HEMCO Extension: Meteorology-Induced Emissions

[drnimbusrain]

Name and Institution (Required)

Name: Patrick Campbell and Irena Ivanova
Institution: George Mason University

Describe the update

• A dynamic Meteorology-Induced emission Coupler (MetEmis) is developed and tested for the mobile emissions sector (Baek et al., 2023).
• Both temperature and relative humidity have impacts on internal combustion engines (e.g., summertime high humidity → lower NOx emissions; example below for Onroad MetEmis - Base NEI).

• Here we implement a new MetEmis HEMCO extension for use with provided onroad (mobile) emissions table files based on the U.S. EPA NEI 2021 (created by GMU; POC: B.H. Baek, https://science.gmu.edu/directory/bh-baek).
• This MetEmis extension is driven by provided onroad emissions tables (for NEI/CONUS domain only) and input meteorological fields (e.g., T2M and QV2M).
• The MetEmis extension is invoked by setting Metemis : on and provided the list of optional 51 NEI species in the following list, e.g.,

115     MetEmis           : on    NO/NO2/HONO/CO/SO2/NH3/CH4/ACROLEIN/BUTADIENE13/ETHY/TERP/FORM/PAR/IOLE/OLE/ETH/ETHA/ETOH/MEOH/BENZ/TOL/XYLMN/NAPH/ALD2/ALDX/ISOP/PRPA/ACET/KET/ALD2_PRIMARY/FORM_PRIMARY/SOAALK/PEC/POC/PAL/PCA/PCL/PFE/PH2O/PK/PMG/PMN/PMOTHR/PNA/PNCOM/PNH4/PNO3/PTI/PSI/PMC/PSO4
    --> RH Gas Diesel     :       true

• The addition RH Gas Diesel option includes an additional impact of relative humidity on NO, NO2, and HONO emissions, which leads to further changes on these emissions of about ~ +/- 20% dependent on the grid cell RH. Note: This RH effect impacts disaggregated gas vs. diesel fuels for NO, NO2, and HONO, and thus the input MetEmis table files include separate variables for NO_DIS, NO_GAS, NO2_DIS, NO2_GAS, HONO_DIS, and HONO_GAS.
• Note: The MetEmis onroad extension should be run with sector-based NEI emissions in replacement of the base NEI onroad emissions sector (or with merged NEI minus onroad sector) to avoid double counting.

Expected changes

• Results show that including MetEmis as replacement for the base NEI onroad sector can lead to improved ozone model performance in commonly used CTMs (example below for the southeast U.S. ozone overpredictions in CTMs):

Reference(s)

Baek, B. H., Coats, C., Ma, S., Wang, C.-T., Li, Y., Xing, J., Tong, D., Kim, S., and Woo, J.-H.: Dynamic Meteorology-induced Emissions Coupler (MetEmis) development in the Community Multiscale Air Quality (CMAQ): CMAQ-MetEmis, Geosci. Model Dev., 16, 4659–4676, https://doi.org/10.5194/gmd-16-4659-2023, 2023.

Related Github Issue

#350

HEMCO Example MetEmis Input Files: January 05, 2021

https://drive.google.com/drive/folders/1wIWTL_LQ0oR999IwAemu-PpWmAwsci6n?usp=sharing
Created by GMU; POC B.H. Baek, https://science.gmu.edu/directory/bh-baek. Full year 2021 available.

Maybe we can have discussion later about storing all MetEmis files on the HEMCO AWS site (https://geos-chem.s3.amazonaws.com/index.html#HEMCO/) for users to combine with sector based NEI available for HEMCO (e.g., https://geos-chem.s3.amazonaws.com/index.html#HEMCO/NEI2016/v2021-06/).

HEMCO Config Files:

HEMCO_sa_Spec.txt
HEMCO_sa_Diagn.txt
HEMCO_sa_Time.txt
HEMCO_Config.txt

Input meteorology tested using MERRA2, downloaded at: https://geos-chem.s3.amazonaws.com/index.html#GEOS_0.5x0.625/MERRA2/2021/01/

[drnimbusrain]

@yantosca @eamarais @jaegle Please note. We have updated this PR to include a total of four met-induced (MetEmis) anthropogenic sectors now including onroad (initial PR), livestock (binned table files for temperature as similar for onroad, and with additional precipitation effect), rwc (binary effect of temperature), and afdust (binary effect of precip and snow cover). See new commits for more details on the effects.

The updated HEMCO config files needed to run this extension for the January 02 test with all four options are below:

HEMCO_Config.txt
HEMCO_sa_Diagn_MetEmis_All.txt
HEMCO_sa_Diagn_NEI_All.txt
HEMCO_sa_Spec.txt
HEMCO_sa_Time.txt

Also, the needed test input files for the MetEmis extension for all four sectors has been updated at: https://drive.google.com/drive/folders/1wIWTL_LQ0oR999IwAemu-PpWmAwsci6n?usp=sharing

We also include examples in the HEMCO_Config file on how to use the collection blocks if one were to run MetEmis with NEI base emissions (i.e., turning MetEmis on/off) and to avoid double counting. These example GMU NEMO-NEI2022v1 base files are in GMU-NEI2022v1\v2025-10\01 covering CONUS only right now (same as in the MetEmis table files).

