Review on status of groundwater database and application prospect in deep-time digital earth plan

Groundwater is an important water resource.The total amount of active groundwater in a hydrological cycle is about 3.5 times that of the total amount of surface water.The information in the deep groundwater records the material exchange and dynamics in the earth’s evolution,which is an important aspect of the Deep-Time Digital Earth(DDE)plan.In recent years,scientists have discussed the distribution of transboundary aquifers and the environmental significance of groundwater resources through groundwater databases established by international organizations,such as the Global Groundwater Information System and the chronicles consortium,and national institutes,such as national geological surveys.The application of the groundwater database in the DDE plan,however,has been limited by the management,interactivity,and monitoring method of the groundwater data.The ability to further integrate data that are private and scattered across research institutions and individuals,while establishing an open,unified,and shared groundwater data platform,is essential to enhance our understanding of groundwater,ranging from shallow to deep water,which is a goal of the DDE plan.In this study,we introduced the current situation of groundwater database operations in domestic and international research and provided frontier research with groundwater big data.Considering the related objectives of the DDE plan and the limitations of existing groundwater databases,we proposed an improvement plan and new prospects for applying groundwater databases in the research of the deep earth.

Digital earth, Virtual Reality and urban seismic disaster simulation

US Vice President Al Gore's vision of Digital Earth applies us with prospects for brand-new ways of solving problems the earth is facing such as seismic disaster. ms paper first briefly introduces the concept of Digital Earth. Then in the context of Digital Earth. the Origin, concept and application of Virtual Reality technology are reviewed. After that we present in detail our preliminary case study--CVR-USD (Computer Virtual Reality for Urban Seismic Disaster Simulation) System which aims to simulate and manage seismic disaster through integrating RS, GIS and VR technologies. For this system, we've built USD subsystem, developed SMVR software to implement CVR. and also developed a Spatial Dare Analysis Package to handle spatial data related to earthquake disaster.

“Digital earth” in support of an online oceanic educational public service and popularization

According to the initial vision of ＂digital earth＂ （DE）, the public should constitute a significant proportion of its users. However, to date, most of the studies and applications have focused on science, the private sec- tor and government. A DE-supported online oceanic educational public service and popularization system, iOcean, is studied. First, the vision for the public＇s engagement with ＂digital ocean＂ is described： an analysis is presented from four aspects, i.e., the space dimension, the time dimension, the state dimension and its relationship with human beings. Second, the technical framework of iOcean is discussed, including data updating and model computing, the data, the function, and the application layers. Third, two key technolo- gies are studied in detail that will enable the construction of iOcean. More than half a million public viewers have used the current version＇s website. Practical demonstrations show that iOcean can bring virtual oceans to web browsers and desktops and construct a bridge between government departments and the general public.

A comprehensive and up-to-date web-based interactive 3D emergency response and visualization system using Cesium Digital Earth: taking landslide disaster as an example

As with the fast advances in the technologies of big Earth data and information communication,Web-based 3D GIS system has come a long way from a few years ago.These advances reflect in many aspects of 3D GIS such as higher real-time performance,enhanced interactivity,more realistic 3D visualization effect and improved user interface.This paper aims to present a comprehensive and upto-date 3D Web GIS for Emergency Response using the current vue.js web application framework and the well-known Cesium APl,taking landslide disaster as an example.Building upon recent advances in WebGL technology,we developed a suite of enhanced 3D spatial analysis functions,including interactive route planning,instant text/image/video messaging being incorporated into both 3D WebGL page and mobile GIS applications,and progressive 3D construction and AR visualization using LiDAR and camera over local emergency network or internet.Moreover,professional functions such as landslide susceptibility mapping,landslide monitoring,spatial temporal contingency plan management,landslide information management,personnel and equipment management,and communication are all implemented and integrated in the 3D GIS system.Most of the functions of the system are implemented using open-source projects,which is beneficial to the development of the 3D GIS research community.

