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Spatiotemporal variability/stability analysis of NO_(2),CO,and land surface temperature(LST)during COVID-19 lockdown in Amman city,Jordan

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Geo-Spatial Information Science 2023年第3期26卷 540-557页

作者： Ali Almagbile Khaled Hazaymeh Department of Geography Applied Geoinformatics LaboratoryYarmouk UniversityIrbidJordan

The massive lockdown of human socioeconomic activities and vehicle movements due to the COVID-19 pandemic in 2020 has resulted in an unprecedented reduction in pollutant gases such as Nitrogen Dioxide(NO_(2))and Carbon Monoxide(CO)as well as Land Surface Temperature(LST)in Amman as well as all countries around the *** this study,the spatial and temporal variability/stability of NO_(2),CO,and LST throughout the lockdown period over Amman city have been *** NO_(2) and CO column density values were acquired from Sentinel-5p while the LST data were obtained from MODIS satellite during the lockdown period from 20 March to 24 April in 2019,2020,and *** statistical analysis showed an overall reduction in NO_(2) in 2020 by around 27% and 48% compared to 2019 and 2021,***,an increase of 7% in 2021 compared to 2019 was observed because almost all anthropogenic activities were allowed during the *** temporal persistence showed almost constant NO2 values in 2020 over the study area throughout the lockdown *** addition,a slight decrease in CO(around 1%)was recorded in 2020 and 2021 compared to the same period in *** on human activities resulted in an evident drop in LST in 2020 by around 13%and 18% less than the 5-year average and 2021 *** study concludes that due to the restrictions imposed on industrial activities and automobile movements in Amman city,an unprecedented reduction in NO_(2),CO,and LST was recorded.

关键词： Air quality COVID-19 lockdown spatiotemporal analysis NO_(2) CO Land Surface Temperature(LST) Sentinel-5p and MODIS satellites

A procedural footprint enhancement of global topographic surface with multiple levels of detail

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International Journal of Digital Earth 2020年第4期13卷 527-545页

作者： Lukáš Brůha Jan Kolář Faculty of Science Department of Applied Geoinformatics and CartographyCharles University in PraguePragueCzech Republic Grifinor Project CopenhagenDenmark

Virtual globes are technologies for visual navigation through a threedimensional,multi-resolution model of the entire *** representations used in virtual globes,however,lack geometric flexibility at high-resolution levels of the planet-wide terrain *** is a problem especially if boundaries between individual geospatial features and the terrain are important.A novel integration of individual polygonal boundaries with a specific multi-resolution representation of the planet-wide terrain is developed in this *** the preparation stage,the integration relies on an original simplification algorithm applied to the polygonal boundaries between geospatial features and the *** output is a multiple level-of-detail(LOD)geometry,which can be combined with a known multi-LOD representation of the terrain that uses run-time *** data representation is suitable for storage in existing database systems,avoids any data redundancy across LODs,and is even independent of the subdivision schema that partitions the planet’s surface for the sake of dealing with *** runtime,a novel reconstruction algorithm stitches geometric parts from different LODs together in a manner that augments the multi-LOD representation of the *** a certain proximity range from a given position,the method reconstructs a scene that preserves topological relations between the boundaries of geospatial features with the *** method also guarantees that certain nearest proximity to the given position consists of the best geometries that correspond to the original *** properties of the method close up the gap between a mere exploratory visualization of static,pre-generated models and the models supporting geospatial analysis,which is deemed crucial for applications in Geographic Information Systems,Building Information Modelling and other software industries.A prototype implementation and experiment results that prove this method are also prese

关键词： Feature-based topography multiple level-of-detail procedural modeling vector data organization geometry reconstruction

Assessment of GNSS zenith tropospheric delay responses to atmospheric variables derived from ERA5 data over Nigeria

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Satellite Navigation 2023年第1期4卷 167-182,I0005页

作者： Ifechukwu Ugochukwu Nzelibe Herbert Tata Timothy Oluwadare Idowu Department of Surveying and geoinformatics Federal University of Technology AkureAkureNigeria

Tropospheric delay is a major error caused by atmospheric refraction in Global Navigation Satellite System(GNSS)*** study evaluates the potential of the European Centre for Medium-range Weather Forecast(ECMWF)Reanalysis 5(ERA5)atmospheric variables in estimating the Zenith Tropospheric Delay(ZTD).Linear regression models(LRM)are applied to estimate ZTD with the ERA5 atmospheric *** ZTD are also estimated using standard ZTD models based on ERA5 and Global Pressure and Temperature 3(GPT3)atmospheric *** ZTD estimates are evaluated using the data collected from the permanent GNSS continuously operating reference stations in the Nigerian *** results reveal that the Zenith Hydrostatic Delay(ZHD)from the LRM and the Saastamoinien model using ERA5 surface pressure are of identical accuracy,having a Root Mean Square(RMS)error of 2.3 mm while the GPT3-ZHD has an RMS of 3.4 *** the Zenith Wet Delay(ZWD)component,the best estimates are derived using ERA5 Precipitable Water Vapour(PWV).These include the ZWD derived by the LRM having an average RMS of 20.9 mm and Bevis equation having RMS of 21.1 mm and 21.0 mm for global and local weighted mean temperatures,*** evaluation of GPT3-ZWD estimates gives RMS of 45.8 *** study has provided a valuable insight into the application of ERA5 data for ZTD *** line with the fndings of the study,the ERA5 atmospheric variables are recommended for improving the accuracy in ZTD estimation,required for GNSS positioning.

