Spatial Data Access Tool: Yaxing Wei, Suresh-Kumar Santhana-Vannan, Robert B. Cook, Bruce E. Wilson, and Tammy W. Beaty Oak Ridge National Laboratory December 14 th 2009 Enable visualization and access of geospatial data using OGC services and Google Earth

2 ORNL DAAC Oak Ridge National Laboratory Distributed Active Archive Center (ORNL DAAC) –NASA-sponsored source for biogeochemical and ecological data and models useful in environmental research Data in ORNL DAAC –field campaign, land validation, regional and global data –over 800 data sets, ~220,000 files, ~1.1TB size –various formats

3 MAST-DC The Modeling and Synthesis Thematic Data Center (MAST-DC) –provide data management support for North American Carbon Program (NACP) project –provide data to users in the formats, resolutions, and projections based on their requirements Data in MAST-DC –model inputs, model outputs, observations (forest/crop, tower flux), and other related data

4 Challenges faced by data centers Rapidly increasing archiving rate Heterogeneity of geospatial data Rapidly growing user community and user requirements Heterogeneity of data delivering mechanism –Diverse ways in which data centers publish and deliver geospatial data introduce extra burden to users to access data from multiple data centers

5 New solutions needed! Data users need to: –Find and visualize data efficiently –Access diverse data in ready-for-use formats –Access diverse data in a standard way ORNL DAAC and MAST-DC have tapped into the benefits offered by Open Geospatial Consortium (OGC) standards, Web-enabled GIS tools, and Virtual Globe technology.

6 OGC and its Standards Open Geospatial Consortium (OGC) –non-profit, international, voluntary consensus standards organization that is leading the development of standards for geospatial and location based services. OGC Web Coverage Service (WCS) –Web service for actual geospatial coverage data access OGC Web Map Service (WMS) –Web service for geospatial data (coverage or feature) visualization Goal: interoperability

7 The ORNL WCS and WMS Servers MapServer-based WCS – –Version –Customized geospatial coverage access Spatial/temporal/band subsetting Reprojection/resampling Reformatting: GeoTIFF, Arc/Info ASCII Grid, netCDF, NITF, and ERDAS Imagine WMS – –Version –Customized geospatial data visualization Automatic/manual-defined color scheme Spatial/temporal/band subsetting Reprojection/resampling Popular image formats: PNG, JPEG, and GIF

8 Spatial Data Access Tool (SDAT) OGC standards-based Web application for geospatial data visualization and download Web-based GUI brings the benefits of ORNL WCS/WMS servers to end users –interactive map widget – driven by WMS –customized data download – driven by WCS Two levels of data organization –Data set –Data file (granule)

9 65 Data Sets in SDAT Land Cover – 6 –MODIS, AVHRR, GLC2000, NLCD 2001, etc. Elevation – 2 –GTOPO30, SRTM Soil – 4 Climate – 5 –Koppen-Geiger climate classification Ecoregion – 1 Carbon cycling model outputs – 30 –ORCHIDEE, SiB3, CLM-CASA, etc.

10 SDAT User Interface – Set Level Browse data sets/files Link to detailed metadata in data set level data set list data file (granule) list

11 SDAT User Interface – File Level file-level metadata projection definition in OGC WKT format OpenLayers-based interactive map widget On the fly map reprojection WCS-based data access options

12 Virtual Globe technology World-Wide Web –SDAT is Web-based Web-Wide World –Emerging “virtual globe” technology, like Google Earth, brings a new platform and many more benefits for geospatial data visualization and delivery Local Computer World-Wide Web (SDAT) Web-Wide World (Google Earth)

13 Google Earth KMZ A KMZ file for each data set is provided for users to visualize data in Google Earth –thanks to Karl Benedict and Renzo Sanchez-Silva for the ESIP-EDAC WMS to KML converter WMS-based dynamic maps generation WMS-based dynamic legend images generation

14 Benefits (1) Rich and valuable background maps (high resolution satellite images, roads, landmarks, borders, etc.)

15 Benefits (2) Powerful address/keywords-based locating capability –what if the user want to see a data near Yosemite?

16 Benefits (3) Excellent data visualization capability Google Earth wraps National Land Cover Data (NLCD 2001) to terrain –globe-based –arbitrary angle of view –fly –3-D –terrain

17 Benefits (4) Overlay any map from any data set –Land cover change in Three Gorges Dam area MODIS Land Cover (IGBP) in 2001MODIS Land Cover (IGBP) in 2007 What we see Increase of water area Reduce of croplands Woody Savannas replaced by Mixed Forests What we think Impact on environment residency relocation more …

18 Benefits (5) Time-series animation –Monthly CO2 flux for the period 1998 – 2006 at 1 degree spatial resolution (simulated by SiB3 model)

19 Benefits (6) Embed SDAT tool within Google Earth –support of Javascript and iframe since version 5

20 Summary and future work ORNL DAAC and MAST-DC are rich sources for biogeochemical and ecological data useful in environmental research. The ORNL OGC servers and SDAT provide efficient and customizable visualization and access to geospatial data in a standard way Google Earth serves as a new platform and brings many more benefits for geospatial data visualization and delivery Incorporate more OGC standards, such as WFS

21 Thank you!

22 Client Software Role of SDAT SDAT OGC Servers (WCS/WMS/…) Metadata Catalog (Mercury) Data Order System User Metadata Archive Data Center (ORNL DAAC, MAST-DC,..) Data Archive