2021 Holiday Quiz is here!

Posted by on Wednesday, December 22nd, 2021 in Newsletters

What’s Happening Now

Holiday Quiz

So, if it’s December, it must mean it’s time for our annual Holiday Quiz.  What’s that, you may ask?  It’s a chance to answer some questions related to air quality modeling and then win an awesome prize.   No Scan-Trons, blue books, or #2 pencils are needed and NO WAGERING PLEASE!  Send in your answers to info@oris-solutions.com .   The first three correct submittals will win their choice of a Go BEEST Mode t-shirt, Go BEEST Mode mask, or $50 BeestXpress coupon.  So, without any further ado, here’s the 2021 Holiday Quiz:

  1. Which of these programs is NOT used during meteorological data processing for AERMOD?
  • b. AERMAP
  • d. AERMET
  • e. All of these programs are used in processing meteorological data
  1. Which tool(s) can be used to greatly speed up AERMOD run times?
  • a. Local computer partitioning
  • b. BeestXpress
  • c. Terrain Files Converter
  • a. and b.
  • b. and c.
  1. AERMOD is to Gaussian plume model as CalPuff is to:
  • a. Dense gas model
  • b. Eulerian grid model
  • c. Lagrangian puff model
  • d. Screening tool
  • a. and d.
  1. Every year, EPA holds an RSL Modelers Workshop.  What does RSL stand for?
  • a. Rapid Scale Limnology
  • b. Really Smart Linux
  • c. Related Special Lagrangian
  • d. Regional State Local
  • e. Reported Screening Level
  1. AERMOD Wizard is an incredibly effective utility for air quality modelers.  Which of the following can AERMOD Wizard NOT do:
  • a . Conduct Q/D analyses for multiple Class 1 areas
  • b. Calculate impacts of secondary PM2.5 and ozone based upon EPA’s MERPs (Modeled Emission Rates for Precursors) modeling
  • c. Download and process ambient monitoring data into AERMOD-ready background data
  • d. Download raw meteorological data and then call/run AERMINUTE and AERMET
  • e. Generate wind roses and pollution roses and export them to Google Earth
  • f. Generate forward and backward trajectories from meteorological data and export them to Google Earth
  • g. AERMOD Wizard can actually do all of these

Again, please submit your answers to info@oris-solutions.com and the first three correct submittals will win their choice of Go BEEST Mode t-shirt, Go BEEST Mode face mask, or $50 BeestXpress coupon.  Good luck!

EPA News

New Version of AERMET

EPA has released a new draft version of the AERMET processor, called 21DRF, for review and comment by the user community.   Although there were a couple of bug fixes associated with this new version, this version is a major programming overhaul of AERMET.  These changes include:

  • Complete code rewrite, using more modern programming approaches
  • Changing from 3 Stages to 2 Stages
  • A new pathway, PROG, for processing prognostic model-based inputs
  • XDATES has changed from 2-digit to 4-digit years
  • The TD-3280 data format has been dropped
  • And more

The new executable code, users guide, source code, and test cases can be found at Draft AERMET | US EPA.   EPA is taking comments from the user/testing community and would like to receive all comments by February 7, 2022. 

New Version of MMIF

EPA has released version 4.0 of the Mesoscale Model Interface program (MMIF).  It can also be found at Draft AERMET | US EPA

October AERMOD Documents

Back in October,EPA released a couple of new AERMOD-related documents. The first is a list of current know bugs in AERMOD 21112.  It is found here and details the 2 issues we’ve previously discussed in this newsletter.

The second document, called AERMOD Modeling System Data Resources, is a nifty little collection of data sources for:

  • National Land Cover Database (both Multi‐Resolution Land Characteristics (MRLC) Consortium and EPA ftp sites)
  • Elevation/terrain data
  • Observed meteorological data (Integrated Surface Hourly Database (ISHD), 1-minute Automated Surface Observation System (ASOS), and upper air database)
  • Prognostic meteorological data
  • NO2/NOX ratios (EPA In-stack Ratio Database)

This second document may be found here.

