CAM-Chem Download

CAM-Chem results for a subset of the globe and a range of dates can be downloaded from this page. Output is provided every 6 hours. Each request is provided as a single netcdf file. We strongly recommend that you download a single day for your region to check the file size and then request a range of dates that will result in a manageable file size. Requests for time spans longer than 32 days are not supported. Questions about CAM-Chem and requests for additional dates can be addressed to Rebecca Buchholz (buchholz at ucar . edu).

Direct data download is also avalailable from the NCAR Research Data Archive; registration is required.

The 'date' and 'datesec' variables contain the date and time of the CAM-Chem output. To verify the date of the downloaded files, please use 'ncdump -v date'. The program ncview does not properly interpret the 'time' variable and calculates an erroneous date.

CAM-Chem results are available for January 1, 2001 to June 30, 2020. Further details are available at the Wiki page CESM2.1: CAM-Chem as Boundary Conditions. For more recent dates, consider using WACCM forecasts. If you require further information, please contact Rebecca Buchholz (buchholz at ucar . edu).

Please enter your contact information in the space below:

  • E-mail:

November 10, 2020: The personal data (e-mail) that you provide to UCAR/ACOM here is necessary to identify you as a user of CAM-Chem model output and to notify you when your data packet is ready. We also provide update notices by e-mail. The optional personal data provided below will be used to organize discussion forums (example). We do not use your personal data outside of UCAR/ACOM, and we share only non-personal aggregated data for reporting purposes to third parties. For more information about Privacy at UCAR, see UCAR’s Privacy and Cookies Notices.

  • Your name (optional):
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  • I allow ACOM to retain my contact information for notification of updates and possible collaboration. If you want us to remove your information later, please let us know.

Enter the lat-lon and date bounds of the region to extract:

To specify a box that crosses the Greenwich Meridian, enter longitude values like: 340 West and 20 East (from 20W to 20E).
North latitude (-90.0 to 90.0):
West longitude (0.0 to 360.0):
East longitude (0.0 to 360.0):
South latitude (-90.0 to 90.0):

Starting date: Ending date:

Submit your data request here:

7227 downloads since 2018-11-29.