SGP/MWR/B1/B4/B5/B6/C1 - software upgrade (version 3.27)

At 00:00 GMT on 7 January version 3.27 of the MWR operating program was installed and made 
operational at the SGP central facility (C1).  No problems were noted over the next few 
days and the boundary facility MWRs (B1, B4, B5, B6) were upgraded at 20:00 GMT on 11 
January.  This version includes a beam width correction I developed as well as providing the 
capability to automatically level the elevation mirror (that is, to automatically detect 
and correct offsets in the elevation angle stepper motor position.)

On 12 January I discovered that the '486-based MWR computers at B1, B4 and B6 were not 
executing the system command to move and rename the data files so that the ARM data system 
could retrieve them.  Reducing the length of the storage arrays in the auto-leveling 
feature from 1000 to 250 resolved the problem.  This results in the auto-leveling being based 
on only 4 hours of clear sky data rather than 16 hours at B5 and C1.  This version of the 
program is 3.28. Version 3.27 (running at B5 and C1) can be installed if and when these 
computers are upgraded to Pentium-class machines.

The improvement in the quality of the tip curves resulting from the auto-leveling has been 
dramatic: differences in the brightness temperatures at 3 airmasses (19.5 and 160.5 
degrees) have been reduced from +/- 5 K to +/- 0.5 K.  The goodness-of-fit coefficient for 
the tip curves has improved from about 0.995 to over 0.998.  In order to take full 
advantage of this improvement to detect and reject cloudy tip curves, the minimum value of the 
goodness-of-fit coefficient for a valid tip curve has been increased from 0.995 to 0.998.

Editor's Note: The SGP.C1 data were reprocessed in 2004 to produce a common DOD for all 
time.  The 1996-1998 data reprocessing included beam width and mirror-leveling corrections, 
but the data prior to that range did not have these corrections applied.

• 31.4 GHz sky brightness temperature(31tbsky)
• 23.8 GHz sky brightness temperature(23tbsky)
• Total water vapor along LOS path(vap)
• Averaged total liquid water along LOS path(liq)

• 31.4 GHz sky signal(31tipsky)
• 23.8 GHz sky signal(23tipsky)

• 31.4 GHz sky signal(31tipsky)
• 23.8 GHz sky signal(23tipsky)

• 31.4 GHz sky signal(31tipsky)
• 23.8 GHz sky signal(23tipsky)

• 31.4 GHz sky signal(31tipsky)
• 23.8 GHz sky signal(23tipsky)

• Mean 23.8 GHz sky brightness temperature(tbsky23)
• Total water vapor along LOS path(vap)
• Mean 31.4 GHz sky brightness temperature(tbsky31)
• Averaged total liquid water along LOS path(liq)

• 31.4 GHz sky brightness temperature(31tbsky)
• 23.8 GHz sky brightness temperature(23tbsky)
• Total water vapor along LOS path(vap)
• Averaged total liquid water along LOS path(liq)

• Averaged total liquid water along LOS path(liq)
• 23.8 GHz sky brightness temperature(23tbsky)
• 31.4 GHz sky brightness temperature(31tbsky)
• Total water vapor along LOS path(vap)

• Total water vapor along LOS path(vap)
• Averaged total liquid water along LOS path(liq)
• Mean 31.4 GHz sky brightness temperature(tbsky31)
• Mean 23.8 GHz sky brightness temperature(tbsky23)

• Averaged total liquid water along LOS path(liq)
• 31.4 GHz sky brightness temperature(31tbsky)
• Total water vapor along LOS path(vap)
• 23.8 GHz sky brightness temperature(23tbsky)