NOAA-9 SBUV/2 Solar Spectral Irradiance Data                February 13, 2007
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This file briefly summarizes the NOAA-9 SBUV/2 solar spectral irradiance data 
product.  The SBUV/2 instrument measured solar irradiance on an approximately 
daily basis with 1.1 nm resolution.  The data provided here are daily average 
solar spectra over the wavelength range 170-400 nm in 1 nm bins, covering the 
time period March 14, 1985 to May 5, 1997.  The data have been fully 
corrected for long-term instrument calibration changes.  A complete description 
of the data processing procedure can be found in DeLand et al. [J. Geophys. 
Res., 109, D06304, doi:10.1029/2003JD004074, 2004], and on this web site as 
'n09_irrad_jgr_2004.pdf'.  The NOAA-9 SBUV/2 irradiance data are intended for 
use in studies of short-term and long-term solar UV variability.  The estimated
long-term accuracy of the data is 2.3% (2 sigma) at 205 nm, and 1.8% at 250 nm.

Two binary data files and two IDL programs to examine the data are provided.  
'n09_dates_daily.unf' contains the date (year, day of year, running day number 
from 1 January 1985) for every available spectrum.  'n09_spec_daily.unf' 
contains the corresponding spectra (170-400 nm, 1 nm bins, units of 
mW/m^2/nm).  The program 'n09_spec_public.pro' will plot any available NOAA-9
SBUV/2 irradiance spectrum.  'n09_time_public.pro' plots a time series of 
irradiance data averaged over a selected wavelength band.  For a better view of
the data gaps caused by satellite orbit drift, the user may prefer 
'n09_time_public_gap.pro' and its associated subroutine 'plot_data_gap.pro'.
If ASCII files are more convenient, please use 'n09_dates.dat' (year, day of 
year, running day number) and 'n09_irrad.dat' (10 column x 23 row irradiance 
data block for each spectrum).

Solar UV spectral irradiance data from two other SBUV and SBUV/2 instruments are
also available.  Data from Nimbus-7 SBUV covering the period November 1978 to 
October 1986 are available in the binary data files 'n07_dates_daily.unf' and 
'n07_spec_daily.unf', or in the ASCII files 'n07_dates.dat' and 
'n07_irrad.dat'.  Data from NOAA-11 SBUV/2 covering the period December 1988 to 
October 1994 are available in the binary data files 'n11_dates_daily.unf' and 
'n11_spec_daily.unf', or in the ASCII files 'n11_dates_v1.dat' and 
'n11_irrad_v1.dat'.  The format of these files is identical to the 
corresponding NOAA-9 SBUV/2 data files.  

Further information about the long-term characterization of these data sets 
can be found in the following papers:
*  Cebula et al. [JGR, 103, 16,235-16,249, 1998];  NOAA-11 part 1
*  DeLand and Cebula [JGR, 103, 16,251-16,273, 1998];  NOAA-11 part 2
*  DeLand and Cebula [JGR, 106, 21,569-21,583, 2001];  Nimbus-7


Contact Information
===================
Matthew DeLand
Science Systems and Applications, Inc. (SSAI)
10210 Greenbelt Rd., Suite 600
Lanham, MD  20706
Ph. (301) 867-2164
E-Mail:  matthew_deland@ssaihq.com
Web:  http://ventus.gsfc.nasa.gov/solar.html
DATA:  http://ozone.sesda.com/solar/