[Personnel: Last_Name='ERWIN', Middle_Name='H.', First_Name='EDWARD']
Solar IrradianceEntry ID: gov.noaa.ngdc.G00547
Abstract: ABSTRACT: The "solar constant" is, in fact, not constant. Recent satellite observations have found that the Total Solar Irradiance (TSI), the amount of solar radiation received at the top of the Earth's atmosphere, does vary - see the graph for the results from six satellites(ftp://ftp.ngdc.noaa.gov/STP/SOLAR_DATA/SOLAR_IRRADIANCE/IRRAD97.PDF). "The variations on solar rotational and active region ... time scales are clearly seen. The large, short-term decreases are caused by the TSI blocking effect of sunspots in magnetically active regions as they rotate through our view from Earth. The peaks of TSI preceding and following these sunpot "dips" are caused by the faculae of solar active regions whose larger areal extent causes them to be seen first as the region rotates onto our side of the sun and last as they rotate over the opposite solar limb." [Excerpted from the UARS descriptive text] The TSI provides the energy that determines the Earth's climate.Variations of the total solar irradiance (solar constant) have become an important new tool for studying the sun since the deployment of a new generation of precise solar flight instrumentation, such as the ACRIM I satellite experiment on the Solar Maximum Mission (SMM) in 1980. The study of variations of the spectral irradiance observed in the EUV also has developed rapidly. The largest variations of the total irradiance occur on time scales of a day to several weeks and are caused by solar active regions. Efforts to model the radiative effects of active regions are proceeding and the first round of results from these have appeared in literature. Disagreements have quickly surfaced in this new field and a topical workshop was convened at the California Institute of Technology in June 1983, to provide both formal and informal opportunities for dialog between those actively working in this area. The papers resulting from this workshop are collected in the report by LaBonte et al. (1984). NGDC Boulder holds the SMM satellite irradiance data for February 1980 to May 1989 and the Nimbus data for November 1978 to the present. Also available are the Hoyt and Eddy model data for the period 1974 to 1981. Early data by Abbott, Smithsonian Institution, from many locations worldwide covering the period 1902 to 1962 are available also.
SUPPLEMENTAL INFORMATION: This archive contains data from:Composite Total Solar Irradiance database 1978-present, compiled by C. Frohlich and J. LeanACRIM Composite TSI Time Series 1978-present, compiled by R. WillsonSORCE (Solar Radiation and Climate Experiment) 2003 - present, compiled by G. RottmanTotal Solar Irradiance (TSI) data from individual satellites: ERBS (Oct 1984-Aug 2003), NIMBUS (Nov 16, 1978-Dec 13, 1993), NOAA9 (Jan 23, 1985-Dec 20, 1989), NOAA10 (Oct 22, 1986-Apr 1, 1987), SMM Feb 16, 1980-June 1, 1989), SOHO VIRGO (Jan 18, 1996-Nov 13, 1999) and UARS (Oct 4, 1991-Dec 31, 1997)Older, archival databases contain data from:Dr. John Arvesen's Solar Spectral Irradiance data at the top of the atmosphere in the 300-2500 nm wavelength range (UV to visible), from NASA research aircraft -- 11 flightsCharles Greeley Abbot solar constant database -- Note: 2 years of scientific investigation are needed to bring this database into a scientifically useable research database
CURRENTNESS REFERENCE: Ground Condition
Purpose: PURPOSE: To provide long-term scientific data stewardship for the Nation's geophysical data, ensuring quality, integrity, and accessibility.
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Data Set Citation
Dataset Originator/Creator: Please See Summary
Dataset Title: Solar Irradiance
Dataset Series Name: Solar Geophysical Data (SGD) International Standard Serial Numbers (ISSN)
Dataset Release Date: 1984
Dataset Release Place: Boulder, CO
Dataset Publisher: National Geophysical Data Center
Issue Identification: 'ISSN 0038-0911 Solar Geophysical Data (SGD)'
Other Citation Details: http://www.ngdc.noaa.gov/stp/SOLAR/ftpsolarirradiance.htmlOnline Resource: ftp://ftp.ngdc.noaa.gov/STP/SOLAR_DATA/SOLAR_IRRADIANCE
Start Date: 1978-08-01
ISO Topic Category
Access Constraints ACCESS CONSTRAINTS: No Constraints
DISTRIBUTION LIABILITY: While every effort has been made to ensure that these data are accurate and reliable within the limits of the current state of the art, NOAA cannot assume liability for any damages caused by any errors or omissions in the data, nor as a result of the failure of the data to function on a particular system. NOAA makes no warranty, expressed or implied, nor does the fact of distribution constitute such a warranty.
Use Constraints None
Data Set Progress
Distribution Size: 55.0
Distribution Format: ASCII
Fees: Free downloadable data Depends on amount of data requested.
Role: TECHNICAL CONTACT
Role: DIF AUTHOR
Phone: (303) 497-6133
Fax: (303) 497-6513
Email: Edward.H.Erwin at noaa.gov
NOAA/NESDIS/NGDC E/GC2 325 Broadway
Province or State: CO
Postal Code: 80303
Creation and Review Dates
DIF Creation Date: 2009-06-15
Last DIF Revision Date: 2011-03-02