=Paper= {{Paper |id=Vol-1536/paper11 |storemode=property |title= Information-computational System for Online Analysis of Georeferenced Climatological Data |pdfUrl=https://ceur-ws.org/Vol-1536/paper11.pdf |volume=Vol-1536 |dblpUrl=https://dblp.org/rec/conf/rcdl/OkladnikovGTS15 }} == Information-computational System for Online Analysis of Georeferenced Climatological Data == https://ceur-ws.org/Vol-1536/paper11.pdf
    Information-computational system for online analysis of
              georeferenced climatological data
© I.G. Okladnikov          © E.P. Gordov             © A.G. Titov            © T.M.Shulgina
         Institute of Monitoring of Climatic and Ecological Systems SB RAS, Tomsk
          Tomsk branch of Institute of Computational Technologies SB RAS, Tomsk
                                Tomsk State University, Tomsk

oig@scert.ru                    gordov@scert.ru                       titov@scert.ru                     stm@scert.ru



                      Abstract                                   actively used in numerous applications including
                                                                 modeling, interpretation and forecast of climatic and
   An Internet accessible information-computational              ecosystem changes for various spatial and temporal
system (ICS) is dedicated to visualization and analysis          scales [9]. Due to inherent heterogeneity of
of geospatial gridded datasets in the area of Earth              environmental datasets as well as their huge size which
system science (local observations, remote sensing and           might constitute up to tens terabytes for a single dataset,
modeling) and climatology in particular. This online             at present, studies in the area of climate and
ICS is based on a dedicated software framework                   environmental change require a special software
consisting of three key parts: server-side computational         support [5]. A dedicated online information-
back-end, server-side middleware represented by                  computational system for analysis of georeferenced
Geoserver software and PHP controllers, and JavaScript           climatological and meteorological data is presented in
library for building typical components of web mapping           this work. It is based on Open Geospatial Consortium
client GUI developed using AJAX techniques. Huge                 (OGC) standards and involves a number of modern
multidimensional geospatial datasets are stored in a             solutions such as object-oriented programming model,
Network Common Data Form (NetCDF) and processed                  modular composition, and JavaScript components based
by a set of validated software modules included in the           on GeoExt library [12], ExtJS Framework [23] and
back-end. Results of a processing are represented by             OpenLayers software [15]. This system is being
overlapped raster and vector layers placed over a                developed in the framework of a big research project
georeferenced       background.      Data     processing         aimed to creation of a distributed hardware and
functionality allows performing basic and complex                software platform for monitoring and forecasting of
statistical analysis of climatological data whilst online        regional climatic and ecological changes and supporting
geo-information system (GIS) instruments give a user             of continuous education. And the work is still not
an ability to combine and place georeferenced results            finished.
over a chosen cartographical basis. It can provide
specialists involved into multidisciplinary research             2 Related work
projects, and even users without programming skills,
with reliable and practical online instruments for                   At present, only few web-based information systems
integrated research of climate and ecosystems changes            devoted to handling of geophysical data are known:
through a unified web-interface.                                 GIOVANNI – GES-DISC (Goddard Earth Sciences
                                                                 Data and Information Services Center) Interactive
1 Introduction                                                   Online Visualization ANd aNalysis Infrastructure ([1],
                                                                 [8]); dissemination system based on Coupled Climate
    Specifics and regional environmental applications of         Model of Institute for Numerical Mathematics of the
basic    Earth     system     sciences   make      them          RAS (INM RAS, [3]); Climate explorer by Royal
multidisciplinary, involving into studies a number of            Netherlands Meteorological Institute (KNMI, [2]);
nationally and internationally distributed research              distributed    informational-analytical    system     for
groups. Success of this cooperative work depends on              searching, processing and analysis of spatial data based
ability of these groups to rapidly exchange data and             on the combination of GIS and Web technologies
knowledge, coordinating activities and optimizing                currently being developed at Institute of Computational
usage of information-computational resources, services           Technologies of the SB RAS (ICT SB RAS, [24]); An
and applications. Georeferenced datasets are currently           Integrated Mapping and Analysis System with
                                                                 Application to Siberia (RIMS, [19], [21]). Nevertheless,
Proceedings of the XVII International Conference                 in spite of presence of some efforts made in Earth and
«Data Analytics and Management in Data Intensive                 Space Sciences Informatics research area there is still a
Domains» (DAMDID/RCDL’2015), Obninsk, Russia,                    lack of powerful online tools combining various
October 13 - 16, 2015




