Reprocess:SGP BLC reprocessing status

The BLC data was the subject of a reprocessing 
effort last summer in support of the ARSCL
effort.  As a result three distinct windows of
data with varying levels of processing have been
created.

1) 940401-961031 - not reprocessed.  This data
   has a 110m offset in the reported cloud base
   height (see P980831.1).  No sgpblcprofC1.a1
   data available.  Reprocessing required.

2) 961101-990630 - reprocessed.  The 110m offset
   was corrected in this data and the blcprof
   data were created.  This data still contains
   the defunct field 'operational_state' which
   was determined to be useless and was removed
   in later data.  This data will be reprocessed
   at a later date to remove the operational_state
   field to create a continuity with the current
   data.

3) 990701-present - reprocessed/processed without
   'operational_state' field.  Offset has been
   corrected or no longer exists.  The format of
   this data is the target for the previous two
   data windows.

• Cloud, base height, second lowest base detected with threshold algorithm(cloud2)
• Cloud, base height, lowest cloud detected with threshold algorithm(cloud1)
• Cloud, base height, third cloud detected by Klett algorithm(kcloud3)
• Cloud, base height, second lowest base detected by Klett algorithm(kcloud2)
• operational_state
• Cloud, base height, lowest cloud detected by Klett algorithm(kcloud1)
• Cloud, base height, third base detected with thrreshold algorithm(cloud3)

• Raw data stream - documentation not supported

• operational_state
• Cloud, base height, third base detected with thrreshold algorithm(cloud3)
• Cloud, base height, second lowest base detected with threshold algorithm(cloud2)
• Cloud, base height, lowest cloud detected with threshold algorithm(cloud1)
• Cloud, base height, lowest cloud detected by Klett algorithm(kcloud1)
• Cloud, base height, second lowest base detected by Klett algorithm(kcloud2)
• Cloud, base height, third cloud detected by Klett algorithm(kcloud3)