SGP/SIRS - 990430

Data quality for this site is good this month: 100% of the daytime data are present, and 
89.8% of the present daytime data earn passing or low-level flags. Another 8.8% of the 
present daytime data are assigned strange-but-true flags. Low-level flags seen early on 
clear or partly cloudy mornings indicate that the DS is too low or the DD or NIP too high by 
the three-component test. Overcast conditions force the DS and DD below twilight or 
daytime empirical limits on a number of occasions, and the NIP repeatedly falls below daytime 
empirical limits on the afternoon of the 13th. On the afternoon of the 14th the 10m tower 
was removed for upgrade, so the US and UIR signals read 99999: missing data. On the 
morning of the 22nd the suntracker failed, but was returned to proper operation that same 
morning. No other problems noted.

• Battery voltage(vBatt)
• base time in epoch(base_time)
• Downwelling Shortwave Hemispheric Irradiance, Ventilated Pyrgeometer, Standard
  Deviation(down_short_hemisp_std)
• Downwelling Shortwave Diffuse Hemispheric Irradiance, Pyrgeometer, Minima(down_short_diffuse_hemisp_min)
• Downwelling shortwave hemispheric irradiance, pyranometer, maxima(down_short_hemisp_max)
• Downwelling longwave hemispheric irradiance, pyrgeometer(down_long_hemisp)
• Upwelling (10 meter) Shortwave Hemispheric Irradiance, Ventilated Pyranometer,
  Standard Deviation(up_short_hemisp_std)
• Shortwave direct normal irradiance, pyrheliometer(short_direct_normal)
• Shortwave direct normal irradiance, pyrheliometer, minima(short_direct_normal_min)
• Upwelling (10 meter) Shortwave Hemispheric Irradiance, Pyranometer, Maxima(up_short_hemisp_max)
• Upwelling Longwave Hemispheric Irradiance, Pyrgeometer, Minima(up_long_hemisp_min)
• Down-welling unshaded pyranometer voltage(down_short_hemisp)
• Time offset from base_time(time_offset)
• lon(lon)
• Downwelling Shortwave Diffuse Hemispheric Irradiance, Ventilated Pyranometer(down_short_diffuse_hemisp)
• Shortwave Direct Normal Irradiance, Pyrheliometer, Maxima(short_direct_normal_max)
• Shortwave Direct Normal Irradiance, Pyrgeometer, Standard Deviation(short_direct_normal_std)
• Upwelling (10 meter) Longwave Hemispheric Irradiance, Ventilated Pyrgeometer,
  Standard Deviation(up_long_hemisp_std)
• North Latitude(lat)
• Downwelling Longwave Hemispheric Irradiance, Pyrgeometer, Maxima(down_long_hemisp_max)
• Downwelling Longwave Hemispheric Irradiance, Ventilated Pyrgeometer, Standard
  Deviation(down_long_hemisp_std)
• 25 meter Upwelling Shortwave Hemispheric Irradiance, Pyranometer(up_short_hemisp)
• Upwelling longwave hemispheric irradiance, pyrgeometer, maxima(up_long_hemisp_max)
• -180.0 - +180.0(alt)
• Downwelling Shortwave Hemispheric Irradiance, Pyranometer, Minima(down_short_hemisp_min)
• Downwelling shortwave diffuse hemispheric irradiance, pyranometer, maxima(down_short_diffuse_hemisp_max)
• 10 meter Upwelling Longwave Hemispheric Irradiance, Pyrgeometer(up_long_hemisp)
• Downwelling Shortwave Diffuse Hemispheric Irradiance, Pyranometer, Standard
  Deviation(down_short_diffuse_hemisp_std)
• Upwelling shortwave hemispheric irradiance, pyranometer, minima(up_short_hemisp_min)
• Downwelling Longwave Hemispheric Irradiance, Pyrgeometer, Minima(down_long_hemisp_min)

• 10 meter Upwelling Longwave Hemispheric Irradiance, Pyrgeometer(up_long_hemisp)
• -180.0 - +180.0(alt)
• North Latitude(lat)
• Time offset from base_time(time_offset)
• Direct-beam normal solar irradiance(nip)
• Down-welling pyrgeometer dome thermistor resistance(down_long_dome_resist)
• Downwelling longwave hemispheric irradiance, pyrgeometer(down_long_hemisp)
• lon(lon)
• Down-welling pyrgeometer case thermistor resistance(down_long_case_resist)
• base time in epoch(base_time)
• Up-welling pyrgeometer dome thermistor resistance(up_long_dome_resist)
• 25 meter Upwelling Shortwave Hemispheric Irradiance, Pyranometer(up_short_hemisp)
• Down-welling unshaded pyranometer voltage(down_short_hemisp)
• Up-welling pyrgeometer case thermistor resistance(up_long_case_resist)
• Shaded pyranometer voltage(short_diffuse)