Unshaded PSP dirty domes

Subject: Unshaded PSP dirty domes

Platform/Measurement: sgpsiros/unshaded PSP

What location was the data collected at: E8, E11                                

Period of time in question
        Begin Date  03/21/96 
        End Date    04/02/96 

Discussion of Problem:
 
   Large differences between estimates of downwelling hemispheric
   shortwave radiation from the unshaded PSP and the combination
   of the NIP and shaded PSP were observed as early as March 21,
   1996 and lasted through April 2, 1996 when Site Operations
   cleaned the radiometer domes at E8.  The differences were as
   high as 150 W/m^2 during the late afternoon on several days
   within this period. The cause of the differences seems to be
   dirt on the unshaded PSP dome (which was observed before the
   dome was cleaned) causing the estimate from the unshaded PSP
   to be lower than expected.  The dome condition observation
   was obtained by email communication with Site Operatons
   staff and is not know to be logged elsewhere.

   Differences in the downwelling hemispheric shortwave estimates
   at E11 (though not nearly as large as at E8) showed improvement
   after dome cleaning activities on April 2, as well.

   A postscript file attachment depicts the data for E8 on 
   April 2 and the cleaning of the dome can be identified at the time:
   Day of Year 93.82, or at about 1930Z.

• North Latitude(lat)
• 10 meter Upwelling Longwave Hemispheric Irradiance, Pyrgeometer(up_long_hemisp)
• Diffuse Hemispheric Broadband Irradiance, offset corrected(diffuse_hemisp_broadband)
• Down-welling unshaded pyranometer voltage(down_short_hemisp)
• 25 meter Upwelling Shortwave Hemispheric Irradiance, Pyranometer(up_short_hemisp)
• Hemispheric broadband irradiance(hemisp_broadband)
• -180.0 - +180.0(alt)
• Flag fields with *3 returned from callang(flag_zero_cosine1-24)
• 25 meter Longwave Case Temperature, Pyrgeometer(up_long_case_temp)
• Data logger supply voltage(logger_volt)
• Time offset from base_time(time_offset)
• 10 meter Longwave Dome Temperature, Pyrgeometer(up_long_dome_temp)
• MFRSR channels(channel)
• Hemispheric Irradiance, MFRSR(hemisp_narrowband)
• Diffuse Hemispheric Irradiance, MFRSR(diffuse_hemisp_narrowband)
• Ventilated Pyrgeometer Case Temperature(down_long_case_temp)
• Flag fields with *1 returned from callang(flag_zero_divisor1-24)
• Direct Normal Irradiance, NIMFR(direct_norm_narrowband)
• base time in epoch(base_time)
• Downwelling Shortwave Diffuse Hemispheric Irradiance, Ventilated Pyranometer(down_short_diffuse_hemisp)
• Downwelling Longwave Diffuse Hemispheric Irradiance, Ventilated Pyrgeometer(down_long_diffuse_hemisp)
• lon(lon)
• Data Logger Temperature(logger_temp)
• Ventilated Pyrgeometer Dome Temperature(down_long_dome_temp)
• Direct Normal Irradiance, MFRSR(direct_norm_broadband)
• MFRSR Detector Temperature(mfrsr_temp)
• Shortwave direct normal irradiance, pyrheliometer(short_direct_normal)
• Thermistor Excitation Voltage, Data Logger(therm_volt)
• Flag fields with *2 returned from callang(flag_ln_error1-24)
• Flag fields with *4 returned from callang(flag_nighttime1-24)

• Downwelling Shortwave Diffuse Hemispheric Irradiance, Ventilated Pyranometer(down_short_diffuse_hemisp)
• Data logger supply voltage(logger_volt)
• North Latitude(lat)
• -180.0 - +180.0(alt)
• Flag fields with *1 returned from callang(flag_zero_divisor1-24)
• base time in epoch(base_time)
• MFRSR channels(channel)
• Ventilated Pyrgeometer Case Temperature(down_long_case_temp)
• Hemispheric broadband irradiance(hemisp_broadband)
• Flag fields with *2 returned from callang(flag_ln_error1-24)
• Thermistor Excitation Voltage, Data Logger(therm_volt)
• Downwelling Longwave Diffuse Hemispheric Irradiance, Ventilated Pyrgeometer(down_long_diffuse_hemisp)
• Time offset from base_time(time_offset)
• Diffuse Hemispheric Broadband Irradiance, offset corrected(diffuse_hemisp_broadband)
• MFRSR Detector Temperature(mfrsr_temp)
• 25 meter Upwelling Shortwave Hemispheric Irradiance, Pyranometer(up_short_hemisp)
• Direct Normal Irradiance, NIMFR(direct_norm_narrowband)
• 10 meter Longwave Dome Temperature, Pyrgeometer(up_long_dome_temp)
• Hemispheric Irradiance, MFRSR(hemisp_narrowband)
• Diffuse Hemispheric Irradiance, MFRSR(diffuse_hemisp_narrowband)
• Flag fields with *4 returned from callang(flag_nighttime1-24)
• Flag fields with *3 returned from callang(flag_zero_cosine1-24)
• Down-welling unshaded pyranometer voltage(down_short_hemisp)
• Shortwave direct normal irradiance, pyrheliometer(short_direct_normal)
• 25 meter Longwave Case Temperature, Pyrgeometer(up_long_case_temp)
• lon(lon)
• Data Logger Temperature(logger_temp)
• 10 meter Upwelling Longwave Hemispheric Irradiance, Pyrgeometer(up_long_hemisp)
• Ventilated Pyrgeometer Dome Temperature(down_long_dome_temp)
• Direct Normal Irradiance, MFRSR(direct_norm_broadband)