Digital earth:yesterday,today,and tomorrow

The concept of Digital Earth(DE)was formalized by Al Gore in 1998.At that time the technologies needed for its implementation were in an embryonic stage and the concept was quite visionary.Since then digital technologies have progressed significantly and their speed and pervasiveness have generated and are still causing the digital transformation of our society.This creates new opportunities and challenges for the realization of DE.‘What is DE today?’,‘What could DE be in the future?’,and‘What is needed to make DE a reality?’.To answer these questions it is necessary to examine DE considering all the technological,scientific,social,and economic aspects,but also bearing in mind the principles that inspired its formulation.By understanding the lessons learned from the past,it becomes possible to identify the remaining scientific and technological challenges,and the actions needed to achieve the ultimate goal of a‘Digital Earth for all’.This article reviews the evolution of the DE vision and its multiple definitions,illustrates what has been achieved so far,explains the impact of digital transformation,illustrates the new vision,and concludes with possible future scenarios and recommended actions to facilitate full DE implementation.

Think global,cube local:an Earth Observation Data Cube’s contribution to the Digital Earth vision

The technological landscape for managing big Earth observation(EO)data ranges from global solutions on large cloud infrastructures with web-based access to self-hosted implementations.EO data cubes are a leading technology for facilitating big EO data analysis and can be deployed on different spatial scales:local,national,regional,or global.Several EO data cubes with a geographic focus(“local EO data cubes”)have been implemented.However,their alignment with the Digital Earth(DE)vision and the benefits and trade-offs in creating and maintaining them ought to be further examined.We investigate local EO data cubes from five perspectives(science,business and industry,government and policy,education,communities and citizens)and illustrate four examples covering three continents at different geographic scales(Swiss Data Cube,semantic EO data cube for Austria,DE Africa,Virginia Data Cube).A local EO data cube can benefit many stakeholders and players but requires several technical developments.These developments include enabling local EO data cubes based on public,global,and cloud-native EO data streaming and interoperability between local EO data cubes.We argue that blurring the dichotomy between global and local aligns with the DE vision to access the world’s knowledge and explore information about the planet.

Digital Earth in support of global change research

The Digital Earth concept as originally proposed by former US Vice president Al Gore is now well established and widely adopted internationally.Similarly,many researchers world-wide are studying the causes,effects and impacts of Global Change.The authors commence by describing a five-step approach to the development of Digital Earth technologies.This is followed by a detailed account of Digital Earth research and developments in China.The authors then present the research results of Global Change studies carried out in China,based on the Digital Earth approach.These research results are based on a classification of global change regions.This covers the following global change situations:Forest and grassland fires in Northern China,temperate region desertification and dust storms,underground coal fires,deforestation and carbon sequestration,protection and utilisation of wetlands,Avian Influenza and the spread of diseases,Tibet Plateau uplift and sub-tropical monsoon climate region,and sea-level rise.The research results show that the environment does not behave in a way easily understood by the traditional disciplinary approach.Although man is clearly a contributing factor to certain Global Change aspects,such as underground coal fires,desertification,land use changes etc.,many of the aspects of Global Change are naturally occurring phenomena which have been changing over centuries,and will continue to do so,no matter what actions we undertake to reverse these processes.Hence,in their conclusions,the authors propose that the communities involved in Digital Earth modelling and in Global Change research co-operate closer to overcome the limitations inherent in the current‘conventional’scientific approach,where scientists have very much stayed within their respective scientific boundaries.Such an integrated approach will enable us to build the next level of scientific infrastructure required to understand and predict naturally occurring environmental changes,as well as that of coupled humanenvironmental systems.

