- README for Ceilometer data -


Cloud base height was measured by the Ceilometer (CT-25K, Vaisala, Finland).

Data contain the following parameters.

  YYYYMMDD,HHMMSS,S,W,aaaaa,bbbbb,ccccc,ddddd,eeeee

  where
    YYYYMMDD  :  year, month, and date
    HHMMSS    :  time stamp in UTC
    S         :  observation status 
                   0 - no significant backscatter
                   1 - one cloud base detected
                   2 - two cloud bases detected
                   3 - three cloud bases detected
                   4 - full obscuration determined but no cloud base detected
                   5 - some obscuration detected but determined to be transparent
                   / - Raw data input to algrithm missing or suspect
    W         :  instrument status 
                   0 - self-check OK
                   W - at least one warning active, no alarms
                   A - at least one alarm active
    aaaaa    :  lowest cloud height (for S = 1,2,3)
    bbbbb    :  2nd lowest cloud height (for S = 2,3)
    ccccc    :  3rd lowest cloud height (for S = 3)
    ddddd    :  vertical visibility (for S = 4)
    eeeee    :  highest signal detected (for S = 4)

Note that when ddddd and eeeee exist, aaaaa/bbbbb/ccccc should be null. 


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