0.9818 than RBF-FA model. Results also reveal that simple SVM model performs marginally better than simple ANN model.
Groundwater quality assessment using water quality index (WQI) under GIS framework
Authors: Ram Arjun , Tiwari S. K. , Pandey H. K. , Chaurasia Abhishek Kumar , Singh Supriya , Singh Y. V. 
Published: February 2021

AbstractGroundwater is an important source for drinking water supply in hard rock terrain of Bundelkhand massif particularly in District Mahoba, Uttar Pradesh, India. An attempt has been made in this work to understand the suitability of groundwater for human consumption. The parameters like pH, electrical conductivity, total dissolved solids, alkalinity, total hardness, calcium, magnesium, sodium, potassium, bicarbonate, sulfate, chloride, fluoride, nitrate, copper, manganese, silver, zinc, iron and nickel were analysed to estimate the groundwater quality. The water quality index (WQI) has been applied to categorize the water quality viz: excellent, good, poor, etc. which is quite useful to infer the quality of water to the people and policy makers in the concerned area. The WQI in the study area ranges from 4.75 to 115.93. The overall WQI in the study area indicates that the groundwater is safe and potable except few localized pockets in Charkhari and Jaitpur Blocks. The Hill-Piper Trilinear diagram reveals that the groundwater of the study area falls under Na+-Cl−, mixed Ca2+-Mg2+-Cl− and Ca2+-$${\text{HCO}}_{3}^{ - }$$

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types. The granite-gneiss contains orthoclase feldspar and biotite minerals which after weathering yields bicarbonate and chloride rich groundwater. The correlation matrix has been created and analysed to observe their significant impetus on the assessment of groundwater quality. The current study suggests that the groundwater of the area under deteriorated water quality needs treatment before consumption and also to be protected from the perils of geogenic/anthropogenic contamination.
Heat Stress Indicators in CMIP6: Estimating Future Trends and Exceedances of Impact‐Relevant Thresholds
Authors: Schwingshackl Clemens , Sillmann Jana , Vicedo‐Cabrera Ana Maria , Sandstad Marit , Aunan Kristin 
Published: February 2021

AbstractGlobal warming is leading to increased heat stress in many regions around the world. An extensive number of heat stress indicators (HSIs) has been developed to measure the associated impacts on human health. Here we calculate eight HSIs for global climate models participating in the Coupled Model Intercomparison Project Phase 6 (CMIP6). We compare their future trends as function of global mean temperature, with particular focus on highly populated regions. All analyzed HSIs increase significantly (p < 0.01) in all considered regions. Moreover, the different HSIs reveal a substantial spread ranging from trends close to the rate of global mean temperature up to an amplification of more than a factor of two. Trends change considerably when normalizing the HSIs by accounting for the different scales on which they are defined, but the large spread and strong trends remain. Consistently, exceedances of impact‐relevant thresholds are strongly increasing globally, including in several densely populated regions, but also show substantial spread across the selected HSIs. The indicators with the highest exceedance rates vary for different threshold levels, suggesting that the large indicator spread is associated both to differences in trend magnitude and the definition of threshold levels. These results highlight the importance of choosing indicators and thresholds that are appropriate for the respective impact under consideration. Additionally, further validation of HSIs regarding their capability to quantify heat impacts on human health on regional‐to‐global scales would be of great value for assessing global impacts of future heat stress more reliably.
Neutral Wind Dynamics Preceding the STEVE Occurrence and Their Possible Preconditioning Role in STEVE Formation
Authors: Liang Jun , Zou Y. , Nishimura Y. , Donovan E. , Spanswick E. , Conde M. 
Published: February 2021

AbstractStrong Thermal Emission Velocity Enhancement (STEVE) is a nightsky optical phenomenon of great research interest in recent years. Recent findings indicated that STEVE likely represents certain extremely intensified chemiluminescence airglow instead of traditional aurora. In this study, we investigate the patterns and variations of the neutral wind and temperature before the STEVE emergence using joint scanning Doppler imager (SDI 630 nm) and optical all‐sky imager (ASI) observations, and make an initial effort to explore the potential preconditioning role of neutral winds in the STEVE production. Neutral winds enhance in westward and southward directions following substorm auroral intensification, and show an equatorward propagating trend from auroral latitudes. However, in STEVE events the enhanced equatorward winds feature a steep stop/reversal at certain subauroral latitude, and strong wind convergence is developed there. This pattern sustains for ∼15–20 min, and then STEVE arises at about this stop latitude. The strength of the southward wind intensification and wind convergence is in general weaker or absent in nonSTEVE substorm events. We propose that enhanced equatorward winds may transport relevant neutrals species that are key to the STEVE airglow production to subauroral latitudes, and pile up at the stop latitude of the equatorward winds due to the strong convergence there. Such a transport/pileup effect led by the neutral winds may prepare a reservoir of neutral constituent which, when further aided by subauroral ion drift, leads to a dramatic increase of the airglow production and the STEVE occurrence.
Seismic Imaging of the Crust Beneath Arunachal Himalaya
Authors: Singh Arun , Saikia Dipankar , Kumar M. Ravi 
Published: February 2021

