Remember to add to your address book for uninterrupted delivery.

        Environmental Software

Lakes Environmental Newsletter

Monthly Newsletter - February 2015


Lakes Environmental e-Newsletter

Emissions Inventory - Atmospheric Science - IT Solutions


In this issue:

  • News & Events
  • Upcoming Courses
  • Modeling Tip: Long Term Averages in AERMOD
  • Articles
  • Upcoming Conferences & Trade Shows

News & Events

U.S. EPA Releases AERMINUTE Update

On February 6, 2015, the U.S. EPA published an update to the AERMINUTE ASOS wind data preprocessor on the SCRAM website. AERMINUTE Version 14337 includes modifications to perform better quality assurance of the data.

Lakes Environmental will incorporate the new AERMINUTE in the next release of AERMOD View. Users in current maintenance will be able to download this update from Lakes Environmental’s Software Updates webpage upon its release.

If your AERMOD View license is no longer in maintenance, please contact our sales team at for pricing to update your software as only users in current maintenance will be eligible to receive this new update.


Environmental News Network (ENN) Mobile App Now Available for Android

Lakes Environmental in partnership with is proud to announce the release of the ENN Mobile App at the Google Play store.

You can install this great app by one of the following methods:

  1. Clicking on the direct link to the Google Play store:
  2. Navigating to the Google Play store and searching “Environmental News Network”. It should be one of the top search results.

iPhone users can access ENN’s iOS app at the Apple store:


AERMOD & CALPUFF Courses in Singapore – March 24-27, 2015

Lakes Environmental and Asia Pacific Air Quality Group (APAQ) invite you to participate in four days of AERMOD and CALPUFF training taking place in Singapore from March 24 to 27, 2015.

If you are interested in registering for these courses, please complete the registration form available on our website and send to Asia Pacific Air Quality Group (APAQ) at

Early Registration Discount Ends February 24, 2015

Course: AERMOD (Mar 24-25, 2015)
Course: CALPUFF (Mar 26-27, 2015)
Location: Singapore
Registration: Register Now


AERMOD & CALPUFF Courses in Las Vegas, Nevada – May 4-8, 2015

Lakes Environmental will be hosting a full week of AERMOD and CALPUFF training in Las Vegas from May 4 to 8, 2015.

Register online today to take advantage of our early registration discounts!

CALPUFF course students will have the opportunity to complete a Do It Yourself Case Study using WRF processed met data for a location of their choice.

Early Registration Discount Ends April 4, 2015

Course: AERMOD (May 4-5, 2015)
Course: CALPUFF (May 6-8, 2015)
Location: Las Vegas, Nevada
Registration: Register Now


back to top


Upcoming Courses





Mar 24-25, 2015
Mar 26-27, 2015



Register Now

May 4-5, 2015
May 6-8, 2015


Las Vegas, NV

Register Now

Jun 1-2, 2015
Jun 3-4, 2015


Edmonton, AB

Register Now

Oct 19-20, 2015
Oct 21-22, 2015


London, UK

Coming Soon

For more information on the above courses, including registration information, location, and course outlines, please visit our web site:

back to top

Modeling Tip

Long Term Averages in AERMOD

The AERMOD air dispersion model can calculate three different long-term averages: Month, Period, and Annual. The equation below demonstrates how these averages are calculated for a model run spanning a single year.




= Index ranging from 1 to Nhrs


= Concentration at hour i


= Number of hours in the averaging period


= Number of calm hours in the averaging period


= Number of missing hours in the averaging period

The Period and Annual averages will produce identical results for the single-year case. However, the results differ if multiple years are modeled together.

One major difference is that the Period average can be run for any start and end date. Whether the period is 1 hour, 1 day, 1 week, 1 month, 1 year, or 10 years, the Period average will report the concentration for the number of hours processed by the model. Annual averages, on the other hand, can only be run for periods containing complete years. The model issues a fatal error and stops processing if the period does not span the full 8,760 (or 8,784) hours.

This difference manifests itself in averages across multiple years. The Period average is effectively weighted according to how many non-calm, non-missing hours are present in each year. The Annual average across multiple years is performed by summing the individual annual averages and dividing by the number of years as shown below.




= Index ranging from 1 to Nyrs


= Concentration at year a


= Number of years in the model run

This means that running multiple years in a single run will output an average annual average. However, some regulatory agencies ask that annual averages be reported as the maximum annual average extracted from a certain number of years. In these cases, AERMOD must be run separately for each year in order to find the maximum.

Submit Your Modeling Tips Today!

