AAVSO Solar Division
Digital Data Archives at NGDC
Helen E. Coffey
Christine D. Hanchett
Edward H. Erwin
NOAA
National Geophysical Data
Center (NGDC)
Abstract
The American Association of
Variable Star Observers (AAVSO) Solar Division has maintained an active
observing program for many years in the solar-terrestrial physics disciplines.
Both the American sunspot number R(a) and the Sudden Ionospheric Disturbances (SIDs)
are monitored routinely by an AAVSO worldwide network of observers. The data
are compiled at a central point by a dedicated observer who merges all of the
reduced data reports from the worldwide network and quality controls these
records. A copy of these are sent to the National Oceanic and Atmospheric
Administration (NOAA) National Geophysical Data Center (NGDC) in Boulder,
Colorado, who archives and disseminates solar-terrestrial physics datasets. The
NGDC archives for the R(a) reach back to 1946 and provide a valuable
independant measure of the sunspot number. The SID reports from AAVSO begin in
1958 when the HGDC SID archive begins. We review these archives in the context
of the National Space Weather Program.