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Geomagnetic Storm Sudden Commencements

Metadata Updated: November 12, 2020

Storm Sudden Commencements (ssc) 1868 to present: STORM1 and STORM2 Lists: (Some text here is taken from the International Association of Geomagnetism and Aeronomy (IAGA) Bulletin 39) 1868-1967 data (STORM1.SSC) are from IAGA Bulletin 33. These data are based on 3 observatories. Only one of them was at low latitude; the other two, with an invariant magnetic latitude of 50 degrees, were strongly sensitive to the auroral effect. 1968-1975 data (STORM2.SSC) are from IAGA Bulletin 39. These data are much more reliable. The monthly reports from all observatories guarantee that very few events are omitted. With the examination of five low-latitude records, the changes of rhythm could be evaluated much better, and events were kept of rejected on a more rational basis. However, it is probable that, for statistical use, both lists will be relatively homogeneous. Indeed, Alibag was the low-latitude observatory of the 100-year list and belongs, in the 1968-1975 list, to the group form which the amplitudes are close to the average of five observatories. 1976-1982 data are from IAGA Bulletin 32 series. These data are reduced in the same manner as the 1968-1975 data. 1983-present data are from the monthly ISGI Bulletins (DeBilt, Netherlands - 1983-1987 data; Institut de Physique du Globe, Paris, France - 1988-present data.

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License: No license information was provided. If this work was prepared by an officer or employee of the United States government as part of that person's official duties it is considered a U.S. Government Work.

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Metadata Date September 18, 2015
Metadata Created Date November 12, 2020
Metadata Updated Date November 12, 2020
Reference Date(s) May 13, 1998 (publication)
Frequency Of Update monthly

Metadata Source

Harvested from NGDC STP Geomag

Additional Metadata

Resource Type Dataset
Metadata Date September 18, 2015
Metadata Created Date November 12, 2020
Metadata Updated Date November 12, 2020
Reference Date(s) May 13, 1998 (publication)
Responsible Party Unknown
Contact Email
Guid gov.noaa.ngdc.stp.geomag:G01184
Access Constraints Use Constraints: None, Access Constraints: No Constraints
Bbox East Long 180.000000
Bbox North Lat 90.000000
Bbox South Lat -90.000000
Bbox West Long -180.000000
Coupled Resource
Frequency Of Update monthly
Harvest Object Id 1d50b844-58b7-40d7-a168-9bd7f6d5f094
Harvest Source Id a34cf322-93d8-4d56-8060-2a5c299d068f
Harvest Source Title NGDC STP Geomag
Licence 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.
Metadata Language eng; USA
Metadata Type geospatial
Progress underDevelopment
Spatial Data Service Type
Spatial Reference System
Spatial Harvester True
Temporal Extent Begin 1968-01-01

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