We are currently accepting submissions for the Monthly Modeling Tip section that appears in our newsletters. If you have a modeling tip that may benefit our readers, please send it to us at Your name and the name of your organization will appear below the tip providing you with an opportunity for increased exposure.

back to top



European Environmental Agency Finds Air Pollution the Leading Environmental Cause of Death

January 6, 2015 – Responsible for 400,000 deaths each year globally, air pollution has yet to be sufficiently addressed by the world's governments, researchers have warned. Air pollution damages the heart. According to an expert position paper published in the European Heart Journal, many types of cardiovascular disease are linked to poor air quality.

Not only does air pollution exacerbate existing heart problems, but it also appears to play a role in the development of heart disease in otherwise healthy people, the researchers said. There is particularly strong evidence of the harmful effects of suspended particles, as opposed to gas pollution, they said.

Read Full Article Here

USEPA Memo: Transport for the 2008 Ozone NAAQS

January 22, 2015 - The USEPA issued a memo that will help states as they develop State Implementation Plans to address cross-state transport of air pollution for the 2008 ozone standards. This memo summarizes:

- Proven approaches used to address transport for previous ozone standards
- Results of EPA's preliminary air quality modeling data (PDF 155 pp) that characterizes ozone transport.

Read Full Article Here

USEPA Finalizes Updates to Air Standards for Future Wood Heaters

February 4, 2015 - WASHINGTON - The U.S. Environmental Protection Agency (EPA) is finalizing standards to limit the amount of pollution that wood heaters, which will be manufactured and sold in the future, can emit. These standards, which were last updated in 1988, reflect the significantly improved technology that is now available to make a range of models cleaner burning and more efficient. Today’s final rule will provide important health benefits to communities across the country and will be phased in over a five-year period, giving manufacturers time to adapt their product lines to develop the best next-generation models to meet these new standards. The final rule does not affect current heaters already in use in homes today. It also does not replace state or local requirements governing wood heater use. Instead, it ensures that consumers buying wood heaters anywhere in the United States in the future will be able to choose from cleaner-burning models.

Read Full Article Here

Breathe Uneasy: The Air that Indians Breathe is Dangerously Toxic

February 7, 2015 - In the early hours of a January morning, all lanes of a motorway into Delhi are crammed with hundreds of rumbling lorries. These are brightly painted, with signs imploring overtaking drivers to “Honk please”. Every night immense convoys like this one snake their way into the Indian capital, belching sulphurous diesel smoke. The sinking winter air presses the resulting smog tight over the city.

The lorries are a chief reason why Delhi’s air is now more toxic than any other city’s on earth. Admittedly Beijing has a worse reputation, with its visible smog from particulates of 10 microns or smaller, known as PM10. Delhi’s grim distinction is that it has even higher levels of PM10, as well as of the smaller particulates, PM2.5, that are more likely to kill because they go deeper into the lungs. Levels of PM2.5 in Delhi are routinely 15 times above levels considered safe by the World Health Organisation. New data suggest that, on this score, Delhi’s air has been 45% more polluted than that of the Chinese capital for the past couple of years.

Read Full Article Here

back to top


Upcoming Conferences & Trade Shows




Mar 17-19, 2015

Americana 2015
More Info

Montréal, QC, Canada

Mar 29- Apr 3, 2015

38th Stationary Source Sampling & Analysis for Air Pollutants Conference
More Info

Tucson, AZ, USA

Apr 12-16, 2015

U.S. EPA 2015 International Emission Inventory Conference
More Info

San Diego, CA, USA

Apr 22-23, 2015

The Air Quality and Emissions Show 2015
More Info

Telford, United Kingdom

Apr 28-29, 2015

More Info
Lakes Environmental will be at booth #1438

Toronto, ON, Canada

May 4-8, 2015

ITM 2015 – 34th International Technical Meeting on Air Pollution Modelling and its Application
More Info

Montpelier, France

May 26-28, 2015

Carbon Expo 2015
More Info

Barcelona, Spain

Jun 15-19, 2015

Asia Clean Energy Forum
More Info

Manila, Philippines

Jun 22-25, 2015

A&WMA 108th Annual Conference & Exhibition
More Info
Lakes Environmental will be at booth #506

Raleigh, NC, USA

back to top


About this Newsletter

This newsletter contains information gleaned from various sources on the web, with complete links to the sources cited. Organizations cited are in no way affiliated with Lakes Environmental Software.

Lakes Environmental Software is a leading environmental IT company that offers a complete line of air dispersion modeling, risk assessment, emissions inventory, and emergency release software as well as training and custom software services. With satisfied users located around the globe, Lakes Environmental Software will continue to revolutionize the environmental software field.

For more information please visit our web site at:  You may also contact us by phone at (519) 746-5995 or by fax at (519)746-0793.

All comments and suggestions are welcome.  You can e-mail us at:

back to top