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Data to Support Ocean-Atmosphere Research NCAR Research Data Archive (RDA), http://www.dss.ucar.edu. Zaihua Ji, NCAR Steven Worley, NCAR Scott Woodruff, NOAA/ESRL Fourth International Ocean-Atmosphere Conference July 4 - 6, 2007, Qingdao, China. Presentation Outline. Introduction Overview
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Data to Support Ocean-Atmosphere ResearchNCAR Research Data Archive (RDA),http://www.dss.ucar.edu Zaihua Ji, NCARSteven Worley, NCARScott Woodruff, NOAA/ESRL Fourth International Ocean-Atmosphere Conference July 4 - 6, 2007, Qingdao, China
Presentation Outline • Introduction • Overview • Focus, Data Relevant to Ocean-atmosphere Research • RDA Data Archive and Management • RDA Data Usage Statistics • Explore Data Archived in RDA • Future Developments • Summary
Introduction Definition, Research Data Archive (RDA) • Dataset collection to support atmospheric and related geosciences research • Hosted by the Computational and Information Systems Laboratory (CISL) at National Center For Atmospheric Research (NCAR) • Built with data curation and stewardship over more than 40 years • Presently maintained by eight people, educated in meteorology and oceanography • Basic Scale metrics • + 500 datasets • + 800K files • + 120 TB
Introduction Why RDA Access is Unrestricted • Our user community is best served if no restrictions exists • Research needs a very large array of data types • Dataset development requires experts - no one can do it all • Many studies require global data - everyone can make a contribution and everyone should benefit. • Data Management alone has significant associated costs (people, storage, servers, etc) • There are near zero funds to purchase data • If service systems are well designed many people can be economically served • Foremost • We know data sharing works well and we want to be a “best practices” example in the international research community • We have had successful data collaborations and exchanges with China • Focused on building and improving ICOADS
Overview - Data Relevant to Ocean-Atmosphere Research Marine observations • International Comprehensive Ocean-Atmosphere Data Set (ICOADS) • Marine surface observations from ships, moored and drifting buoys, and fixed platforms • Very long time series, 1794-2005, over 200 million obs. • Merging and QA/QC of many different datasets • 20 + year collaborative project between NOAA and NCAR, now receiving more international collaboration • More assistance is welcomed • RDA provides two product lines • Observations • Monthly summary statistics in 1x1 and 2x2 lat. lon. boxes • ICOADS is a source for higher level analyzed products, e.g. • SST analyses • Global atmospheric reanalyses
Overview - Data Relevant to Ocean-Atmosphere Research ICOADS • Example of ICOADS and productsSST: Dec 1942ICOADS and two analyses HadISST from UKMO ERSST from NOAA HadISST ERSST
Overview - Data Relevant to Ocean-Atmosphere Research • ICOADS monthly summary statistics • 10 statistics, e.g. median, mean, nobs… • 23 observed and derived parameters • no bias corrections • All source observations are available in a similar way - derive your own statistics
Overview - Data Relevant to Ocean-Atmosphere Research • World Ocean Database (WOD) and World Ocean Atlas (WOA) • Prepared by Ocean Climate Laboratory NODC, Sydney Levitus and collaborators • First edition 1982, now at 2005 • Worlds largest collection WOD • Approximately, 1900 and forward • Ocean profile observations from many international sources • Many types (XBT, CTD, ARGO, bottle stations, etc) • Quality checked and on observed and standard depth levels Profiling float data added WOD01 WOD05
Overview - Data Relevant to Ocean-Atmosphere Research WOA • analyzed data on standard levels, 1 degree resolution • climatology, seasonal, monthly products (T, S, O2, nutrients, etc..) • Some special products • annual heat content • mix-layer depth • high resolution (.25 degree) T and S climatology
Overview - Data Relevant to Ocean-Atmosphere Research Marine Analyses - SST NOAA OptimumInterpolation SST Analysis • 1981- ongoing , weekly, monthly, 1°x 1°, updated monthly • ICOADS, real-time obs., AVHRR sat. blend • (May ‘07 in background) NOAA Extended Reconstructed SST Analysis • 1854 - ongoing, monthly, 2°x 2°, updated monthly • ICOADS and real-time obs. Hadley Centre HadISST • 1850 - ongoing , monthly, 1°x 1°, updated monthly • ICOADS, real-time obs., AVHRR sat. blend for modern period NOAA Optimum Interpolation Daily SST Analysis • 1/4 °x1/4 °, 1985 - ongoing, two products, updated monthly • ICOADS, real-time obs, AVHRR satellite • ICOADS, real-time obs., AVHRR and AMSR satellite
Overview - Data Relevant to Ocean-Atmosphere Research Marine Analyses - Wind • Global QSCAT/NCEP Blended Analysis • Created by Colorado Research Associates • 0.5° x 0.5 °, 4x daily, 1999 - ongoing • Vector wind components, and curl • New versions are prepared when QSCAT algorithms are improved. Currently, a new version is under development. • Many other good sources from Atmospheric Reanalysis datasets • To be presented later
