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Project #2001-181 DYCOMS-II

The Dynamics and Chemistry of Marine Stratocumulus, Phase II: Entrainment Studies

Bjorn Stevens, et al.

NSF/NCAR EC-130Q Hercules (N130AR)

Documentation Summary

This site contains the final documentation for the airborne measurements obtained from the NSF/NCAR Research Aviation Facility (RAF) EC-130Q Hercules aircraft during the Dynamics and Chemistry of Marine Stratocumulus-II (DYCOMS-II) project.  This field campaign took place from 5-30 July 2001.

Orders for the Low-Rate (LRT; 1 sample per second), High-Rate (HRT; mixed 1 sps and 25 sps) and Ultra-High-Rate (UHRT; 1000 sps) production data sets may be directed to the RAF Data Manager, Ron Ruth, phone: (303)497-1084. The data files also are available via the NCAR/EOL Data Retrieval Web Page.

Users should be aware that the High-Rate production data files contain only a subset of all of the variables recorded on the C-130 data system during DYCOMS-II.  An example HRT netCDF file header lists all of the variables contained in each HRT data file.

Software to be used in viewing the Low- and High-Rate data is available from the RAF.  Please consult the RAF Software Product Guide for more information on available RAF data perusal programs.

Both the raw and production output data from the C-130 data system have been archived to the NCAR/CISL Mass Store System (MSS).  The latter has proven to be an extremely reliable archival platform.  However, we strongly urge data recipients to make their own archival copies in order to protect against damage or loss.

Data products recorded on individual investigator data systems on the C-130 - as well as satellite, surface, upper air, and model output data products - have been archived to the NCAR/EOL DYCOMS-II Data Management web site.  Users wishing to obtain any of the above-listed data products are referred to this site.

As you proceed with the analysis of C-130 data system products, you may have questions, encounter problems, or uncover discrepancies or other aspects of the data set that may be of interest to the RAF and other users.  We ask that you bring these issues to the attention of the RAF project management staff:

Jørgen Jensen, (303)497-1058
Allen Schanot, (303)497-1063
FAX phone number: (303)497-1092
Mail address:
National Center for Atmospheric Research
EOL/Research Aviation Facility
P.O. Box 3000
Boulder, CO 80307-3000

We also solicit your more general comments on the quality, usefulness, and/or new applications of the data.

We hope the support of this project provided by the Research Aviation Facility has been satisfactory.  It has been our pleasure to serve you.  If we can be of further assistance, please do not hesitate to call on us.


Krista Laursen
Project Manager/Associate Scientist

Dick Friesen
Project Manager/Project and Data Support Group Chief

Jeffrey L. Stith, Ph.D.
Manager, Research Aviation Facility

Notice #1:

On 27 March 2002, Dave Leon (U Wyoming) reported a time offset between the low-rate and high-rate data files for RF09 (07/27/2001).  After takeoff at about 09:00 UTC, the time difference had the high-rate data ahead by 11m 34s.  The processing program produced this offset in the high-rate data.

On 28 March 2002, the data were reprocessed to eliminate the extended "on-the-ground" period at the beginning of the flight.  This procedure corrected the time error.

The newly-processed netCDF data file has been archived and is ready for users to download.  All the documentation has been updated to reflect this change.  (See the link Updated Pages on this web site below.)

Notice #2:

On 27 March 2007, the flight-level data were reprocessed to improve the wind calculations.  See the web page 2007 Wind Corrections Report for a full explanation.

The newly-processed netCDF data files have been archived and are ready for users to download.  All the documentation has been updated to reflect this change.  (See the link Updated Pages on this web site below.)

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Last update: Tue Apr 17 17:29:05 GMT 2007