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capabilities to perform online processing, analysis and               To satisfy these requirements the information-
visualization of multidimensional heterogeneous data               computational system was based on a dedicated
collections using unified web interface for integrated             software framework for developing thematic online ICS
study of global and regional environmental changes.                for analysis of dynamics of Earth system components
                                                                   [26]. This software framework includes:
3 Results                                                              1) A server-side computational back-end (core),
                                                                   providing data access and processing, and output of
   Basic requirements to functional capabilities of the            results;
system were defined through meetings with specialists                  2) A server-side middleware including PHP [16]
in the area (climatologists, ecologists and biologists             controllers run by web portal and providing
from Russian and international institutions) and analysis          management of cartographical web services,
of literature ([10], [13], [22]). These requirements also          computational core and components of graphical user
include key features of a typical thematic web GIS:                interface (GUI);
Internet-access by means of a common graphical                         3) A JavaScript library for developing components
Internet-browser to all data processing and visualization          of client web GIS application GUI based on AJAX
tools; abilities to overlay processing results as layers on        techniques.
top of geo-referenced background with basic functions                  Computational backend of the information-
of desktop GIS, such as map navigation, synchronous                computation system is developed using high-level open-
overview of layers at different scales with capability to          source GNU Data Language (GDL, [6]) and Python
show/hide/rearrange them, associating specific colors in           [20]. These are powerful programming languages
a legend with range of values, and inspecting data                 providing reliable computational and visualization
values at specific coordinates of several spatial data             routines, as well as application programming interface
layers at once. To provide interoperability with other             (API) for NetCDF [14] library and PostgreSQL [18]
information systems requirements were expanded to                  database controller. Middleware implementing basic
include support for exporting of results in NetCDF files,          functionality such as user authentication, database
geo-referenced Tagged Image File Format (geoTIFF,                  connectivity, HyperText Markup Language (HTML)
[7]), Open Geospatial Consortium (OGC) Keyhole                     templates usage, language localization, content
Markup Language (KML) and Geography Markup                         management system and so on is represented by a web
Language (GML).                                                    portal      and       an      integrated    set     of




                                           Fig.1. Main window of the system

dedicated PHP modules (controllers). They are                      (WMS/WFS) and geospatial data storage. Client-side
organized into the package structure and provide server-           part of the ICS is developed using framework GeoExt,
side API to interact with graphical user interface,                ExtJS and OpenLayers JavaScript libraries. It provides
computational backend, cartographical web services                 AJAX-based client-side API for implementation of




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corresponding PHP controllers as well as basic GUI                     Spatially distributed results of a processing are
elements of typical desktop application.                           represented by shaded color plots stored in geoTIFF
     Several geophysical datasets are available for                files. Spatially distributed results in the form of contour
processing by the system: NCEP/NCAR Reanalysis II,                 plots, vector wind streams and local point observations
JMA/CRIEPI JRA-25 Reanalysis, ECMWF ERA-40                         are stored in ESRI Shapefiles [4]. 2-D plots and
Reanalysis, ECMWF ERA Interim Reanalysis,                          diagrams are stored in Encapsulated PostScript (EPS)
MRI/JMA APHRODITE’s Water Resources Project                        format files. Additionally, files with raw values (CSV,
Reanalysis, DWD Global Precipitation Climatology                   XML, NetCDF) could be written to accompany
Centre’s data, GMAO Modern Era-Retrospective                       GeoTIFF and EPS files.
analysis for Research and Applications, reanalysis of                  The main advantage of the system is that it gives
Monitoring atmospheric composition and climate                     users an ability to perform mathematical and statistical
(MACC)        Collaborated      Project,   NOAA-CIRES              data analysis of huge georeferenced datasets without
Twentieth Century Global Reanalysis Version II, NCEP               downloading them, remotely through a window of a
Climate Forecast System Reanalysis (CFSR),                         web browser installed on a common desktop computer
meteorological observational data for the territory of the         connected to Internet [27]. In contrast to many scientific
former USSR for the 20th century, results of modeling              gateways and analytical web-systems existing
by global and regional climatological models, and this             nowadays (http://sciencegateways.org/), this system
list is extending. Flexibility of the system allows easy           allows not only to do remote data analysis and
and fast expansion of number of datasets available for             visualization, but to represent results in a web interface
processing and visualization.                                      as a stack of georeferenced layers on an interactive map
     Reanalyses and modeling data are stored as NetCDF             implementing GIS features (Fig. 1 and 2), and to export
files organized in a hierarchy of a file system’s                  them as OGC-compliant (in terms of metadata) layers
directories:                                                       using web mapping (WMS) and web feature (WFS)
//                                            services, thanks to a tight fusion of web-, GIS- and
      /                                              cloud-computing technologies. At present, for the Earth
           /                                   system science area there is no similar information-