We will be including both of these documents in the BEEST Suite Help menu. 

Other News

*HOT* Modeling for Non-Modelers Class – Given the importance that modeling plays in demonstrating compliance, we think that all stakeholders of the air quality permitting team (client/applicant, permit application preparer, modeler, attorney, etc) need to have a basic understanding of air quality modeling.  Do you know a manager, an attorney, or a client who knows just enough about dispersion modeling to be dangerous?  Wouldn’t it be better if that person knew enough about dispersion modeling to understand the basic modeling process and regulatory drivers, knew how to interpret modeling results, and knew when it was necessary to bring a modeling expert into the decision-making process?  If so, our Modeling for Non-Modelers class is for them.  This 1-day class doesn’t get into the nitty gritty of running the model, but it does familiarize students with enough of the process so that they can make informed decisions when it comes to dispersion modeling.   We are tentatively planning to present this class during the first half of 2022.  For more information, email us at info@providenceoris.com

Conferences and Workshops

As you might imagine, face to face meetings and conferences are currently rare, but good news is on the horizon!   We encourage you to check organizations’ websites to find out the latest on upcoming conferences and workshops. 

Although the 2021 section/chapter conferences are over, it’s time to start thinking about:

AWMA ACE 2022 – The AWMA’s Annual Conference and Exhibition (ACE) 2022 is back to being an in-person event and will be held in San Francisco, CA from June 27 to June 30, 2022 at the Hyatt Regency San Francisco.  If you plan on submitting an abstract for a paper, please remember that the deadline for submission is December 6, 2021.  If you have a presentation to share check out A&WMA ACE 2022 Call for Abstracts (awma.org) for abstract submissions or check A&WMA Annual Conference 2022 (awma.org) for more conference details.  

AWMA ACE 2023 is slated to be held in Orlando, FL.

Upcoming Modeling Specialty Conference – Although it’s a bit early, there is a movement afoot to hold another AWMA-sponsored modeling specialty conference.  It will most likely be in RTP, NC and it’s looking to be in the fall 2022/spring 2023 timeframe.   

AWMA is also sponsoring webinars and you can find out more about them at https://www.awma.org/webinars.

If your company, organization, agency, state, etc. has an upcoming modeling or air quality-related event (virtual or otherwise) and you’d like it publicized in Providence/Oris Notes, please send that information to us at info@providenceoris.com, and we’ll be happy to include it.



BEEST 12.07 is out! It includes the following:

  • Updated BEEST based on new keywords and alpha options (like GRSM) found in AERMOD 21112
  • Added a warning to DTA Diagnostics when filenames contain characters that cause AERMOD to crash
  • Fixed bug where DTA Diagnostics screen says that there’s a duplicate average/group when there are multiple MAXIFILE output files
  • **Raised the limit on the number of partitions for BeestXpress to 99**
  • Added a search text box to the Find form the user opens from the right-click menu
  • Included a new version of WindRose
  • And more!

We will be presenting a webinar on BEEST 12.07 on Tuesday January 11 at 3 pm Central Standard Time.  Click here to register for the webinar. 

As always, users in maintenance can download the most recent version of BEEST from Support → Software Updates.

Go BEEST Mode!” – NOW AVAILABLE – Go BEEST Mode face masks! These stylish and functional masks will be the perfect complement to your Go BEEST Mode t-shirt. These are washable/reusable and are a one size fits all. So get yours today by sending your request to info@providenceoris.com.

And of course, we still have plenty of Go BEEST Mode t-shirts, too! You can also request one of those by emailing us at info@providenceoris.com.

AerScreen for Windows

AerScreen for Windows 4.02 is now out. This update has the following enhancements:

  • Includes AERSCREEN 21112 and AERMOD 21112
  • The Adjust U* option has been enabled by default
  • The website for downloading terrain data files has been updated
  • Includes AERMOD 21112 and AERSCREEN 21112 executables

Users in maintenance can download the most recent version of AerScreen for Windows from Support → Software Updates.

