Satellite & Model Product Evaluation Center (SPEC): A Software System Providing Ready Access To Co-located Data Subsets

From Satellite, In-situ, and Model Sources1Robert B. Cook, Jerry Pan, Suresh K. SanthanaVannan, Bruce E. Wilson, Yaxing Wei

2Huai-min Zhang, Steve Ansari, Stephen Del Greco, Jeff Privette, Michael Urzen, Lou Vasquez

1 ORNL DAAC, Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6407, 2 National Climatic Data Center (NCDC), NOAA, Asheville, NC 28801-5001

NASA MODIS /VIIRS Science Team Meeting, January 26-28, Washington, DC

IntroductionSatellite imagery provides a means of extending our understanding of land surface properties from site-specific studies to larger regions. Model (re)analysis also enhances our understanding of the physical processes that affect human life. In addition, site-based in-situ data products can serve to evaluate remote sensing data products as well as model predictions. However, acquiring, preparing, and analyzing time-series of remote sensing products or model output along with site-based data can be computationally challenging.

NASA’s ORNL DAAC and NCDC are collaborating to develop a Web-based system that access co-located data subsets from field observations, model output, and remote sensing records. The system is aimed to support quantitative calibration, validation and algorithm and model improvement.

ACKNOWLEDGEMENTS: This study was supported by the NASA’s Earth Observing System Data and Information System. ORNL is managed by the University of Tennessee-Battelle LLC under contract DE-AC05-00OR22725 with the U.S. Department of Energy.

Status

• Server-side coding on subset preparation and loading into database near completion.

• Continue to cache co-located subsets into database.• Developing use cases for client-side modules, seeking input on requirements.• Beta prototype desktop client with command line tool available by Summer

2010.

Summary of the SPEC System

• Reusable, generic, and modular system.• Designed to acquire subsets of spatial data (remote sensing images, model

output, map layers).• Facilitates the simultaneous access and intercomparison of in situ, satellite,

and model output data.• Used to evaluate satellite products as well as model results.

Key Benefits Provide a uniform approach (Common Data Model-based) for the extraction of

grid/swath from point, line, polygon and trajectory data, and theregy maximize reusability

Provide a large, high-performance cache of satellite/model data for select locations.

Provide a desktop or command-line tool for: Co-locations/matchups of your data. Integration of your data with the SPEC database cache. Statistical analysis and export to common formats. Monitoring and automated alerts.

Bondville, IL AmeriFlux Site Cropland

Examples of in situ observation networks: Climate Reference Network (CRN) sites — continuous

high quality NOAA climate data , including air and surface temperature, rainfall, and radiation.

AmeriFlux sites – Continuous observations of ecosystem level exchanges of CO2, water, and energy flux across North America.

Example Output from Pilot Application (http://daacds.ornl.gov:8080/spec/)

Contacts: Jerry Pan (pany@ornl.gov) or Steve Ansari (steve.ansari@noaa.gov)

NetCDF HDF

Data Extractor(NetCDF for Java)

Grid | Swath

XML Config. File(Colocation points, variables, search

radius, etc..)

GRIB OPeNDAP

GINI

XML Colocation File

Database

Archive

Web Services(URL-based / REST

/ ERDDAP)

Visualization and Data Download

Web Pages or Desktop App.

NcML

THREDDS / OPeNDAP

???

Batch ProcessingProcedures

Architecture Approach Using Common Data Model (grid, swath), extract overlaying pixels (and

neighborhood of pixels) from a specific lat/lon location. Save co-location file as XML.

Load extracted data into Relational Database for fast access. Build Web services for access of data from Web page or client-side tools.

NetCDF HDF

GRIB OPeNDAP

GINI

Data Extractor(NetCDF for Java)

Grid | Swath

XML Colocation File

LocalDatabase

Web Services(URL-based / REST / ERDDAP)

Integration EngineDesktop / Command-Line Application

NcML

Local Files

SPECDatabase(s)

Cached LocationsAny Location

Client Application(GUI and Command-Line)

Server / Client share common modules and communicate via Web Services

ClientServer

Bondville, IL CRN Site Mown lawn

SPEC reads satellite (or any gridded or swath) data and extracts pixel values at site locations. The pixel containing the site and nearby pixels are included and the collocation extent is configurable as part of the data extraction process

Target data sources:

Satellite – VIIRS, MODIS, GOESModel - PCMDIField - AmeriFlux, CRNOther - SURFRAD, ARM…

Pilot Application Select a site from a list,

preview location using Google Map.

Choose variable and data source.

Select the time period of interest.

Submit for online time-series visualization or download subsets.Bondville, IL

CRN Site Cropland

Step 1: Select a Site

Step 2: Select Data Products for Comparison

Step 3: Visualize and Download Data