The role of GIS in Digital Earth education

A growing number of educators worldwide have become convinced that geotechnologies
including geographic information systems(GIS),global positioning systems(GPS),and remote sensing
are key technologies to prepare students to be tomorrow’s decision makers.Grappling with local,regional,and global issues of the 21st century requires people who think spatially and who can use geotechnologies.Some educators teach geotechnologies as a discipline,emphasising skills.Other educators use geotechnologies as a tool to teach content,such as geography,history,environmental studies,Earth Science,biology,mathematics,economics and other disciplines.Issues such as traffic,population growth,urban sprawl,energy,water,crime,human health,biodiversity and sustainable agriculture are growing in complexity,exist at every scale and increasingly affect people’s everyday lives.Each of these issues has a spatial component.Drivers for geotechnology education include educational content standards,constructivism,the school-to-career movement,active learning,citizenship education,authentic practice and assessment,interdisciplinary education,community connections and a sustained,increasing demand for GIS professionals.Digital Earth is an ideal framework for contextualising domains of inquiry.The Digital Earth community can have a significant impact on the growth of geotechnologies in education,and conversely,the growth of geotechnologies in education and society can foster the forward movement of Earth systems concepts.

Digital Earth 2020:towards the vision for the next decade

This position paper is the outcome of a brainstorming workshop organised by the International Society for Digital Earth(ISDE)in Beijing in March 2011.It argues that the vision of Digital Earth(DE)put forward by Vice-President Al Gore 13 years ago needs to be re-evaluated in the light of the many developments in the fields of information technology,data infrastructures and earth observation that have taken place since.The paper identifies the main policy,scientific and societal drivers for the development of DE and illustrates the multi-faceted nature of a new vision of DE grounding it with a few examples of potential applications.Because no single organisation can on its own develop all the aspects of DE,it is essential to develop a series of collaborations at the global level to turn the vision outlined in this paper into reality.

Arithmetic and Fourier transform for the PYXIS multi-resolution digital Earth model

This paper investigates a multi-resolution digital Earth model called PYXIS,which was developed by PYXIS Innovation Inc.The PYXIS hexagonal grids employ an efficient hierarchical labeling scheme for addressing pixels.We provide a recursive definition of the PYXIS grids,a systematic approach to the labeling,an algorithm to add PYXIS labels,and a discussion of the discrete Fourier transform on PYXIS grids.

Big Earth Data:a new challenge and opportunity for Digital Earth’s development

Digital Earth has seen great progress during the last 19 years.When it entered into the era of big data,Digital Earth developed into a new stage,namely one characterized by‘Big Earth Data’,confronting new challenges and opportunities.In this paper we give an overview of the development of Digital Earth by summarizing research achievements and marking the milestones of Digital Earth’s development.Then,the opportunities and challenges that Big Earth Data faces are discussed.As a data-intensive scientific research approach,Big Earth Data provides a new vision and methodology to Earth sciences,and the paper identifies the advantages of Big Earth Data to scientific research,especially in knowledge discovery and global change research.We believe that Big Earth Data will advance and promote the development of Digital Earth.

Digital Earth’s Nervous System for crisis events:real-time Sensor Web Enablement of Volunteered Geographic Information

Digital Earth(DE)is a powerful metaphor for the organisation and access to digital information through a multi-scale three-dimensional representation of the globe.Recent progress gave a concrete body to this vision.However,this body is not yet self-aware:further integration of the temporal and voluntary dimension is needed to better portray the event-based nature of our world.We thus aim to extend DE vision with a Nervous System in order to provide decision makers with improved alerting mechanisms.Practical applications are foreseen for crisis management,where up-to-date situational awareness is needed.While it is traditionally built through trusted sources,citizens can play a complementary role by providing geo-referenced information known as Volunteered Geographic Information(VGI).Although workflows have been implemented to create,validate and distribute VGI datasets for various thematic domains,its exploitation in real time and its integration into existing concepts of DE,such as spatial data infrastructures,still needs to be further addressed.In this paper we suggest to bridge this gap through Sensor Web Enablement for VGI,where VGI sensing becomes a sense of the DE’s Nervous System.We discuss this approach and its applicability in the context of a forest fire scenario.

