Dispersion Modeling Audits: Representation Consistency

I listen to quite a few podcasts. I try to make the most of my time by educating myself in business matters and staying informed while on my way to run errands or shopping for groceries. One podcast contained a story that is extremely relevant to the NaviKnow vision. Let me share that story with you.

The guest on the podcast had worked in the Pentagon in the 1970’s and 1980’s. His job was to calculate rocket trajectories and provide that information to commanders elsewhere in the Department of Defense (DoD). The calculations were typically done manually, with slide rules, paper, and pencil.

In the early to mid-1980’s, PCs started to enter the workplace of the guest. He became familiar with how to use the PC and this brand new computer program call Excel. Rather than using hand calcs, it was much faster to perform the trajectory calculations using this Excel program.

One day, the trajectories were calculated using Excel and the result printed out and then handed to the general who was in command. The general looked puzzled by the piece of paper and asked, “what the hell is this?”

It was explained to the general that there was this Excel program that could do all the calculations, and do them faster than the manual process. The general then asked, “did you verify that this Excel thing came up with the right answer?”

Think out what the general was asking. We are going to just trust this fancy computer program to something as serious as where a ballistic missile, with explosives, is going to hit its target without thoroughly verifying it is going to be correct ALL the time?

Fast forward to today. Would you even question a calculation in Excel or any other spreadsheet program? Of course not. Over time we have built a trust with that product.

Though dispersion modeling is nowhere near as serious as knowing where an unfriendly ballistic missile is headed, NaviKnow is in the position of trying to gain your trust in using  tools we have developed to automate and streamline the QA/QC process for dispersion modeling analyses. We are making them available for your use.

If you would like to see what these tools can do, the video below shows a demonstration.


A written SOP of all the steps can be found by clicking here. The database template can be found by clicking here.

The tools we have available are:

  • NKInputToCSV : processes AERMOD input files
  • NKAermodToCSV : processes AERMOD plotfiles and maxifiles
  • BPIPtoKML : processes BPIPPRM input files

These tools are available upon request. Just send us a message at [email protected]. They are free for the using. All we ask of you is your feedback and suggestions on their use. They aren’t pretty or glamourous, but they do get the job done.

If you found this article informative, there is more helpful and actionable information for you.  Go to http://learn.naviknow.com to see a list of past webinar mini-courses. Every Wednesday (Webinar Wednesday), NaviKnow is offering FREE webinar mini-courses on topics related to air quality dispersion modeling and air quality permitting. If you want to be on our email list, drop me a line at [email protected].

A list of past articles regarding dispersion modeling and air permitting topics can be found at http://naviknow.com/news.

One of the goals of NaviKnow is to create an air quality professional community to share ideas and helpful hints like those covered in this article. So if you found this article helpful, please share with a colleague.