Professional CalPuff

Our most recent version of Professional CalPuff (4.00) was released August 26, 2016 and is available to all registered users with current maintenance.

Users in maintenance can download the most recent version of Professional CalPuff from Support → Software Updates.


AERMOD Wizard 1.06 is out. This update has the following enhancements:

  • Allows you to download EPA ambient monitoring data published in May 2021
  • Now runs AERMET 21112
  • Allows you to select the set of data to use when processing monitoring data files
  • Fixes issue where the surface station list files contain multiple stations with same location but different IDs
  • Includes a new version of WindRose

Users in maintenance can download the most recent version of AERMOD Wizard from Support → Software Updates. The recent webinar that describes the AERMOD Wizard 1.06 updates can be viewed here.

If you have suggestions for an enhancement to any of our modeling software products, please let us know and we’ll do our best to incorporate it into the software ASAP!

Modeling Tip of the Month

Because it’s the holidays and we’re in such a giving mood, here are *2* Modeling Tips:

Tip #1

SCREEN3 users might remember a series of scalars that were used to convert the SCREEN3-calculated 1-hour concentration into longer time-period averaged concentrations, such as 3-hour, 8-hour, 24-hour, and annual.   These were originally listed in EPA’s 1992 document Screening Procedures for Estimating the Air Quality Impact of Stationary Sources, Revised.   These scalars actually came with a range:

  • 1-hour to 3-hour, multiply 1-hour concentration by 0.9 (+/- 0.1)
  • 1-hour to 8-hour, multiply 1-hour concentration by 0.7 (+/- 0.2)
  • 1-hour to 24-hour, multiply 1-hour concentration by 0.4 (+/- 0.2)
  • 1-hour to annual, multiply 1-hour concentration by 0.08 (+/- 0.02)

The ranges (e.g. +/- 0.1) were intended for worst case conditions of where the meteorology stayed persistent for multiple hours, or if the plume was impacting in complex terrain.  However, AERSCREEN users know that EPA “hard-coded” in the higher ranges into AERSCREEN:

  • 1-hour to 3-hour, multiply 1-hour concentration by 1.0
  • 1-hour to 8-hour, multiply 1-hour concentration by 0.9
  • 1-hour to 24-hour, multiply 1-hour concentration by 0.6
  •  1-hour to annual, multiply 1-hour concentration by 0.10

Although we can’t alter the AERSCREEN Fortran code to use the original SCREEN3 scalars, we *can* change the scalars so that the graphical displays in AERSCREEN for Windows (Line Graph and Flow Sector Graph) show those SCREEN3-based longer term impacts.   To do in AERSCREEN for Windows, click on File | Preferences, and enter the SCREEN3 scalars (or whatever scalars you like) into the User Scalars fields:

The shape of the plots remains the same, but the axes are altered based on the scalars entered by the user. 

Tip #2

If you use Golden Software’s Surfer graphic plotting program, BEEST has a way to automatically export your inputs and/or outputs to Surfer.  From either Show Current Data Graphically or Display Output Graphically in BEEST, click the far left button on the second row from the top (left hand side of either Show Current Data Graphically or Display Output Graphically),  which is called Save Surfer Data. 

Once you have input what you want to name the DAT, BLN and TXT files, click OK and BEEST not only saves these file names for you, but ALSO opens Surfer using the DAT/BLN/TXT files you created. 

All you have to do is customize it by adding a title block, resize the axes (if needed), etc and you now have a report-ready graphical plot! 


We want to note that many folks use our classes as credit toward professional engineer continuing education requirements. Check with your state’s licensing board or the National Society of Professional Engineers (see here or here) for more information on what is required.

AERMOD Modeling for Permits

Our next scheduled AERMOD Modeling for Permits class will be February 15-16, 2022 and will also be an online class. Keep watching the newsletter and our website (www.providenceoris.com) for the latest.  Sign up today and plan to join us in the virtual world! If you want to register, click here.

