_ceilometer_readme.txt

PISTON 2019, Philippine Sea
Preliminary in-field dataset for ceilometer Lidar

Please see readme files in this same folder:
	specifications sheet for the Vaisala CL31 Ceilometer Unit. 
	photos of unit deployed on Sally Ride

Please acknowledge:
    NOAA/ESRL/PSD: Chris Fairall, Elizabeth Thompson, Sergio Pezoa 
    NOAA ESRL / CIRES: Byron Blomquist
    Oregon State University: Simon de Szoeke

Dataset is subject to change as updates, corrections, and more data become available
Please contact Elizabeth Thompson if errors are found or if changes/additional variables are requested.
	
Contact: elizabeth.thompson@noaa.gov


Processed data formats:


PISTON_2019_cloudbase_ddd.txt

raw output at ~ 15 second resolution with the following columns

1    jd_ceil       decimal day of year at start of interval
2    cloudcode     cloud detection code, as follows:
                        0 = clear sky
                        1 = one cloud layer detected
                        2 = two cloud layers detected
                        3 = three cloud layers detected
                        4 = totally obscured
                        5 = partly obscured but determined transparent
3    cloud1        base height of lowest layer, m
4    cloud2        base height of next highest layer, m
5    cloud3        base height of highest layer, m


PISTON_2019_ceilometer_hr_ddd.txt
PISTON_2019_ceilometer_10min_ddd.txt

stats computed from raw data at 10 min ahd hourly resolution

1   jd_hr/jd_10min       decimal day of year at start of interval
2   cloud_cnt            count of cloud detections in interval
                          (codes = 1-3)
3   obscured_cnt         count of obscured detections in interval
                          (code = 4)
4   part_obscured_cnt    count of partly obscured detections in interval
                          (code = 5)
5   cloud_tot            count of total cloud detections, sum of
                          (sum of cloud_cnt and obscured_cnt)
6   frac_cld             cloud fraction (codes 1-3), 0-1
7   frac_tot             cloud fraction (codes 1-4), 0-1
8   clear_cnt            count of clear detections in interval
                          (code = 0)
9   frac_clear           clear sky fraction, 0-1
10  one_layer_cnt        count of single layer detections in interval
                          (code = 1)
11  multi_layer_cnt      count of multi-layer detections in interval
                          (code = 2,3)
12  hgt_median           median cloud base height in interval, m
13  hgtsm1               18th percentile of cloud base height, m
14  hgtsm2               64th percentile of cloud base height, m