Evolution and implementation of the Digital Earth vision,technology and society

Digital Earth’s framework can be traced to evolutionary threads with historic foundations that fostered the fertile conceptual and technological incubation.These threads incorporate writings,such as those of the visionary engineering-genius,Buckminster Fuller,in conjunction with an array of space age develop-ments in computers,internet and communications,satellites,and education.In 1998,when Vice President Al Gore articulated the Digital Earth Vision,he portrayed the vision based upon myriad technology factors for the intellectual foundation and sparked a worldwide phenomenon that fortuitously included the Chinese leadership’s recognition and acceptance.The Beijing Declaration is recognised for its role promulgating the International Digital Earth Symposium series to promote better understanding of the impacts of Digital Earth technology and applications on behalf of all humankind.Combinations of industrial,academic,and government organisations have advanced the technological components necessary for implementing the Digital Earth Vision at a prodigious rate.Commercial leaders,such as Google,have accelerated the influence of large segments of society towards components of the Digital Earth Vision.However,challenges still remain regarding requisite collaboration on international stan-dards for metadata,interoperability,and data formats for space and time that will affect Digital Earth implementation scenarios.Functional requirements for the model Digital Earth geobrowser remain to be fully articulated.The current paper presents an overview of the historical components,the key players on the international scene,the catalytic technological advances,and the societal response to the growth of the Digital Earth community.

A digital earth prototype system:DEPS/CAS

Digital Earth is an information expression of the real Earth,and is a new way of understanding the Earth in the twenty-first century.This paper introduces a Digital Earth Prototype System(DEPS)developed at the Chinese Academy of Sciences(CAS)and supported by the Knowledge Innovation Program of the Chinese Academy of Sciences.Discussions are made to the theoretical model and technical framework of the Digital Earth,and its related key technologies on spatial information processing,spatial data warehouse technology,virtual reality technology,high-performance and parallel computing.The DEPS consists of seven sub-systems including the spatial data,metadata,model database,Grid geoscience computing,spatial information database,maps service and virtual reality.Meanwhile,we developed a series of application systems such as the environment monitoring for the Olympic Games 2008 in Beijing,natural disasters evaluation,digital city,digital archeology,Asia regional aerosol and climate change.The DEPS/CAS displayed the application ability and potential of the Digital Earth in three levels:the global,national and regional.

Distributed geospatial information processing: sharing distributed geospatial resources to support Digital Earth

This paper introduces a new concept,distributed geospatial information processing(DGIP),which refers to the process of geospatial information residing on computers geographically dispersed and connected through computer networks,and the contribution of DGIP to Digital Earth(DE).The DGIP plays a critical role in integrating the widely distributed geospatial resources to support the DE envisioned to utilise a wide variety of information.This paper addresses this role from three different aspects:1)sharing Earth data,information,and services through geospatial interoperability supported by standardisation of contents and interfaces;2)sharing computing and software resources through a GeoCyberinfrastructure supported by DGIP middleware;and 3)sharing knowledge within and across domains through ontology and semantic searches.Observing the long-term process for the research and development of an operational DE,we discuss and expect some practical contributions of the DGIP to the DE.

Hexagonal connectivity maps for Digital Earth

Geospatial data are gathered through a variety of different methods.The integration and handling of such datasets within a Digital Earth framework are very important in many aspects of science and engineering.One means of addressing these tasks is to use a Discrete Global Grid System and map points of the Earth’s surface to cells.An indexing mechanism is needed to access the data and handle data queries within these cells.In this paper,we present a general hierarchical indexing mechanism for hexagonal cells resulting from the refinement of triangular spherical polyhedra representing the Earth.In this work,we establish a 2D hexagonal coordinate system and diamond-based hierarchies for hexagonal cells that enables efficient determination of hierarchical relationships for various hexagonal refinements and demonstrate its usefulness in Digital Earth frameworks.

