Searching Simulation and Observational Climate Data Using OGC CSW

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Searching Simulation and Observational Climate
Data Using OGC CSW
Data Catalog Interoperability
Kyle HallidayJune 19, 2006UCRL-PRES-222084
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Overview

• Project Overview / Goal
• Obstacles
• General Approach
• Concrete Approach
• Implementation
• Related Future Work

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Project Overview / Goal

• Observational (satellite) Data located in catalog
  at GMU / NASA Ames
• Simulation Data located in catalog at PCMDI
• Goal
• Develop a unified interface for scientists to use
  to browse and search catalogs
• Browse API THREDDS XML
• Search API OGC CSW

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Problem with Searching

• Observational data and Simulation data are
  different
• Observational data is measured by instruments and
  sensors.
• Simulation data is generated by models for a
  given experiment/scenario in a series of runs and
  averaged over some frequency.
• Common Denominator
• Time, Latitude, Longitude
• Conclusion A meaningful search interface must
  know about these differences, either beforehand
  or on-the-fly.

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Many Pegs, No Holes

• Adapter design pattern

Data Catalog
Client Application
Client Application
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Many Pegs, Square Holes

• Adapter design pattern

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Square Pegs, Square Holes

• Adapter design pattern

Data Catalog
Client Application
OGC CSW Adapter
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Abstract Approach
Client Software
Data Catalog
whatOperationsDoYouSupport()
whatDoesYourDataLookLike, searchCatalog
whatDoesYourDataLookLike()
likeThis
buildInterface()
searchCatalog()
searchResults
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Concrete Approach

• OGC CSW exposes the following methods
• GetCapabilities
• retrieve service metadata (which operations are
  supported, description of catalog, contact info,
  etc)
• DescribeRecord
• Learn about the catalogs information model
• GetDomain
• Dynamically retrieve information about the data
  range of a particular parameter

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Concrete Approach

• GetRecords
• Search the catalog, returning search results and
  associated metadata
• GetRecordById
• Search catalog, returning search results that
  match the given ID
• CSW also supports transactional requests, for
  adding, updating, and deleting records

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Implementation Virtual Organization
GMU (Solaris) (laits.gmu.edu) Globus 4.0.1 with
GMU Certs.
NASA SGT (Linux) (arao2.sgt-inc.com) Globus 3.2
with CEOS Certs.
GMU CA center
GMU (Mac) (geobrain.laits.gmu.edu) Globus 4.0.1
with GMU Certs.
NASA (Linux) (former.intl-interfaces.net) Globus
3.0 with CEOS Certs.
CEOS VO
IPG CA center
GMU (Linux) (data.laits.gmu.edu) Globus 4.0.1
with GMU Certs.
ESG CA center
Ames ipg05 (Linux) (ipg05.ipg.nasa.gov) Globus
4.0.1 with IPG Certs.
LLNL esg2 (Linux) (esg2.llnl.gov) Globus 4.0.1
with ESG Certs.
GMU LAITS VO
NASA IPG VO
LLNL ESG VO
Authentication among different VO
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Implementation Adapter at LLNL
GetRecords
GetRecordsResponse
client
ESGQueryService
CSW Plugin
WCS
ESG Metadata Catalog
ESG Publishing Scripts
GMU GCSF
Data publishing
OGC Testbed Data
server
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Related Work CDAT THREDDS/OPeNDAP Browser
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Related Work CDAT THREDDS/OPeNDAP Browser
Tree View generated from THREDDS XML
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Related Work CDAT THREDDS/OPeNDAP Browser
File Metadata drawn from OPeNDAP
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Related Work CDAT THREDDS/OPeNDAP Browser
OPeNDAP server supports HTTP Basic authentication
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Future Work Advanced Search
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Links

• PCMDI
• http//www-pcmdi.llnl.gov
• GMU LAITS
• http//geobrain.laits.gmu.edu/
• NASA Ames
• http//www.nasa.gov/centers/ames/
• IPCC ESG Data Portal
• http//esg.llnl.gov/portal
• IPCC ESG Data Portal THREDDS Base
• http//climate.llnl.gov/dap/ipcc4/?thredds
• IPCC ESG Data Portal OPeNDAP Base
• http//climate.llnl.gov/dap/ipcc4/
• CDAT Documentation
• http//cdat.sf.net
• PyDAP OPeNDAP Server
• http//pydap.org/
• OGC CSW 2.0 Specification
• http//portal.opengeospatial.org/files/?artifact_i
  d5929version2
• ISO19115/ISO19119 Application Profile for CSW 2.0