GIFTS EDU Validation
UW-SSEC/CIMSS AERIbago

Date:  5 Sept 2006 (Tuesday)
Crew:  Best, DeSlover, Olson, Revercomb, Short, Taylor
Author:  DeSlover
http://www.ssec.wisc.edu/gifts/edu

Weather Conditions:

Moderately thin cirrus (see photo).  Clouds seemed to increase in OD as we because the GIFTS/AERI lab comparison around 0140 UTC.

Tasks:

Primary goal today was to setup and configure all AERIbago instruments at SDL site.  Both AERIs are operating nominally.  The zfli.si1 and zfli.si2 files were modified to account for a minor correction to the laser wavelength per BobK's recommendation (the changes were noted in the individual zfli.* files and will take effect when the systems are rebooted).

AERIbago was oriented near the SDL "hangar" (see photo) and aligned such that the AERIbago AERI system points 1.5 degrees away from the SDL hangar (1700-1730 UTC).  The lab AERI and GIFTS are offset by 3 degrees and will be aligned such that each are 1.5 degrees from the center axis of the external turn mirror.  Thus, all three instruments will have a 1.5 degree slant path relative to zenith.  Both AERIs were operating in nominal (7 minute) sample mode.  I'm not sure if the "lab" AERI was networked prior to shutdown, the data was saved to AE060906_out for the outdoor sample mode.  The lab mode did not occur until 060907 and should not be confused with the outdoor AERI intercomparison.  We did not have a sonde for the side-by-side zenith view comparison.

A sonde was launched at 0140 UTC (06 Sep) as both a test to the sonde instrument status and as a validation to the AERI instrument comparison.  The lab AERI was placed in the lab adjacent to the GIFTS and aligned to the external mirror. We had several problems with the lab AERI:  it would not reboot after it was moved into the lab.  The DSP card had to be reseated before it would reboot (and this was done several times before it actually worked).  Also, because the AERI instrument did not come down gracefully when it was moved (it seemed to be unplugged prior to "shut down"), there were some problems talking to the mirror controller when the AERI computer finally came back up.  A reboot of the AERI computer and instrument solved this problem.

GIFTS data collection began at 0143 UTC (06 Sep)

The Vaisala temperature probe was used to record ambient values at the following locations prior to sonde launch:

AERIbago    	T = 25.3 C	Td = 8.6 C  (recorded from roof top near hatch)
lab AERI		T =  23.6 C	Td = 5.3 C  (recorded adjacent to scene aperture)
turn mirror	T =  24.8 C	Td = 8.1 C  (located in front of AERIbago)
sonde		T =  24.9 C 	Td = 8.2 C  (located at rear of AERIbago)

All instruments seem to be working as expected...scratch that...AERI in lab broke again.  This time it went into chkdsk mode and we're waiting to see if the data survived up to the point of the crash.  The system did not freeze, but started chkdsk on its own so we're not really sure what caused this to occur.  Aside from the fact that we had the problems noted above prior to data collection.  TBD tomorrow morning.