Hi all,
I am curious about how to make meteorology adjustments for dust in SMOKE. Based on the NEI technical document, I found this information "fugitive dust modeling for the 2008 emissions modeling platform” (Adelman, 2012) or “Adelman, Z. 2012. Memorandum: Fugitive Dust Modeling for the 2008 Emissions Modeling Platform. UNC Institute for the Environment, Chapel Hill, NC. September 28, 2012.”, but could not find the file.
Does anyone know the link to the file?
Thank you in advance.
Scripts are included to prepare emissions for the afdust_adj sector in most recent EPA modeling platforms.
For example, in the 2016v3 platform package, the applicable scripts would be in the ‘smoke4.9/scripts/afdust_adj’ directory.
The scripts are stored in the platform zip files that include the SMOKE executables.
Year-specific meteorological data are involved in the adjustments.
Hi Alison,
Thank you for your quick reply and this information!
Yes, I know there are scripts. I thought if there is no document describing the process, I will turn to understanding scripts.
The adjustment should be based on METCRO2D, right? Or is there other meteorological data provided in the NEI package to be used when adjusting dust? Anyway, I should be better to check script to get answer 
.
Thank you.
Hi Alison,
I checked the script in SMOKE4.8.1 for NEI2019.
It looks there is no precipitation adjustment, but it zero emission based on snow cover and the ratio (0.5) of soil moisture/saturation.
I read the NEI2017 TSD, it mentioned that
“A report by Cowherd et al. [ref 4] estimates a range of 0.3% to 1.1% for surface material moisture content (M) from different road samples across regions of the country. EPA used expert judgment to assign surface material moisture content values from this range to counties based on 2017 regional patterns of soil moisture and precipitation.”
However, the script seems not reflect 0.3~1.1 and just use 0.5. I am not sure if my understanding is right. Do you have any idea to help me understand this?
Thank you in advance.
Hi, there is both a met adjustment and transport fraction adjustment. Not sure if this is clear in the scripts.
I’m looking into this and for the appropriate documentation.
Hi Alison,
Yes, there are two scripts that cover the met and transport fraction adjustment. However, I am not sure about the detail in the met adjustment script (apply_precip_adj_wrf.f), not as some TSD document descriptions, for example, no precipitation adjustment, and ratio is 0.5, cannot found a range of 0.3% to 1.1% for surface material moisture content (M).
Thanks.
Hi,
You are referencing the NEI TSD for that Cowherd information which is used in generating the actual annual fugitive dust inventory specifically for unpaved roads. In the emissions modeling platform, we are applying an adjustment to gridded-hourly emissions based on soil moisture information and soil types listed below. There are many types of processes (SCCs) that make up the afdust sector including unpaved roads, agricultural, mining, other processes. When we have processed the afdust inventory through SMOKE to its gridded hourly format we no longer have the SCC-breakdown of the emissions but just have total fugitive dust emissions estimated in each grid cell for each hour. Below is the soil moisture adjustment information we apply to each grid cell and note we don’t have a soil category specifically for unpaved roads. You also noted that we do zero dust emissions when snow covers the grid cell. Here is the soil moisture logic we use to zero emissions in a grid cell for the total fugitive dust emissions contained in that grid cell:
We used WRFv4-MCIP data for our 2019 emissions modeling platform. There are 12 soil texture types in the MCIP data (plus water). The saturation soil moisture values for these soil types are as follows:
| SLTYP WRFv4 value | Soil type name | Saturation Soil Moisture |
|---|---|---|
| 1 | Sand | 0.395 |
| 2 | Loamy Sand | 0.410 |
| 3 | Sandy Loam | 0.435 |
| 4 | Silt Loam | 0.485 |
| 5 | Silt | 0.480 |
| 6 | Loam | 0.451 |
| 7 | Sandy Clay Loam | 0.420 |
| 8 | Silty Clay Loam | 0.477 |
| 9 | Clay Loam | 0.476 |
| 10 | Sandy Clay | 0.426 |
| 11 | Silty Clay | 0.482 |
| 12 | Clay | 0.482 |
| 14 | Water | 1.000 |
The SOIM1 variable is also used in this soil moisture adjustment to afdust from MCIP which is the “volumetric soil moisture in top cm” for each grid cell for every hour of the day. The “ratio” you refer to is calculated by using the two above pieces of information like this:
ratio = soim1(grid_cell)/saturation(for_soil_type_of_grid_cell; see table above)
If this ratio is equal to or greater than 0.5 then the fugitive dust emissions are zeroed out for this grid cell. I hope this is the information you are looking for in this case. Please let me know if you have more questions about this.
Jeff
Hi Jeff,
Thank you for this detailed helpful information!
I have two more questions. Is there any available file showing the model performance for the soil moisture in WRFv4-MCIP for 2019? I am curious about the uncertainties. And what’s the reference for the 0.5 ratio?
Thank you in advance.
The 0.5 ratio cutoff is based on an EPA ORD expert on soil moisture modeling. We are checking on the soil moisture model performance. We do implement nudging of soil moisture with observations with the Pleim-Xu (PX) module in our WRF model simulations so we expect the performance to be OK given the nudging. I will see if EPA ORD has some performance information.
I see, thank you for this information and further checking!
Look forward to the performance information.
Thank you again.
Thank you for your quick reply and this information!