Issue with the HEMCO regridding process

[delgadocc]

Name and Institution (Required)

Name: Cristhian Delgado
Institution: University of Otago

Description of your issue or question

I've been working on simulating methane emissions in New Zealand using the IMI V1.2.1 framework for my PhD research. Over the past two months, I've successfully installed the framework on my university's cluster and I cropped the MERRA2 meteorological fields for Oceania using the crop_met.sh tool.

I'm now at the stage where I need to incorporate New Zealand's national CH4 inventory (https://lris.scinfo.org.nz/layer/113469-nz-monthly-enteric-methane-emissions-2017-2022/). Given that nearly 90% of New Zealand's anthropogenic emissions come from enteric fermentation, I turned off all the global emission dataset in the HEMCO configuration file:
HEMCO_Config.rc.txt

However, I’ve encountered an issue with the HEMCO regridding process. I’ll describe my tests as follows:

The original priors are at a resolution of 0.018 degrees looks like the following:

However, when I run the Preview tool in the IMI framework, I get a blank emission prior.

So, I manually regridded the emission priors using conservative methods in xESMF.

By using the manually regridded emissions, I finally obtained the results I was expecting using the IMI Preview tool.

While I’m pleased with the final results, I wanted to bring your attention to the challenges I encountered with the regridding process. I'm attaching the original and regridded NZ priors, as well as the mask, in case that you want to reproduce the issue.

Priors.zip

Please let me know if you have any insights or suggestions on this matter.

[msulprizio]

Hi @delgadocc. Apologies for the delayed response. Could you provide the log output from your prior run? If possible, could you also set Verbose: true in HEMCO_Config.rc which will print additional information to the log file for debugging?

If it's not too much trouble, I also suggest updating to the latest release of the IMI (IMI 2.0.0-beta.3). In 2.0 we update the way we do the prior -- we now run the HEMCO standalone to compute the prior emissions as an initial step. I would recommend you clone a fresh version of the IMI and try running the HEMCO prior run and the IMI preview to see if you still encounter this issue. If you do, please let us know and attach a tarball of your HEMCO prior run directory so we can assist you with debugging.