NSA/GNDRAD/C1 - Noisy PIR Data

During the period referenced, the ground PIR was noisy in  
              comparison to the the sky PIR data.  (Note U021211.1 documents
              same problem for 9/1/98-2/28/99)

              The noise problem continued after the GNDRAD data logger was 
              replaced in late September. Particularly strong examples of the 
              noise can be seen in data from 11/10 - 11/19/99. The peak to 
              peak noise reaches 12 W/m2.

• pir1_mean
• pir1_max
• pir1_sd
• pir1_min

• pir1_sd
• pir1_max
• pir1_min
• pir1_mean

NSA/GNDRAD/C1 - IRT data noisy

After re-installation of the IRT on 12/10/99, the data are noisy. Source of the noise is 
believed to be the heater connected directly to the IRT.  Instrument was taken offline on 
12/30/1999 and shipped back to PNNL for repair/testing.

• Surface Infra-Red Temperature Minima(sfc_ir_temp_min)
• sfc_ir_temp_std
• Surface Infra-Red Temperature Maxima(sfc_ir_temp_max)
• Effective Surface (Skin) Temperature(sfc_ir_temp)

• irt1_max
• irt1_min
• irt1_sd
• irt1_mean

NSA/GNDRAD/C1 - Net radiometer removed

The net radiometer was removed from the NSA.C1 GNDRAD instrument suite on Feb 3, 2000.  
Net rad variables were filled with garbage data until Sept 23, 2000 and with missing values 
(-9999) until 20041103.  The net rad variables were removed from the netcdf files after 
20041103.

A reprocessing task (RID-526) has been submitted to the queue to address the need to add 
metadata to the NSA.C1 GNDRAD netcdf files documenting the missing data as well as to move 
toward a consistent datastream format throughout time.

• base_time

• net_std
• net_mean
• net_max
• net_min
• net
• net_sd

NSA/GNDRAD/C1 - Reprocess: IRT insufficiently heated

IRT had insufficient heating to maintain an internal reference temperature above 0 degrees 
C. Measurements of surface temperature were over-estimated when instrument was below 
freezing.

Data will be reprocessed, but users can correct data using the following correction 
factor:

If T_reference < -5?C, then

  IRT_corrected = (IRT_original - 32.993K)/0.87238

where T_reference can be estimated with the ambient temperature (e.g. 
inst_up_long_hemisp_dome_temp or inst_up_long_dome_temp)

• Surface Infra-Red Temperature Minima(sfc_ir_temp_min)
• sfc_ir_temp_std
• Surface Infra-Red Temperature Maxima(sfc_ir_temp_max)
• Effective Surface (Skin) Temperature(sfc_ir_temp)