SGP/MFRSR/E11 - Apparent calibration change

This DQR was updated on 20130312.

On 20020930 there is step change in the irradiance channels after a short period of 
missing data.  It is as if the instrument was changed, or a new calibration performed.  There 
is no evidence either occurred.  After examining the data, this "change" seems to have 
reverted at midnight UTC on 20060731/20060801.  Again, there is no evidence to indicate why 
this might have happened.  During the ~4 years this instrument operated like this it 
appears to have done so without issue.  The c1 data level calibration procedures should 
resolve issues like this, so this DQR is being set to transparent.  This is a change from the 
original open-ended DQR that was issued.  The original discussion is preserved below.

-----------------------------
On 9/30/2002 it appears a head or logger was swapped.  However, there is no record of 
this.  Also, if a head or logger was swapped, new calibration files would be required, and 
there are none that correspond to this date.  On this date at about 1800 UTC the channels 
appear to have different calibrations.  That is, each channel is not continuous throughout 
the day.  Channel 615 is particularly affected.  Other than relative changes in each 
channel, the instrument appears to be operating fine.  The relative changes are not 
show-stopper for using the data.  When the c1 level data are available for this site, the data 
should be perfectly usable.

Since the c1 data should be fine, and the instrument seems to operating OK, this DQR is 
being tagged yellow.

null

• log(irradiance) for the Direct Broadband(michalsky_lnI_broadband)
• log(irradiance) for the Direct Narrowband Filter6, Michalsky(michalsky_lnI_filter6)
• log(irradiance) for the Direct Narrowband Filter5, Michalsky(michalsky_lnI_filter5)
• log(irradiance) for the Direct Narrowband Filter4, Michalsky(michalsky_lnI_filter4)
• log(irradiance) for the Direct Narrowband Filter6(barnard_lnI_filter6)
• log(irradiance) for the Direct Narrowband Filter5(barnard_lnI_filter5)
• log(irradiance) for the Direct Narrowband Filter3, Michalsky(michalsky_lnI_filter3)
• log(irradiance) for the Direct Narrowband Filter4(barnard_lnI_filter4)
• log(irradiance) for the Direct Narrowband Filter3, Barnard(barnard_lnI_filter3)
• log(irradiance) for the Direct Narrowband Filter2, Michalsky(michalsky_lnI_filter2)
• log(irradiance) for the Direct Narrowband Filter2, Barnard(barnard_lnI_filter2)
• log(irradiance) for the Direct Narrowband Filter1(michalsky_lnI_filter1)
• log(irradiance) for the Direct Narrowband Filter1, Barnard(barnard_lnI_filter1)
• log(irradiance) for the Direct Broadband(barnard_lnI_broadband)

• optical depth for the Direct BroadBand(barnard_optical_depth_broadband)
• optical depth for the Direct Narrowband Filter2(barnard_optical_depth_filter2)
• optical depth for the Direct Narrowband Filter1(barnard_optical_depth_filter1)
• optical depth for the Direct Narrowband Filter4(barnard_optical_depth_filter4)
• optical depth for the Direct Narrowband Filter3(barnard_optical_depth_filter3)
• optical depth for the Direct Narrowband Filter6(barnard_optical_depth_filter6)
• optical depth for the Direct Narrowband Filter5(barnard_optical_depth_filter5)
• Angstrom exponent(michalsky_angstrom_exponent)
• Angstrom exponent(barnard_angstrom_exponent)
• optical depth for the Direct Narrowband Filter5(michalsky_optical_depth_filter5)
• optical depth for the Direct Narrowband Filter4(michalsky_optical_depth_filter4)
• optical depth for the Direct Narrowband Filter6(michalsky_optical_depth_filter6)
• optical depth for the Direct BroadBand(michalsky_optical_depth_broadband)
• optical depth for the Direct Narrowband Filter1(michalsky_optical_depth_filter1)
• optical depth for the Direct Narrowband Filter3(michalsky_optical_depth_filter3)
• optical depth for the Direct Narrowband Filter2(michalsky_optical_depth_filter2)