关键词： ECMWF reanalysis 5(ERA5) Global navigation satellite systems(GNSS) Global pressure and temperature 3(GPT3) Modelling Nigeria Zenith tropospheric delay(ZTD)

Efficiency of local minima and GLM techniques in sinkhole extraction from a LiDAR-based terrain model

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International Journal of Digital Earth 2019年第9期12卷 1067-1082页

作者： Péter Enyedi Melinda Pap Zoltán Kovács László Takács-Szilágyi Szilárd Szabó a Department of Physical Geography and geoinformatics University of DebrecenDebrecenHungary Internet of Things Research Institute Eszterházy Károly University of Applied SciencesEgerHungary

The aim of this paper was to study reliable automated delineationpossibilities of karst sinkholes using a LiDAR-based digital terrain model(DTM) with pixel-based classifications. We applied two approaches toextract sinkholes: (1) general linear modeling (GLM) with morphometricindices derived from DTM;(2) and a local minima-based delineationusing only LiDAR DTM as the input layer. The outcome of the localminima was significantly different from the reference ones but found allthe sinkholes without previous knowledge of the area. The GLM-basedoutcome did not differ statistically from the reference. Results showedthat these approaches were efficient in detecting sinkholes based onLIDAR derivatives, and can be used for risk assessment and hazardpreparedness in karst areas: GLM had an overall accuracy of 89.5% andlocal minima had an accuracy of 92.3%;both methods identifiedsinkholes but also had commission errors, identifying depressions assinkholes.

关键词： Karst mapping sinkhole identification general linear model statistical evaluation sink fill

Early warning and disaster management:the importance of geographic information(Part B)

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International Journal of Digital Earth 2010年第3期3卷 313-315页

作者： Guest Editors Milan Konecny Wolfgang Reinhardt Laboratory on geoinformatics and Cartography Institute of Geography Faculty of Science Masaryk UniversityKotlarska 261137 BRNOCzech Republic AGIS geoinformatics Lab Institute of Applied Computer Science(INF4)University of the BundeswehrMu¨nchenGermany

This special issue is part of a double special issue(Part A was published in the previous issue of this journal)dealing with the role of Geographic Information(GI)for Early Warning(EW)and Disaster Management(DM).In the editorial of Part A we gave an introduction to the topic focussing on initiatives from the EU and China and we have highlighted the importance of Digital Earth for EWand *** have also reflected on the outcome of some events organized by the guest editors which were important for the topic and for this special issue.

关键词： journal disaster Early

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Landslide inventory validation and susceptibility mapping in the Gerecse Hills, Hungary

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Geo-Spatial Information Science 2021年第3期24卷 498-508页

作者： Dávid Gerzsenyi Gáspár Albert Department of Cartography and geoinformatics Eötvös Loránd UniversityBudapestHungary

Landslides pose a threat to property both in the populated and cultivated areas of the Gerecse Hills (Hungary). The currently available landslide inventory database holds the records from many sites in the area, but the database is out-of-date. Here we address the problem of revising the National Landslides Cadastre landslide inventory database by creating a landslide suscept-ibility map with a multivariate model based on likelihood ratio functions. The model is applied to the TanDEM-X DEM (0.4″ res.), the current landslide inventory of the area, and data acquired from geological maps. By comparing the distributions of four variables in the landslide and non-landslide area with grid computation methods, the model yields landslide susceptibility estimates for the study area. The estimations show to what extent a certain area is similar to the sample areas, therefore, its likelihood to be affected by landslides in the future. The accuracy of the model predictions was checked in the field and compared to the results of our previous study using the SRTM-1 DEM for a similar analysis. The model gave accurate estimates when certain correction measures were applied to the input datasets. The limitations of the model, the input datasets, and the suggested correction measures are also discussed.

