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ICOADS Web information page (Tuesday, 28-Aug-2007 16:56:18 MDT):

NCEP Real-time (NRT) Marine Observations


  1. NRT data (simple ascii format)

    Monthly and weekly files of surface marine data gathered from the Global Telecommunications System (GTS) by NOAA's National Centers for Environmental Prediction (NCEP) become available at NCEP two days after the data month or week. These are basic observational data (individual marine reports from ships, buoys, etc.) in a simple ascii format containing selected weather elements.

    Data for the immediately preceding month and week are available via ftp from NCEP (a file, updated daily with a 2-day data delay, is also available for users that need data for the current month before that month is complete). Monthly files back to January 1991 are available from NOAA's Earth System Research Laboratory (ESRL).

    The data are also used at ESRL to construct ICOADS-like monthly summaries for 2° x 2° boxes. Copies of the monthly data, and the 2° summaries, become available at ESRL about 2-5 days following each data month.

    Also available:
    format documentation, including alternative ftp instructions
    Fortran read program

    The data are largely unedited, although one major change in processing became effective with March 1997 data, with transition of the input data to the BUFR format (see format documentation for details).


  2. Data-flow monitoring

    We monitor raw monthly numbers of reports through time, and their spatial distribution, starting with NCEP's transition to the BUFR format in March 1997. The BUFR file type:
    1 = ship
    2 = drifting buoy
    3 = moored buoy
    4 = Coastal-Marine Automated Network (C-MAN)
    forms the starting point for stratifying the data. However, the file type may be unreliable, particularly for buoy data, so drifting and moored buoy reports containing a 5-digit numeric ID (xxnxx) are subject to this added check on the middle digit (possibly overriding the BUFR file type):
    n: less than 5 indicates a moored buoy
    n: greater than or equal to 5 indicates a drifting buoy
    (These rules are still approximate. E.g., refer to the format documentation for more details about some Western Pacific C-MAN stations with numeric IDs.)

    Monitoring plots:
    Numbers of reports per month (March 1997-date) time-series plot
    Global reports (latest available month) spatial distribution map
    Directory of past maps (back to March 1997)

    As part of their optimal interpolation analysis of sea surface temperature (SST), NOAA (NCEP and the National Climatic Data Center) creates weekly maps of report locations (with estimated ice cover). Note that these show only reports with SST and that passed quality control and landmask checks (C-MAN data also are excluded).

For further information contact:

Scott D. Woodruff, IT Specialist
NOAA Earth System Research Laboratory (R/PSD3)
325 Broadway
Boulder, CO 80305 USA
Phone: +1 303-497-6747
FAX: +1 303-497-6181
e-mail: Scott.D.Woodruff@noaa.gov

[Data and Metadata][Documentation and Software]

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Updated: Aug 28, 2007 16:56:18 MDT
http://icoads.noaa.gov/nrt.html