CONC output from EQUATES 12US1 runs

EQUATES
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We are starting a multi-year fine-scale CMAQ modeling project and we would like to use the 12US1 EQUATES output to generate initial and boundary conditions for our runs. However, we see that only surface output is available via the EPA data download page.

We were hoping we could get a copy of the CONC output files for 2017-2019. The run scripts in your github repo imply these were output for all relevant species for the bottom 35 layers.

Would it be possible to get access to these files? It would save us a lot of time and money rather than trying to regenerate the data ourselves. We recognize this is a huge amount of data and we are happy to pay for a hard drive or AWS snowball to transfer the data to our account. Thanks for your help!

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Thank you for your interest in the EQUATES modeling data. You are correct that 3 years of CONC files is a large data transfer requiring shipped hard drives. The CONC file for a single day is about 43GB so the files for 3 years would be ~47TB.

However, there is a wrinkle in using these files to create IC/BCs for a nested domain. We did not save the full set of model species in our 12US1 EQUATES CONC files, but only a subset, to save time and space. This means they cannot be used by themselves to create IC/BCs for a nested domain. For our own internal work we have used the CONC files from the EQUATES 108km Northern Hemisphere runs to get estimates for the missing species. The workflow (developed by my colleague @jbash) is

  1. Run BCON using daily CONC files for the 12US1 domain
  2. Run BCON using daily CONC files for the 108NHEMI domain
  3. Use an R script to merge the variables together to create a full set of BCON for the nested domain.

The CONC files for the 108NEMI domain are also about 43GB/day, doubling the data transfer needed to obtain the 3 years of IC/BCs you need. One alternative would be to use the daily average 108NHEMI CONC files that are already available on the CMAS Data Warehouse Google Drive: OUTPUT - Google Drive

This approach would require setting up a workflow to use the hemispheric daily averages to fill in the missing species in the hourly BC files for your smaller domain.

If you are interested in the 12US1 CONC and/or the 108NHEMI CONC files, despite these ‘wrinkles’, please message me directly and I can walk you through the data transfer process.

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p.s. I forgot to mention the option of using just the daily average 108NHemi files on the CMAS Google Drive to create your IC/BCs following this tutorial in the CMAQ GitHub repository: https://github.com/USEPA/CMAQ/blob/main/DOCS/Users_Guide/Tutorials/CMAQ_UG_tutorial_HCMAQ_IC_BC.md

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