关键词： Landslide susceptibility landslide inventory TanDEM-X Gerecse Hills landslides geomorphometry

Generating high-resolution climatological precipitation data using SinGAN

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Big Earth Data 2023年第1期7卷 81-100页

作者： Yang Wang Hassan A.Karimi geoinformatics Laboratory School of Computing and InformationUniversity of PittsburghPittsburghUSA

High-resolution(HR)climate data are indispensable for studying regional climate trends,disaster prediction,and urban development planning in the face of climate ***,state-of-the-art long-term global climate simulations do not provide appropriate HR climate *** learning models are often used to obtain high-resolution climate ***,due to the fact that these models require sufficient low-resolution(LR)and HR data pairs for the training process,they cannot be applied to scenario with inadequate training *** this paper,we explore the applicability of a single image generative adversarial network(SinGAN)in generating HR climate *** relies on single LR input data to obtain the corresponding HR *** improve the performance for extreme-value regions,we propose a SinGAN combined with the weighted patchGAN discriminator(WSinGAN).The proposed WSinGAN outperforms comparable models in generating HR precipitation data,and its results are close to real HR data with sharp gradients and more refined small-scale *** also test the scalability of the pre-trained WSinGAN for unseen samples and show that although only a single LR sample is used to train WSinGAN,it can still produce reliable HR data for unseen data.

关键词： Climate downscaling SinGAN deep learning adversarial training

Source identification of nitrate in the upper aquifer system of the Wadi Shueib catchment area in Jordan based on stable isotope composition

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Journal of Arid Land 2021年第4期13卷 350-374页

作者： Mutawakil OBEIDAT Muheeb AWAWDEH Noor AL-KHARABSHEH Ahmad AL-AJLOUNI Faculty of Science and Arts Jordan University of Science and TechnologyIrbid 22110Jordan Laboratory of applied geoinformatics Department of Earth and Environmental SciencesYarmouk UniversityIrbid 21163Jordan Department of Water Resources and Environmental Management Al-Balqa Applied UniversityAl-Salt 19117Jordan

Groundwater forms the main freshwater supply in arid and semi-arid areas,and contamination of this precious resource is complicated by the slow rate of recharge in these *** contamination of groundwater is a global water quality problem,as it entails threat to human health as well as aquatic *** identification of contamination is the cornerstone and a prerequisite for any effective management program of water *** isotope composition of the dissolved nitrate(δ^(15)N-NO_(3)-andδ^(18)O-NO_(3)-)has been applied to identify NO_(3)-sources and the main transformation processes in the upper aquifer system(A1/2,A4,and B2/A7 aquifers)in the Wadi Shueib catchment area,***,the stable isotope compositions of the groundwater(δ^(2)H-H_(2)O andδ^(18)O-H_(2)O)in conjunction with the groundwater hydrochemistry were integrated to investigate the origin and evolution of the *** revealed that groundwater in the study area is fresh and hard-very hard water,and mainly a Ca-Mg-Cl ***_(3)-concentration was in the range of 7.0-74.0 mg/L with an average of 37.0 mg/*** of the samples showed concentration higher than the natural background concentration of NO_(3)-(5.0-10.0 mg/L).Theδ^(2)H-H_(2)O andδ^(18)O-H_(2)O values indicated that the groundwater is meteoric,and of Mediterranean origin,with a strong evaporation ***δ^(15)N-NO_(3)-values ranged between 6.0‰and 11.3‰with an average of 8.7‰,and theδ^(18)O-NO_(3)-values ranged between 1.6‰and 5.9‰with an average of 3.4‰.These values are in conformity with the stable isotope composition of nitrate derived the nitrification of wastewater/manure,and soil *** and denitrification are the main transformation processes affecting nitrogen *** analysis revealed no significant differences in theδ^(2)H-H_(2)O andδ^(18)OH_(2)O values,andδ^(15)N-NO_(3)-andδ^(18)O-NO_(3)-values for the three aquifers(A1/2,A4,and B2/A7),indicating that the groundwater of

关键词： δ^(15)N-NO_(3)– δ^(18)O-NO_(3)– nitrate sources pollution meteoric origin aquifer Jordan

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环境地球物理学:新概念(英文)

地学前缘 2001年第1期8卷 47-57页

作者： GueliS.Vakhromeev Department of applied Geophysics and geoinformatics

环境地球物理学是勘探地球物理学新科学和新应用分支。环境地球物理定义为用仪器对以各种物理场形式出现的物质和能量进行测量进而对环境进行多重目的监控。环境地球物理再细分为灾害、防护及医学环境地球物理。对环境物理异常及其天然... 详细信息

环境地球物理学是勘探地球物理学新科学和新应用分支。环境地球物理定义为用仪器对以各种物理场形式出现的物质和能量进行测量进而对环境进行多重目的监控。环境地球物理再细分为灾害、防护及医学环境地球物理。对环境物理异常及其天然和人工源进行了整理、分类。文中说明了地质生态目标和过程的静态和动态物理地质模型系统 ,以及多元建模原则。环境地球物理场的变化可作为地质环境演变部分或全部丧失其稳定性乃至被破坏的明显标志 ,且意义重大。灾害事件 (地震、滑坡、海震等 )的预报被证明是可能的。这些灾祸是各种技术因素或触发地质过程的结果 ,它们发展潜隐而发生突然 ,正如缓发生态地质炸弹一样。

关键词：环境地球物理学灾害地球物理防护地球物理医学地球物理地质生态目标