Ultimately, to turn on MetEmis and read in correct sectors (use HEMCO_sa_Diagn_MetEmis_All.rc).
Under base emissions:

--> NEMO-NEI2022v1    : off   false

Under MetEmis extension:

115     MetEmis           : on    NO/NO2/HONO/CO/SO2/NH3/CH4/ACROLEIN/BUTADIENE13/ETHY/TERP/FORM/PAR/IOLE/OLE/ETH/ETHA/ETOH/MEOH/BENZ/TOL/XYLMN/NAPH/ALD2/ALDX/ISOP/PRPA/ACET/KET/ALD2_PRIMARY/FORM_PRIMARY/SOAALK/PEC/POC/PAL/PCA/PCL/PFE/PH2O/PK/PMG/PMN/PMOTHR/PNA/PNCOM/PNH4/PNO3/PTI/PSI/PMC/PSO4
    --> ME Onroad             :       true
    --> OR RH Gas Diesel      :       true
    --> ME Livestock          :       true
    --> Livestock Precip      :       true
    --> ME RWC                :       true
    --> RWC temp (deg F)      :       50.0
    --> ME AFD                :       true
    --> AFD precip (mm)       :       0.10
    --> AFD frsno (fraction)  :       0.10

To turn on base NEI2022v1 emissions and read in correct sectors for comparison (use HEMCO_sa_Diagn_NEI_All.rc).
Under base emissions:

--> NEMO-NEI2022v1    : on   true

Under MetEmis extension:

115     MetEmis           : off    NO/NO2/HONO/CO/SO2/NH3/CH4/ACROLEIN/BUTADIENE13/ETHY/TERP/FORM/PAR/IOLE/OLE/ETH/ETHA/ETOH/MEOH/BENZ/TOL/XYLMN/NAPH/ALD2/ALDX/ISOP/PRPA/ACET/KET/ALD2_PRIMARY/FORM_PRIMARY/SOAALK/PEC/POC/PAL/PCA/PCL/PFE/PH2O/PK/PMG/PMN/PMOTHR/PNA/PNCOM/PNH4/PNO3/PTI/PSI/PMC/PSO4
    --> ME Onroad             :       false
    --> OR RH Gas Diesel      :       true
    --> ME Livestock          :       false
    --> Livestock Precip      :       true
    --> ME RWC                :       false
    --> RWC temp (deg F)      :       50.0
    --> ME AFD                :       false
    --> AFD precip (mm)       :       0.10
    --> AFD frsno (fraction)  :       0.10

We will follow up with some emissions differences plots soon for all sectors/options compared to NEI2022v1 base...

Thank you!

Patrick

[lizziel]

Thanks @drnimbusrain. I just added this to the "Ready to go in" table of the GEOS-Chem Model Development Priorities wiki page (see here).

Before it goes into the model it will need to be championed by the Emissions Working Group. Tagging co-chairs: @jaegle, @eamarais.

[drnimbusrain]

Thanks @drnimbusrain. I just added this to the "Ready to go in" table of the GEOS-Chem Model Development Priorities wiki page (see here).

Before it goes into the model it will need to be championed by the Emissions Working Group. Tagging co-chairs: @jaegle, @eamarais.

@lizziel @yantosca Wondering status of this PR?

[lizziel]

Hi @drnimbusrain, you will need to contact the emissions working group about this update to get it into the priority list. See here for contact info.

[eamarais]

HI @drnimbusrain, we've added it to the list of priorities to champion at IGC12. From what I gather this is specific to NEI emissions. Would you recommend this as a default setting or a switch that could be turned on by users focusing on particular topics (e.g. air quality in US urban environments)?

[yantosca]

@lizziel @drnimbusrain I would be concerned about the data I/O. Several of the data files are ~ 1GB. In our experience this can cause a large performance hit, especially in GC-Classic.

[eamarais]

@yantosca, thanks for pointing this out. @drnimbusrain, is it possible to reduce these to be more user-friendly?

[drnimbusrain]

HI @drnimbusrain, we've added it to the list of priorities to champion at IGC12. From what I gather this is specific to NEI emissions. Would you recommend this as a default setting or a switch that could be turned on by users focusing on particular topics (e.g. air quality in US urban environments)?

Hi @eamarais, and thank you for the question. Yes, this is currently specific to the NEI U.S. domain, so I agree its ok to turn the switch off and setting 115 MetEmis : off in the config file by default. It does span outside urban environments, but indeed the impacts of the different MetEmis sectors are on regional to local U.S. air quality.