AbstractWe present the first high‐resolution seismic images of the crust beneath the Arunachal Himalaya, using 22,525 high quality teleseismic receiver functions (RFs). Data from 32 broadband seismic stations deployed in the Arunachal Himalaya during 2010–2016 is used for this purpose. In addition, data from the HIMNT, SIKKIM, Hi‐CLIMB, and Geodynamics ANd Seismic Structure of the Eastern‐Himalaya Region networks are used to investigate along strike variations in the crustal architecture of the Eastern Himalayan mountain belt. Common Conversions Point stacks constructed using RFs from 203 seismic stations along various S‐N profiles reveal lateral variations in the crustal structure. We observe, (a) a less complex crust beneath the Arunachal Himalaya compared to that in the Nepal and Sikkim Himalaya (b) a highly deformed layer running parallel to the Main Himalayan Thrust (c) intermittent anisotropic low velocity layer in the middle crust (d) that the crustal thickness estimates are in close agreement with those in other segments of the Eastern Himalaya (40–60 kms) (e) no prominent signatures of a mid‐crustal ramp as observed in the Nepal Himalaya. The geometry of the crust in the Eastern Himalayan segments appears less complex compared to the Central Himalayan segments. The presence of strong anisotropy associated with the low velocity layer at depths of 20–30 km suggests a mechanically weak middle crust beneath Arunachal Himalaya. Attributing these anisotropic signatures to the channel flow model appears contentious.
The Role of Air–Sea Interactions in Atmospheric Rivers: Case Studies Using the SKRIPS Regional Coupled Model
Authors: Sun Rui , Subramanian Aneesh C. , Cornuelle Bruce D. , Mazloff Matthew R. , Miller Arthur J. , Ralph F. Martin , Seo Hyodae , Hoteit Ibrahim 
Published: February 2021

AbstractAtmospheric rivers (ARs) play a key role in California's water supply and are responsible for most of the extreme precipitation and major flooding along the west coast of North America. Given the high societal impact, it is critical to improve our understanding and prediction of ARs. This study uses a regional coupled ocean–atmosphere modeling system to make hindcasts of ARs up to 14 days. Two groups of coupled runs are highlighted in the comparison: (1) ARs occurring during times with strong sea surface temperature (SST) cooling and (2) ARs occurring during times with weak SST cooling. During the events with strong SST cooling, the coupled model simulates strong upward air–sea heat fluxes associated with ARs; on the other hand, when the SST cooling is weak, the coupled model simulates downward air–sea heat fluxes in the AR region. Validation data shows that the coupled model skillfully reproduces the evolving SST, as well as the surface turbulent heat transfers between the ocean and atmosphere. The roles of air–sea interactions in AR events are investigated by comparing coupled model hindcasts to hindcasts made using persistent SST. To evaluate the influence of the ocean on ARs we analyze two representative variables of AR intensity, the vertically integrated water vapor (IWV) and integrated vapor transport (IVT). During strong SST cooling AR events the simulated IWV is improved by about 12% in the coupled run at lead times greater than one week. For IVT, which is about twice more variable, the improvement in the coupled run is about 5%.
Control of the Interactions Between Stream and Groundwater by Permafrost and Seasonal Frost in an Alpine Catchment, Northeastern Tibet Plateau, China
Authors: Ma Rui , Sun Ziyong , Chang Qixin , Ge Mengyan , Pan Zhao 
Published: February 2021

