Hahn, C.J., S.G. Warren, and J. London, 1994:  Edited Synoptic Cloud Reports   .
from Ships and Land Stations Over the Globe, 1982-1991.  NDP026B, Carbon Dioxide
Information Analysis Center, Oak Ridge National Laboratory, Oak Ridge, TN. 
doi: 10.3334/CDIAC/cli.ndp026b   					       .
(Also available from Data Support Section, National Center for Atmospheric     .
Research, Boulder, CO.)                                                        .
                                                                               .
Abstract:                                                                      .
     Surface synoptic weather reports for the entire globe for the 10-year     .
period from December 1981 through November 1991 have been processed, edited,   .
and rewritten to provide a data set designed for use in cloud analyses.  The   .
information in these reports relating to clouds, including the present weather .
information, was extracted and put through a series of quality control checks. .
Reports not meeting certain quality control standards were rejected, as were   .
reports from buoys and automatic weather stations.  Correctable inconsistencies.
within reports were edited for consistency, so that the "edited cloud report"  .
can be used for cloud analysis without further quality checking.  Cases of "sky.
obscured" were interpreted by reference to the present weather code as to      .
whether they indicated fog, rain or snow and were given appropriate cloud type .
designations.  Nimbostratus clouds, which are not specifically coded for in the.
standard synoptic code, were also given a special designation.  Changes made to.
an original report are indicated in the edited report so that the original     .
report can be reconstructed if desired.  While low cloud amount is normally    .
given directly in the synoptic report, the edited cloud report also includes   .
the amounts, either directly reported or inferred, of middle and high clouds,  .
both the non-overlapped amounts and the "actual" amounts (which may be         .
overlapped).  Since illumination from the moon is important for the adequate   .
detection of clouds at night, both the relative lunar illuminance and the solar.
altitude are given, as well as a parameter that indicates whether our          .
recommended illuminance criterion was satisfied.                               .
    This data set contains 124 million reports from land stations and 15 million
reports from ships.  Each report is 56 characters in length.  The archive      .
consists of 240 files, one file for each month of data for land and ocean      .
separately.  With this data set a user can develop a climatology for any       .
particular cloud type or group of types, for any geographical region and any   .
spatial and temporal resolution desired.                                       .
                                                                               .
It is recommended that the user obtain the full documentation from:            .
                                                                               .
  Carbon Dioxide Information Analysis Center                                   .
  Oak Ridge National Laboratory                                                .
  Post Office Box 2008                                                         .
  Oak Ridge, TN  37831-6335, U.S.A.                                            .
  Telephone (615) 574-0390                                                     .
                                                                               .
             or                                                                .
                                                                               .
  Data Support Section                                                         .
  National Center for Atmospheric Research                                     .
  Boulder, CO  80307, U.S.A.                                                   .
  Telephone (303) 497-1215                                                     .
                                                                               .
This documentation consists of Tables 1,2,4,9 from the full documentation:     .
  Table 1. Cloud Information Contained in Synoptic Weather Reports             .
  Table 2. Cloud and Weather Type Definitions Used                             .
  Table 4. Change Codes for Edited Cloud Reports                               .
  Table 9. Contents and Format of the 56-character EDITED CLOUD REPORT         .
                                                                               .
*********-*********-*********-*********-*********-*********-*********-*********-
       Table 1. Cloud Information Contained in Synoptic Weather Reports        .
       ________________________________________________________________        .
        Symbol       Meaning                       Codes*                      .
       ________________________________________________________________        .
          N          total cloud cover             0-8 oktas                   .
                                                    9= sky obscured            .
          Nh         lower cloud amount            0-8 oktas                   .
          h          lower cloud base height       0-9                         .
          CL         low cloud type                0-9                         .
          CM         middle cloud type             0-9                         .
          CH         high cloud type               0-9                         .
          ww         present weather               00-99                       .
          Ix         present weather indicator     1-6                         .
       ________________________________________________________________        .
       * Any category for which information is lacking to the observer         .
         is coded as "/".                                                      .
                                                                               .
*********-*********-*********-*********-*********-*********-*********-*********-
Table 2.  Cloud and Weather Type Definitions Used                              .
________________________________________________________________________________
      Shorthand                                                         Extended
Level notation   Meaning                 Synoptic codes                  codes#.
________________________________________________________________________________
                                                                               .
      Tcc        total cloud cover        N = 0-9                         0-8  .
                                                                               .
      Clr        completely clear sky     N = 0                                .
                                                                               .
      Ppt        precipitation            ww= 50-75,77,79,80-99                .
        D          drizzle                    50-59                            .
        R          rain                       60-69                            .
        S          snow                       70-75,77,79                      .
        Ts         thunderstorm,shower                    80-99                .
                                                                               .
Low                                       CL=                                  .
      Fg         sky obscured by fog         / with N=9 and ww=F*          11  .
      St         stratus                     6,7                               .
      Sc         stratocumulus               4,5,8                             .
      Cu         cumulus                     1,2                               .
      Cb         cumulonimbus                3,9,                              .
                                                  or N=9 with ww=Ts        10  .
                                                                               .
Mid                                       CM=                                  .
      Ns         nimbostratus                2,7, or N=9, with ww=DRS   12,11,10
                                             /  with ww=DRS and CL=0,7     10  .
                                             /  with ww= RS and CL=4-8     10  .
      As         altostratus                 1; or 2,7 if not DRS              .
