[Cosmic_announce] Bug found and fixed in COSMIC ionospheric products

[Doug Hunt]

Dear COSMIC connoisseurs:

A bug has been discovered in COSMIC ionPhs and ionPrf files on CDAAC.
For certain satellites and days, ionPhs and ionPrf profiles are scrambled,
showing many abrupt jumps.

This problem occurs for COSMIC satellites which have SNR problems on one
of the POD (Precise Orbit Determination) zenith-mounted antennas.  These
satellites have had the failing antenna turned off and thus have only one
POD antenna for tracking ionospheric occultations.  A bug in CDAAC
software improperly mixed data from duplicate tracks on the single POD
antenna.

A software patch was applied on day 2009.076 to fix this bug in the
real-time COSMIC processing.  We will fix the problem in the
post-processed data and send out a separate announcement when this is
complete.

Thanks to Qian Wu (NCAR HAO) and Woo-Kyoung Lee (HAO and KASI, Korea) for
finding this problem.

Regards,

   Doug Hunt

dhunt at ucar.edu
Software Engineer IV
UCAR - COSMIC, Tel. (303) 497-2611