AbstractWhile the individual effects of permafrost and seasonal frost on the interactions between groundwater and surface water have received much attention, few attempts have been made to investigate the effects of permafrost and seasonal frost together on groundwater flow and its interactions with surface water. In this study, hydraulic, chemical, and isotopic data as well as a Bayesian mixing model were employed to investigate the interactions between streams and groundwater, the contributions of groundwater to the mainstream, and their relationships to the distribution of permafrost and seasonal frost in a representative subcatchment in the headwater region of the Heihe River Basin on the northeastern Qinghai‐Tibet Plateau in China. Our results showed that due to the freezing and thawing of recharge water sources and soils, the groundwater flow and stream flux from the permafrost zone to the seasonal frost zone increased during the thawing period, with maximum values in thawed period, and decreased during the frozen period. These variations affected groundwater recharge in the seasonal frost zone, resulting in dynamic changes in the groundwater table and the hydraulic gradient between the recharge and discharge points in the seasonal frost zone during the different freeze‐thaw periods. Correspondingly, the contribution of groundwater to the mainstream discharge decreased from 95% during the frozen period to 80%–90% during the thawing period. It then decreased to ∼40%–60% of the mainstream discharge during the thawed period and increased to ∼70%–90% during the refreezing period. From the permafrost zone to the seasonal frost zone and the catchment outlet, the aquifers in the piedmont plain of the seasonal frost zone play an important role in maintaining streamflows by switching their hydrological functions, that is, slowly releasing groundwater to maintain the streamflow during the frozen period and rapidly transferring the groundwater to mainstream during the thawed period.
High‐Resolution Observations of Turbulence Distributions Across Tropopause Folds
Authors: Söder Jens , Zülicke Christoph , Gerding Michael , Lübken Franz‐Josef 
Published: February 2021

AbstractIn this study, we interpret two vertical turbulence measurements. We acquired these uninterrupted high‐resolution dissipation rate profiles with the balloon‐borne instrument LITOS (Leibniz Institute Turbulence Observations in the Stratosphere) from velocity measurements using a spectral technique. The meteorological situation is characterized using ECMWF’s integrated forecast system (IFS) as breaking Rossby waves showing significant tropospheric jets and a developed tropopause fold. In both cases, dissipation rates in the shear zone above the upper‐tropospheric jet are three orders of magnitude larger than below, reaching severe turbulence strengths (1,000 mW kg−1) in a deep tropopause fold and moderate turbulence strengths in a medium tropopause fold (10 mW kg−1). These turbulent spots are shown to create a tripole shaped pattern of PV modification across the tropopause. Furthermore, tracer‐tracer correlations exhibit mixing of tropospheric and stratospheric air masses in the medium‐fold case. While the strength of turbulence corresponds to the depth of the tropopause fold, its asymmetric vertical distribution is possibly related to the tropopause fold life cycle. The observed asymmetry in the vertical turbulence distribution is consistent across both tropopause folds and in overall agreement with measured Richardson numbers. In the medium‐fold case however, it is neither expected from conceptual models nor from Richardson numbers in the IFS. This calls for further field campaigns to investigate the role of turbulence and its implications for the meteorological understanding as well as for aviation safety.
Observational Validation of Parameterized Gravity Waves From Tropical Convection in the Whole Atmosphere Community Climate Model
Authors: Alexander M. J. , Liu C. C. , Bacmeister J. , Bramberger M. , Hertzog A. , Richter J. H. 
Published: February 2021

AbstractTropical gravity waves that are generated by convection are generally too small in scale and too high in frequency to be resolved in global climate models, yet their drag forces drive the important global‐scale quasi‐biennial oscillation (QBO) in the lower stratosphere, and models rely on parameterizations of gravity wave drag to simulate the QBO. We compare detailed properties of tropical parameterized gravity waves in the Whole Atmosphere Community Climate Model version 6 (WACCM6) with gravity waves observed by long‐duration superpressure balloons and also compare properties of parameterized convective latent heating with satellite data. Similarities and differences suggest that the WACCM6 parameterizations are excellent tools for representing tropical gravity waves, but the results also suggest detailed changes to the gravity wave parameterization tuning parameter assumptions that would bring the parameterized waves into much better agreement with observations. While WACCM6 currently includes only nonstationary gravity waves from convection, adding gravity waves generated by the steady component of the heating that are stationary relative to moving convective rain cells is likely to improve the simulation of the QBO in the model. The suggested changes have the potential to alleviate common biases in simulated QBO circulations in models.
Icefield Breezes: Mesoscale Diurnal Circulation in the Atmospheric Boundary Layer Over an Outlet of the Columbia Icefield, Canadian Rockies
Authors: Conway J. P. , Helgason W. D. , Pomeroy J. W. , Sicart J. E. 
Published: February 2021