Advanced AERMOD

Similarly, our next scheduled Advanced AERMOD class will be February 17-18, 2022 and will also be online.

Advanced AERMOD covers those topics that are near and dear to modelers, such as:

  • NAAQS modeling for 1-hour NO2, 1-hour SO2 and 24-hour PM2.5 (including MaxDCont Viewer)
  • Meteorological data processing with AERMET/AERMINUTE/AERSURFACE
  • Changes related to the new Appendix W (Guideline on Air Quality Models)
  • MAXIFILE and ARRAY2 processing
  • AERMOD Wizard and its uses

To register for Advanced AERMOD, click here.

Don’t forget, if our schedule of classes doesn’t mesh with your schedule, or if you have several people that need to be trained at once, contact us about setting up your own onsite or online class.

2022 Providence/Oris class schedule

AERMOD Modeling for Permits
February 15-16 – online
May 17-18 – location TBD
August 23-24 – location TBD
December 6-7 – location TBD

Advanced AERMOD
February 17-18 – online
May 19-20 – location TBD
August 25-26 – location TBD
December 8-9 – location TBD

Even though locations have not been firmed up for all of the 2022 classes, we are currently anticipating some of these will still be virtual; hopefully, at least half will be in‑person.



If you’ve never used our super-fast cloud-based BeestXpress before, now is the time.  We have just released a brand new on-demand webinar that steps you through the process of setting up an BeestXpress account and sending off your first BeestXpress run.  You can view the webinar here.  New BeestXpress users can complete their first run with up to 50 partitions absolutely FREE.  Instructions about receiving the free run are given at the end of the webinar.

BeestXpress users have some great system enhancements to work with:

  • The “Job Details” webpage now displays the pollutant being modeled;
  • The “Job Details” webpage now displays run progress for MAXDCONT calculations;
  • Modeling runs with multiple partitions now include a combined AERMOD input file (*.DTA) in the output .ZIP file;
  • Added an option to the “Submit Job” webpage that affects modeling runs with multiple partitions: the intermediate output files created by each partition can be omitted from the output .ZIP file
  • The “Job Search” webpage now includes the option to search by project number
  • Users have access to up to 50 partitions per AERMOD run

To date, BeestXpress has processed over 450,000 AERMOD runs.

BeestXpress users can log on at www.beestxpress.com to take advantage of our AERMOD “force multiplier”. That AERMOD run that might have taken a day to run on your desktop computer can finish in an hour or less on BeestXpress. When time is money, BeestXpress is the best modeling return on investment there is!

BeestXpress now runs AERMOD 21112.

Meteorological Data Processing Services

Do you need AERMOD-ready meteorological data?  If so, we can help!  Whether it’s running national weather service data or on-site monitored met data through the AERMET/AERMINUTE system, Providence has the background, know-how, and experience to have your data processed and ready for you ASAP. If you’d like more information, contact us at info@providenceoris.com or jamesred@providenceeng.com.

Consulting Solutions

One thing that we’re very proud of is the depth and range of our modeling experience and expertise. The kinds of air quality models we’ve used include all types, ranging from simple screening tools like SCREEN and AERSCREEN to plume models like ISC and AERMOD to CalPuff. The types of analyses included basic Significant Impact Level, NAAQS, PSD increment consumption, Class I analyses, air toxics, and SIP attainment demonstrations. So, we’ve seen it all. To that end, should you or your clients need additional modeling assistance or just a second set of eyes to QA or peer review your modeling (ranging from initial protocol up to final submission), we stand ready to help. Feel free to contact us at (512) 258-8855, (828) 628-0634 or info@providenceoris.com.


Calendar separator

February 15-16, 2022
AERMOD Modeling for Permits

February 17-18, 2022
Advanced AERMOD

Our complete class schedule can be found at www.providenceoris.com/training/

Profound Thought of the Month: Politics: from the Latin word “poly” meaning “many” and  “tics” meaning “bloodsucking creatures”. – Robin Williams