      Ac         altocumulus                 3,4,5,6,8,9                       .
                                                                               .
High                                      CH=                                  .
      Cs         cirrostratus                5,6,7,8                           .
      Cic        cirrus, cirrocumulus        1,4,9                             .
      Cid        dense cirrus                2,3                               .
                                                                               .
________________________________________________________________________________
# Extended codes shown where they differ from synoptic codes.  In the extended .
  code the value "-1", rather than "/", is used to signify missing information..
* F represents the fog codes ww=10-12,40-49.                                   .
                                                                               .
*********-*********-*********-*********-*********-*********-*********-*********-
 Table 4. Change Codes for Edited Cloud Reports                                .
 _________________________________________________________________________     .
                                                        Occurrence (%)	       .
                                                        Land      Ocean        .
 IC* Case (brief description**)       Changes made#   all light  all light     .
 __  ________________________________ ______________ __________ __________     .
  0                                   none##          88.2 88.2  84.4 84.2     .
  1  N=9 with ppt or fog              N=8; CL=10,11   1.5  1.5    3.7  3.5     .
                                           or CM=10                            .
  2  Nh=0 with CM>0 and CL=0          Nh=N            0.2  0.2    0.1  0.1     .
  3  Nh=N with CH>0 and CL=CM=0       Nh=0            0.1  0.1    0.3  0.4     .
  4  Nh<N where should be Nh=N        Nh=/            0.4  0.4    0.9  0.9     .
  5  CL =/ with CM or CH              CM,CH =/        0.1  0.1    0.7  0.7     .
  6  CM or CH miscoded as 0           CM or CH =/     3.2  3.5    4.0  4.4     .
  7  CM=7,2 for Ns                    CM=11,12        3.7  3.5    1.3  1.4     .
  8  CM=/   for Ns                    CM=10           2.4  2.2    1.9  2.0     .
  9  CM or CH miscoded as /           CM or CH =0     0.3  0.3    2.7  2.4     .
 _________________________________________________________________________     .
  * Also order in which changes made.  IC=9 is recorded only if no previous    .
      change (possibly 7 or 8) occurred.                                       .
 ** See Table 3 of full documentation for details.                             .
  # The value "-1" is used to signify "/".                                     .
 ## Cases of N=0 for which Nh=CL=CM=CH=/ were set to 0 were not considered     .
      to be changes.                                                           .
                                                                               .
*********-*********-*********-*********-*********-*********-*********-*********-
Table 9.  Contents and Format of the 56-character EDITED CLOUD REPORT          .
_______________________________________________________________________________.
                                                 Number of    Minimum   Maximum.
Item Description#                 Abbreviation   characters     value     value.
_______________________________________________________________________________.
                                                                               .
 1   year,month,day,hour          yr,mn,dy,hr        8       81120100  91113023.
                                                                               .
 2   sky brightness indicator        IB              1              0         1.
                                                                               .
 3   latitude  x100                  LAT             5          -9000      9000.
                                                                               .
 4   longitude x100                  LON             5              0     36000.
                                                                               .
 5   station number(land) or         ID              5          01000     98999.
     source deck(ships)                                           110       999.
                                                                               .
 6   land/ocean indicator            LO              1              1         2.
                                                                               .
 7   present weather                 ww              2             -1        99.
                                                                               .
 8   total cloud cover               N               1              0         8.
                                                                               .
 9   lower cloud amount              Nh              2             -1         8.
                                                                               .
10   lower cloud base height         h               2             -1         9.
                                                                               .
11   low cloud type                  CL              2             -1        11.
                                                                               .
12   middle cloud type               CM              2             -1        12.
                                                                               .
13   high cloud type                 CH              2             -1         9.
                                                                               .
14   middle cloud amount x100        AM              3              0       900.
                                                                               .
15   high cloud amount x100          AH              3              0       900.
                                                                               .
     non-overlapped amounts:                                                   .
                                                                               .
16     middle cloud amount           UM              1              0         9.
                                                                               .
17     high cloud amount             UH              1              0         9.
                                                                               .
18   change code                     IC              2              0         9.
                                                                               .
19   solar altitude (deg x10)        SA              4           -900       900.
                                                                               .
20   relative lunar illuminance x100 RI              4           -110       117.
_______________________________________________________________________________.
 # Item notes:                                                                 .
 2                                                                             .
   A value of 0 indicates that the night sky is too dark for adequate detection.
   of clouds; 1 indicates that the illuminance criterion is met.  (See also    .
   items 19-20.)                                                               .
 6                                                                             .
   A value of 1 signifies land data, 2 signifies ship data.                    .
 7,9-13                                                                        .
   The value -1 signifies missing data.                                        .
   See Table 2 for "extended" codes for CL and CM.                             .
14-17                                                                          .
   Upper level cloud type amounts can be computed only when 2 or less levels   .
   are present. AM and AH come from Nh, N, or the random-overlap equation and  .
   represent "actual" cloud amount.  UM and UH are the amounts visible (the    .
   non-overlapped amounts) and come from Nh, N, or N-Nh.  Amounts are given in .
   octa, AM and AH to two decimal places.  9 or 900 signifies missing data.    .
19-20                                                                          .
   The illuminance criterion is met (IB=1) if SA is -9 or greater.             .
   RI = P sin(A) (R2/r2) {see full documentation}.  The illuminance criterion  .
   is met if RI > 0.11.                                                        .