AbstractAtmospheric boundary layer (ABL) dynamics over glaciers mediate the response of glacier mass balance to large‐scale climate forcing. Despite this, very few ABL observations are available over mountain glaciers in complex terrain. An intensive field campaign was conducted in June 2015 at the Athabasca Glacier outlet of Columbia Icefield in the Canadian Rockies. Observations of wind and temperature profiles with novel kite and radio‐acoustic sounding systems showed a well‐defined mesoscale circulation developed between the glacier and snow‐free valley in fair weather. The typical vertical ABL structure above the glacier differed from that expected for “glacier winds”; strong daytime down‐glacier winds extended through the lowest 200 m with no up‐valley return flow aloft. This structure suggests external forcing at mesoscale scales or greater and is provisionally termed an “icefield breeze.” A wind speed maximum near the surface, characteristic of a “glacier wind,” was only observed during night‐time and one afternoon. Lapse rates of air temperature down the glacier centerline show the interaction of down‐glacier cooling driven by sensible heat loss into the ice, entrainment and periodic disruption and warming. Down‐glacier cooling was weaker in “icefield breeze” conditions, while in “glacier wind” conditions, stronger down‐glacier cooling enabled large increases in near‐surface temperature on the lower glacier during periods of surface boundary layer (SBL) disruption. These results raise several questions, including the impact of Columbia Icefield on the ABL and melt of Athabasca Glacier. Future work should use these observations as a testbed for modeling spatio‐temporal variations in the ABL and SBL within complex glaciated terrain.
Main Group Supramolecular Chemistry Led to Surprising New Directions in the Self-Assembly of Organic Macrocycles, Cages, and Cyclophanes
Authors: Johnson Darren W. , Shear Trevor A. 
Published: February 2021

AbstractCyclophanes are an admirable class of macrocyclic and cage compounds that often display unusual properties due to their high strain and unusual conformations. However, the exploration of new, complex cyclophanes has been encumbered by syntheses that can be low yielding, require harsh reaction conditions, and arduous purification steps. Herein, we discuss our work using metalloid-directed self-assembly and dynamic covalent chemistry to form cryptands. These were then subjected to mild conditions to produce discrete disulfide, thioether and hydrocarbon macrocycles in high yields. ‘Design of Experiments’ was then used to selectively synthesize targeted macrocycles from complex mixtures.1	Introduction2	Cryptands to Cyclophanes3	Functionalizable Macrocycles4	‘Design of Experiments’ Targeted Synthesis5	Conclusions and Outlook
Transcriptome Profiling Reveals the Endogenous Sponging Role of LINC00659 and UST-AS1 in High-Altitude Induced Thrombosis
Authors: Jha Prabhash Kumar , Vijay Aatira , Prabhakar Amit , Chatterjee Tathagata , Nair Velu , Bajaj Nitin , Kumar Bhuvnesh , Sharma Manish , Ashraf Mohammad Zahid 
Published: February 2021

Abstract
Background The pathophysiology of deep vein thrombosis (DVT) is considered as multifactorial, where thrombus formation is an interplay of genetic and acquired risk factors. Little is known about the expression profile and roles of long noncoding RNAs (lncRNAs) in human subjects developing DVT at high altitude.
Methods Using RNAseQ, we compared peripheral blood mRNA and lncRNA expression profile in human high-altitude DVT (HA-DVT) patients with high-altitude control subjects. We used DESeq to identify differentially expressed (DE) genes. We annotated the lncRNAs using NONCODE 3.0 database. In silico putative lncRNA–miRNA association study unravels the endogenous miRNA sponge associated with our candidate lncRNAs. These findings were validated by small-interfering RNA (siRNA) knockdown assay of the candidate lncRNAs conducted in primary endothelial cells.
Results We identified 1,524 DE mRNAs and 973 DE lncRNAs. Co-expressed protein-coding gene analysis resulted in a list of 722 co-expressed protein-coding genes with a Pearson correlation coefficients >0.7. The functional annotation of co-expressed genes and putative proteins revealed their involvement in the hypoxia, immune response, and coagulation cascade. Through its miRNA response elements to compete for miR-143 and miR-15, lncRNA-LINC00659 and UXT-AS1 regulate the expression of prothrombotic genes. Furthermore, in vitro RNA interference (siRNA) simultaneously suppressed lncRNAs and target gene mRNA level.
Conclusion This transcriptome profile describes novel potential mechanisms of interaction between lncRNAs, the coding genes, miRNAs, and regulatory transcription factors that define the thrombotic signature and may be used in establishing lncRNAs as a biomarker in HA-DVT.