Time coverage of the data

The following table provides an overview of the data sets of SACS, with the time period covered by the data sets, as well as the data sets planned for use in the (near) future, listed per satellite instrument. The date between brackets in the off-line data archive column is the date of the first available data.

instrument     data products	near-real-time processing		off-line data archive [start = first data day]
	nrt data archive	operational
SCIAMACHY     SO2 column     Aerosol index	Jan 2004 - Apr 2012 Jan 2009 - Apr 2012	Sep 2006 Jul 2010	Jan 2004 - Apr 2012 Jan 2009 - Apr 2012 [start:  02 Aug. 2002]
OMI     SO2 column     Aerosol index	Aug 2004 - May 2025 Jul 2009 - May 2025	Jul 2009 Jul 2009	Aug 2004 - May 2025 Jul 2009 - May 2025 [start:  17 Aug. 2004]
GOME-2     SO2 column     Aerosol index	Jan 2007 - May 2025 Jun 2010 - May 2025	Feb 2008 Jun 2010	Jan 2007 - May 2025 Jun 2010 - May 2025 [start:  04 Jan. 2007]
IASI     SO2 dbt     Aerosol/Ash flag	Oct 2007 - May 2025 Oct 2007 - May 2025	Aug 2010         --	Oct 2007 - May 2025 Oct 2007 - May 2025 [start: 2007]
AIRS     SO2 dbt     Aerosol/Ash flag	Sep 2002 - May 2025 Sep 2002 - May 2025	Sep 2010         --	Sep 2002 - May 2025 Sep 2002 - May 2025 [start: 2007]

Remarks: an entry "--" means that that data set is not yet available

 

  Missing data in the SO2 off-line data archive

The satellites carrying the instruments perform 14 or 15 orbits per day. It happens that for one or
more of these orbits data is missing, either because the instrument did not measure anything, or
because the measurement is of too low quality for a reliable retrieval. This missing data leads to
gaps in the plots of the daily data. For some geographic regions the web pages accessing the
data archive will then show empty pictures.

There are also days with no data at all, again because of lack of measurements of lack of
the quality of these measurements. For these days there will be no data in the archive at all,
and the web pages accessing the data archive will show a message.

The following tables lists whole days without any SO₂ and AAI data in the off-line data archive,
i.e. for which no maps are shown. The first day for which off-line archive data is available is given above.
Note that this table is maintained by hand and may thus be incomplete.

Year	SCIAMACHY		OMI		GOME-2		IASI
	Month	Days	Month	Days	Month	Days	Month	Days
2010	March Feb. Jan.	04 01-02 29-31	May Jan.	02 19	[none]	[none]	--	--
2009	Aug. June April March Jan.	10 04,16 07,08 31 01-03	Aug.	05	Dec. Nov. Sep. April.	13-15 29 08-10 06-08 17-19	--	--
2008	Dec.	19-31	[n/a]	[n/a]	Nov. Sep. Aug. Feb. Jan.	29 08-11 15 17 28	--	--
2007	Dec. Sep.	02-04 25-27	[n/a]	[n/a]	Sep. April March Jan.	19 09, 21-25 03-05 01-03	--	--
2006	Dec. Nov. Sep. May April Jan.	13-15 29 08-10 26 06-08, 17-19 14	[n/a]	[n/a]	[n/a]	[n/a]	[n/a]	[n/a]
2005	May Jan.	12 01-02	[n/a]	[n/a]	[n/a]	[n/a]	[n/a]	[n/a]
2004	Dec. Nov. Oct. Sep. June May Jan.	20-31 17 01 23 18-28 09 01-03	[n/a]	[n/a]	[n/a]	[n/a]	[n/a]	[n/a]