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The Dynamic Quick View (DQV) Service offers an innovative, interactive website for rapid visualization of 4-D marine data, utilizing freely available Web GIS tools and integrated with the MERSEA system via OPeNDAP. Users can explore data through a draggable, zoomable map that facilitates animation creation and timeseries plotting. With support for exporting data to Google Earth, the DQV service enhances interoperability with third-party datasets. This service represents a leap forward in environmental data exploration, promising broader applications beyond marine science.
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Dynamic Quick View, interoperability and the future Jon Blower, Keith Haines, Chunlei Liu, Alastair Gemmell Environmental Systems Science Centre University of Reading United Kingdom
Introduction • We have developed an interactive website and map server for data visualization • work originated in UK e-Science programme and National Centre for Ocean Forecasting • Takes advantage of freely-available Web GIS tools • We have integrated our prototype with the MERSEA system (via OPeNDAP) • not yet an approved MERSEA service • We hope to demonstrate the exciting potential of this system and benefits of adherence to open standards • Will be very important in INSPIRE • Potential use is much wider than marine science
Dynamic Quick View (DQV) Service • Gives very fast previews of 4-D data on an interactive website • Reads data from OPeNDAP servers at the MERSEA TEPs • Draggable, zoomable map • Allows the fast creation of animations • Based on a standards-compliant Web Map Service
Selection of depth Select from all the depth levels of the model
Selection of time (range) Select from all the timesteps in the model Selection of a time range leads to an animation
Finding the data value at a point Click on the data layer, data value and precise position is shown Lon: -64.08 Lat: 36.21 Value: 19.27
Timeseries plots If a time range is selected, can create a timeseries plot at a point
Export to Google Earth • DQV website contains link to load currently-visible data into Google Earth • Our WMS outputs in KMZ format • Can then view data alongside other KML datasets • e.g. DAMOCLES • Can view animations of data • No problem with map projections!
Visualize alongside third-party data • Hurricane Katrina, August 2005 • Showing sea surface temperature (UK Met Office) and storm position/intensity (ECMWF) • Winds cause upwelling of cooler subsurface water on right-hand side of the cyclonic storm track
Selection of non-MERSEA datasets also available OSTIA (GHRSST-PP): SST and sea ice high res (1/20°) NSIDC Snow-water equiv. (non-NetCDF) ECMWF System 3 Reanalysis Everything on the website can be exported to Google Earth
The Web Map Service • DQV website is built on a custom-made WMS • backwards-compatible with OGC spec, version 1.3.0 • Optimized for fast, dynamic generation of map images • Enhancements to allow changing of colour scale, generation of timeseries plots, etc • Reads data from CF-NetCDF files or OPeNDAP servers • reading directly from NetCDF is more efficient WMS OPeNDAP NetCDF
Important features of our WMS implementation • Fast generation of images • Handling of four-dimensional data • Handling of data on unusual grids, e.g. NEMO • Dynamic change of colour scale extent • Generation of animations • Export to Google Earth
Current DQV architecture: centralized Background imagery (from NASA etc) NetCDF NetCDF NetCDF TEP 2 TEP 1 TEP 3 OPeNDAP OPeNDAP OPeNDAP WMS Requires minimal setup Single point of failure Relies on fast, reliable OPeNDAP servers DQV website
Possible future DQV architecture: federated Background imagery (from NASA etc) Third-party WMS TEP 1 NetCDF TEP 2 NetCDF TEP 3 NetCDF OPeNDAP WMS OPeNDAP WMS OPeNDAP WMS Requires each TEP to install WMS No single point of failure More efficient DQV website
MERSEA data in third-party clients NASA World Wind Cadcorp SIS Google Earth
In-situ data • Picture left shows comparison of NEMO model and observations for Nov 2004 • Red dots show bad model-obs fits, green dots are good fits • Google Earth allows very efficient browsing of these large datasets • Could do the same for MERSEA systems, e.g. CORIOLIS • Could read obs and model data from different sources and bring together in Google Earth or another client
DQV future enhancements • Display of wind/current fields as vectors • Caching of image tiles for performance increase • Support for more map projections • E.g. polar stereographic • Display of observations on website • Integration with GeoServer, THREDDS • Requires community assistance • …Lots more!
Conclusions • We have demonstrated a dynamic website for exploring MERSEA data quickly and interactively • Based on an OGC Web Map Service • but with important enhancements • other WMS implementations will not support all the features in DQV • Gives interoperability with third-party services • view MERSEA data alongside third-party data • will be important in INSPIRE • Exciting possibilities for the future!
Contact details jdb@mail.nerc-essc.ac.uk To find website: Google for "Godiva2"