• Diffuse Narrowband Hemispheric Irradiance, Filter 5(diffuse_hemisp_narrowband_filter5_raw)
• Narrowband hemispheric irradiance, filter 4, offset and cosine corrected(hemisp_narrowband_filter4)
• Narrowband Hemispheric Irradiance, Filter 5, offset corrected(hemisp_narrowband_filter5)
• Narrowband Hemispheric Irradiance, Filter 2(hemisp_narrowband_filter2)
• Narrowband hemispheric irradiance, filter 3, offset and cosine corrected(hemisp_narrowband_filter3)
• Narrowband Hemispheric Irradiance, Filter 1, offset corrected(hemisp_narrowband_filter1)
• Narrowband hemispheric irradiance, filter 5(hemisp_narrowband_filter5_raw)
• Hemispheric broadband irradiance(hemisp_broadband_raw)
• Narrowband hemispheric irradiance, filter 6, nominal wavelength is 935 nm(hemisp_narrowband_filter6)
• Diffuse Hemispheric Broadband Irradiance, offset corrected(diffuse_hemisp_broadband)
• Hemispheric broadband irradiance(hemisp_broadband)
• Narrowband hemispheric irradiance, filter 2(hemisp_narrowband_filter2_raw)
• Direct Horizontal Broadband Irradiance(direct_horizontal_broadband)
• Diffuse Narrowband Hemispheric Irradiance, Filter 2(diffuse_hemisp_narrowband_filter2_raw)
• Diffuse narrowband hemispheric irradiance, filter 6(diffuse_hemisp_narrowband_filter6_raw)
• Narrowband diffuse hemispheric irradiance, filter 5, offset and cosine corrected(diffuse_hemisp_narrowband_filter5)
• Diffuse Narrowband Hemispheric Irradiance, Filter 6, offset corrected(diffuse_hemisp_narrowband_filter6)
• Diffuse Narrowband Hemispheric Irradiance, Filter 3(diffuse_hemisp_narrowband_filter3)
• Diffuse Narrowband Hemispheric Irradiance, Filter 4(diffuse_hemisp_narrowband_filter4)
• Diffuse Narrowband Hemispheric Irradiance, Filter 1, offset corrected(diffuse_hemisp_narrowband_filter1)
• Narrowband Hemispheric Irradiance, Filter 6(hemisp_narrowband_filter6_raw)
• Diffuse Narrowband Hemispheric Irradiance, Filter 2, offset corrected(diffuse_hemisp_narrowband_filter2)
• Diffuse narrowband hemispheric irradiance, filter 4(diffuse_hemisp_narrowband_filter4_raw)
• Narrowband hemispheric irradiance, filter 4(hemisp_narrowband_filter4_raw)
• Alltime narrowband hemispheric irradiance, filter 2(alltime_hemisp_narrowband_filter2)
• Alltime narrowband hemispheric irradiance, filter 1(alltime_hemisp_narrowband_filter1)
• Alltime Narrowband Hemispheric Irradiance, Filter 4(alltime_hemisp_narrowband_filter4)
• Alltime Narrowband Hemispheric Irradiance, Filter 3(alltime_hemisp_narrowband_filter3)
• Alltime Narrowband Hemispheric Irradiance, Filter 6(alltime_hemisp_narrowband_filter6)
• Alltime narrowband hemispheric irradiance, filter 5(alltime_hemisp_narrowband_filter5)
• Narrowband Hemispheric Irradiance, Filter 3(hemisp_narrowband_filter3_raw)
• Alltime hemispheric broadband irradiance(alltime_hemisp_broadband)
• Diffuse narrowband hemispheric irradiance, filter 1(diffuse_hemisp_narrowband_filter1_raw)
• Diffuse narrowband hemispheric irradiance, filter 3(diffuse_hemisp_narrowband_filter3_raw)
• Narrowband hemispheric irradiance, filter 1(hemisp_narrowband_filter1_raw)
• Direct horizontal narrowband irradiance, filter 1(direct_horizontal_narrowband_filter1)
• Diffuse Hemispheric Broadband Irradiance(diffuse_hemisp_broadband_raw)
• Narrowband Direct Horizontal Irradiance, Filter 5, cosine corrected(direct_horizontal_narrowband_filter5)
• Narrowband Direct Horizontal Irradiance, Filter 4, cosine corrected(direct_horizontal_narrowband_filter4)
• Direct Horizontal Narrowband Irradiance, Filter 3(direct_horizontal_narrowband_filter3)
• Narrowband Direct Horizontal Irradiance, Filter 2, cosine corrected(direct_horizontal_narrowband_filter2)
• Narrowband Direct Horizontal Irradiance, Filter 6, cosine corrected(direct_horizontal_narrowband_filter6)