Geoinformatics and digital earth initiatives:a German perspective

This paper discusses the role of Geoinformatics as a new scientific discipline designed for handling of geospatial information.Depending on the scientific background of the people involved in shaping the emerging discipline,emphasis may be placed on different aspects of Geoinformatics.Applications and developments may address geoscientific,spatial planning,or computer science related matters.The scientific field of Geoinformatics encompasses the acquisition and storing of geospatial data,the modelling and presentation of spatial information,geoscientific analyses and spatial planning,and the development of algorithms and geospatial database systems.It is the position of the author that these tools from Geoinformatics are necessary to bridge the gap between Digital Earth models and the real world with its real-world problems(‘connecting through location’).It is,however,crucial that Geoinformatics represents a coherent integrated approach to the acquisition,storage,analysis,modeling,presentation,and dissemination of geo-processes and not a patchwork solution of unconnected fields of activity.Geoinformatics is as such not a part of Geography,Surveying,or Computer Science,but a new self-contained scientific discipline.The current paper highlights international and national trends of the discipline and presents a number of Geoinformatics initiatives.The research and teaching activities of the newly formed Institute for Geoinformatics and Remote Sensing(IGF)at the University of Osnabrueck serve as an example for these initiatives.All these developments have lead to the long overdue formation of a scientific‘Society for Geoinformatics’(German:Gesellschaft fu¨r Geoinformatik-GfGI)in Germany.

GIScience research challenges for realizing discrete global grid systems as a Digital Earth

Increasing data resources are available for documenting and detecting changes in environmental,ecological,and socioeconomic processes.Currently,data are distributed across a wide variety of sources(e.g.data silos)and published in a variety of formats,scales,and semantic representations.A key issue,therefore,in building systems that can realize a vision of earth system monitoring remains data integration.Discrete global grid systems(DGGSs)have emerged as a key technology that can provide a common multi-resolution spatial fabric in support of Digital Earth monitoring.However,DGGSs remain in their infancy with many technical,conceptual,and operational challenges.With renewed interest in DGGS brought on by a recently proposed standard,the demands of big data,and growing needs for monitoring environmental changes across a variety of scales,we seek to highlight current challenges that we see as central to moving the field(s)and technologies of DGGS forward.For each of the identified challenges,we illustrate the issue and provide a potential solution using a reference DGGS implementation.Through articulation of these challenges,we hope to identify a clear research agenda,expand the DGGS research footprint,and provide some ideas for moving forward towards a scaleable Digital Earth vision.Addressing such challenges helps the GIScience research community to achieve the real benefits of DGGS and provides DGGS an opportunity to play a role in the next generation of GIS.

Digital Earth: decadal experiences and some thoughts

The understanding that mankind should reasonably exploit and utilize earth resources and effectively protect the planet on which we live,is now widely accepted.However,effective actions can only be conducted if we better understand and visualize the earth.To meet this need,digital earth science and technology have been put forward and developed.This paper introduces the evolution and development process of digital earth,and presents an overview by reviewing and analyzing the 1999 and 2009 Beijing Declaration on Digital Earth,the scientific and commercial digital earth systems,global and regional digital earth research,and some existing platforms of digital earth science.It also presents some thoughts about digital earth’s future development.

The framework of a geospatial semantic web-based spatial decision support system for Digital Earth

While significant progress has been made to implement the Digital Earth vision,current implementation only makes it easy to integrate and share spatial data from distributed sources and has limited capabilities to integrate data and models for simulating social and physical processes.To achieve effectiveness of decisionmaking using Digital Earth for understanding the Earth and its systems,new infrastructures that provide capabilities of computational simulation are needed.This paper proposed a framework of geospatial semantic web-based interoperable spatial decision support systems(SDSSs)to expand capabilities of the currently implemented infrastructure of Digital Earth.Main technologies applied in the framework such as heterogeneous ontology integration,ontology-based catalog service,and web service composition were introduced.We proposed a partitionrefinement algorithm for ontology matching and integration,and an algorithm for web service discovery and composition.The proposed interoperable SDSS enables decision-makers to reuse and integrate geospatial data and geoprocessing resources from heterogeneous sources across the Internet.Based on the proposed framework,a prototype to assist in protective boundary delimitation for Lunan Stone Forest conservation was implemented to demonstrate how ontology-based web services and the services-oriented architecture can contribute to the development of interoperable SDSSs in support of Digital Earth for decision-making.