Overview - Data Relevant to Ocean-Atmosphere Research Marine Analyses - Waves • Global and North Atlantic Atlas of Ocean Waves • Created by Sergey Gulev • 2° x 2 ° and 5° x 5° , monthly, 1958 - 1997 • Significant wave height • Derived from ICOADS visual wave observations • ERA-40 • 1.5° x 1.5 °, 4x daily, 1957 - 2002 • 2-D wave spectra are available for 12 directions and 25 frequencies
Overview - Data Relevant to Ocean-Atmosphere Research • Global Objectively Analyzed Air-Sea Fluxes (OAFlux) • Created by Yu and Weller • 1° x 1°, daily and monthly • Latent and sensible flux, 1981-2002, net short and long wave radiation 1983-2002 • Derived from in situ observations, satellite data, and NWP and reanalysis output • Update is planned for 2003 and onward • Ocean-atmosphere heat, momentum and freshwater flux • Created by Josey et al. • 1° x 1°, climatology • Derived from in situ observations and adjusted to match ocean heat transport estimates Marine Analyses - Fluxes
Overview - Data Relevant to Ocean-Atmosphere Research • Sources • Many useful surface products at different resolutions. Too many to cover here • Main dataset title and temporal coverage • NCEP/NCAR Reanalysis, 1948 - ongoing • NCEP/DOE Reanalysis, 1979 - ongoing • ERA-40, 1957-2002 • JRA-25, forthcoming from JMA, 1979 - ongoing • MERRA, forthcoming from NASA, 1979 - ongoing • Important note about ERA-40 • By agreement RDA can distribute only in U.S., and to a few universities in Canada. • Copy outside this domain is prohibited Marine Analyses - Atmospheric Reanalyses
Overview - Data Relevant to Ocean-Atmosphere Research • NCEP Global Ocean Data Assimilation System (GODAS) • 1° x 1°, pentad and monthly, 1980 - ongoing • 1/3 ° resolution ± 10° of equator • 40 vertical levels, parameters (T, S, ocean current, etc) Marine Analyses - Ocean Reanalyses GODAS Annual mix layer depth
Overview - Data Relevant to Ocean-Atmosphere Research • NCEP Global Final Analysis (FNL) • 1° x 1°, 4x daily, 1999 - ongoing • Updated monthly • ECMWF Global Advanced Operational Surface Analysis • 1.125 ° x 1.125°, 4x daily, 1985 - ongoing • Updated bi-annually • TIGGE (THORPEX Interactive Global Grand Ensemble) • Analyses and forecasts from international NWP centers • Now CMA, ECMWF, NCEP, UKMO and JMA; will add 5 more centers • native model resolutions (approx. 1°), 1x to 4x daily, all ensemble members • Parameters; 10m winds, temperatures, surface radiation and fluxes, etc, • Update, near real time, 2-weeks data online NWP Operational Output
RDA Data Archive and Management • RDA Data Archive Components • Creating Dataset Metadata • Populating Datasets with Data • Updating Datasets • Technology of data archiving • Accumulation of data archived in RDA
Archiving Data with State of Art Technology • Hybrid archiving system with Database Management System (DBMS), Database for short, and file management system • Comprehensive archiving utility: gathering data, archiving to MSS and/or online service, recording file metadata, and publishing data filelists • Automated and complete for periodic data updates: downloading, processing/validating, and archiving data • All archiving, web and DBMS utilities are based upon open source software • Both onsite and offsite backup of whole RDA
Data Archived In RDA(MSS: 121.5 TB, Online: 14.9 TB; By 2007-05)
RDA Data Usage Statistics • How data are accessed • What data are accessed • Who uses the RDA data
How Data Are Accessed(Downloaded between 2006-06-01 & 2007-05-31)
Top 10 Datasets Accessed by Most Users(between 2006-06-01 & 2007-05-31)
Top 10 Datasets by Download Volume(between 2006-06-01 & 2007-05-31)
Top 20 Countries/Areas by Most Users(Online data Between 2006-06-01 & 2007-05-31)
Top 10 Datasets by Most Users FromP.R.China, Taiwan & Hong Kong(Online Data Between 2006-06-01 & 2007-05-31)
Monthly Online Users FromP.R.China, Taiwan & Hong Kong(Between 2005-01 & 2007-05)
Monthly Online Data by Users From P.R.China, Taiwan & Hong Kong(Downloaded Between 2005-01 & 2007-05)
Explore Data Archived in RDA • Registration • Identify dataset • Get the data • Online data • MSS Filelist • Subsetting • Questions and special requests
MSS File List … …
Data Subsetting … …
Future Developments • New data search tool based on standardized metadata, GCMD • Browse tool to identify the files needed, based on DB and file metadata queries • Expanded RDA content, e.g. JRA-25, more ocean reanalysis • User feedback and information sharing at the dataset level using web forum technology • More user subsetting and format conversion • More open archiving and access service for NSF projects • Need specific inclusion and management policies • Modernization of web page look and function
Summary • NCAR’s RDA is an open international data resource • We encourage and facilitate data exchanges • We continually build and improved access to the RDA • Modern DB systems are used for management and public data service • Modern data management methods (DB’s and automation) allow: • Systematic growth • Systematic and secure archiving • Accurate usage assessment metrics • We are always open to suggestions for new data resources and service improvements from the users
Thank You Questions? Contact: • http://dss.ucar.edu/index.html • Zaihua Ji, zji@ucar.edu