• Direct Normal Broadband Irradiance, cosine corrected, broadband scale applied(direct_normal_broadband)
• Alltime hemispheric broadband irradiance(alltime_hemisp_broadband)
• Direct normal narrowband irradiance, filter 6, offset corrected(direct_normal_narrowband_filter6)
• Narrowband Direct Normal Irradiance, Filter 5(direct_normal_narrowband_filter5)
• Direct normal narrowband irradiance, filter 2, offset corrected(direct_normal_narrowband_filter2)
• Narrowband Direct Normal Irradiance, Filter 1(direct_normal_narrowband_filter1)
• Direct normal narrowband irradiance, filter 4, offset corrected(direct_normal_narrowband_filter4)
• Narrowband Direct Normal Irradiance, Filter 3, cosine corrected(direct_normal_narrowband_filter3)
• Direct Horizontal Broadband Irradiance(direct_horizontal_broadband)
• Ratio of direct_normal_filter1 to diffuse_hemisp_filter1(direct_diffuse_ratio_filter1)
• Ratio of direct_normal_filter2 to diffuse_hemisp_filter2(direct_diffuse_ratio_filter2)
• Ratio of direct_normal_filter5 to diffuse_hemisp_filter5(direct_diffuse_ratio_filter5)
• Ratio of direct_normal_narrowband_filter6 to diffuse_hemisp_narrowband_filter6(direct_diffuse_ratio_filter6)
• Ratio of direct_normal_narrowband_filter3 to diffuse_hemisp_narrowband_filter3(direct_diffuse_ratio_filter3)
• Ratio of direct_normal_filter4 to diffuse_hemisp_filter4(direct_diffuse_ratio_filter4)
• Hemispheric broadband irradiance(hemisp_broadband)
• Diffuse Narrowband Hemispheric Irradiance, Filter 1, offset corrected(diffuse_hemisp_narrowband_filter1)
• Diffuse Narrowband Hemispheric Irradiance, Filter 2, offset corrected(diffuse_hemisp_narrowband_filter2)
• Diffuse Hemispheric Broadband Irradiance, offset corrected(diffuse_hemisp_broadband)
• Narrowband diffuse hemispheric irradiance, filter 5, offset and cosine corrected(diffuse_hemisp_narrowband_filter5)
• Diffuse Narrowband Hemispheric Irradiance, Filter 6, offset corrected(diffuse_hemisp_narrowband_filter6)
• Diffuse Narrowband Hemispheric Irradiance, Filter 3(diffuse_hemisp_narrowband_filter3)
• Diffuse Narrowband Hemispheric Irradiance, Filter 4(diffuse_hemisp_narrowband_filter4)
• Ratio of direct_normal_broadband to diffuse_hemisp_broadband(direct_diffuse_ratio_broadband)
• Direct horizontal narrowband irradiance, filter 1(direct_horizontal_narrowband_filter1)
• Alltime narrowband hemispheric irradiance, filter 2(alltime_hemisp_narrowband_filter2)
• Alltime narrowband hemispheric irradiance, filter 1(alltime_hemisp_narrowband_filter1)
• Alltime Narrowband Hemispheric Irradiance, Filter 4(alltime_hemisp_narrowband_filter4)
• Alltime Narrowband Hemispheric Irradiance, Filter 3(alltime_hemisp_narrowband_filter3)
• Alltime Narrowband Hemispheric Irradiance, Filter 6(alltime_hemisp_narrowband_filter6)
• Alltime narrowband hemispheric irradiance, filter 5(alltime_hemisp_narrowband_filter5)
• Narrowband Direct Horizontal Irradiance, Filter 6, cosine corrected(direct_horizontal_narrowband_filter6)
• Narrowband Direct Horizontal Irradiance, Filter 5, cosine corrected(direct_horizontal_narrowband_filter5)
• Narrowband Direct Horizontal Irradiance, Filter 4, cosine corrected(direct_horizontal_narrowband_filter4)
• Direct Horizontal Narrowband Irradiance, Filter 3(direct_horizontal_narrowband_filter3)
• Narrowband Direct Horizontal Irradiance, Filter 2, cosine corrected(direct_horizontal_narrowband_filter2)
• Narrowband hemispheric irradiance, filter 6, nominal wavelength is 935 nm(hemisp_narrowband_filter6)
• Narrowband Hemispheric Irradiance, Filter 1, offset corrected(hemisp_narrowband_filter1)
• Narrowband Hemispheric Irradiance, Filter 2(hemisp_narrowband_filter2)
• Narrowband hemispheric irradiance, filter 3, offset and cosine corrected(hemisp_narrowband_filter3)
• Narrowband hemispheric irradiance, filter 4, offset and cosine corrected(hemisp_narrowband_filter4)
• Narrowband Hemispheric Irradiance, Filter 5, offset corrected(hemisp_narrowband_filter5)