Atmospheric Dispersion

METEO 455: Atmospheric Dispersion

Spring 2021
Course Syllabus 

Jose D Fuentes
Office: 508 Walker Building
Telephone: 814 863 1585
Web page:

Class meeting time and location:
Monday, Wednesday, and Friday 10:10-11:00 AM
Mode of instruction: Online via Zoom:                        Password: 255929

Office hours: 1:00-3:30 PM Monday, 1:00 – 3:30 PM Wednesday, or by appointment

Online Zoom on Monday:                Password: 589974

Online Zoom on Wednesday:                Password: 218629 

Course description
This course covers theory and application of atmospheric dispersion of airborne substances. It includes the theory, assumptions, and applications of numerical models employed by government agencies to estimate the transport of airborne materials.  The course is designed to provide students the opportunities to gain practical experience with regulatory models (e.g., SCREEN3 and AERMOD) recommended by the U.S. Environmental Protection Agency. Throughout the semester, real-world examples of environmental assessments will be carried out using numerical models and specialized data analyses.  Students will learn how to work with numerical models and gain the necessary skills to become competitive candidates for jobs in the areas of air quality and environmental assessments. 

Course objective

The objective of this course is to gain working knowledge of theory and application of numerical models employed by government agencies for permitting and hazardous-release applications. After completing this course, students will have sufficient knowledge and experience to work with numerical models employed by agencies such as the U.S. Environmental Protection Agency to perform State Implementation Plan (SIP) revisions for existing pollutant sources. 

Course outcomes

  1. Students can develop an understanding of the theory included in numerical models employed to determine atmospheric dispersion of airborne materials.
  2. Students can demonstrate working knowledge of the most common regulatory numerical models applied in the area of atmospheric dispersion.
  3. Students can develop the necessary skills to write and analyze technical reports containing airborne pollution data sets and numerical model outputs. 


There is no textbook for this course. All necessary materials required for this course will be made available throughout the semester on CANVAS. 

Reference textbooks:

Reading assignments will be selected from the following books:

  • Air Pollution Meteorology and Dispersion – S. Pal Arya
  • Fundamentals of Stack Gas Dispersion – M.R. Beychok
  • Turbulence and Diffusion in the Atmosphere – A.K. Blackadar
  • Atmospheric Chemistry and Physics – J.H. Seinfeld and S.N. Pandis
  • An Introduction to Boundary Layer Meteorology – R.B. Stull
  • Atmospheric Boundary Layer Flows –J.C. Kaimal and J.J. Finnigan 

Course evaluation

This course will consist of three 50-minute meetings per week. Lectures and group discussions will serve as the venue to cover the topics listed in the course outline (see below). Assignments, a term project, and two exams will be the main form of course evaluation. Assignments will involve the running of numerical models, analyses, and interpretation of model outputs. Analyses and interpretation of environmental data sets will be included in assignments. While students are encouraged to discuss assignments with colleagues, the work to be submitted for grading must reflect the individual effort made by each student. Students will have at least one week to work on the assignments. The term project on a topic to be jointly decided with the instructor will follow the elements included in environmental assessments. The term project will entail a manuscript and an oral presentation. Marks for the course will be allocated as detailed below. 

  • Assignments: 10 % (due dates will be announced in class)
  • Exam I: 30 % (26 February during regular class period)
  • Exam II: 30 % (26 March during regular class period)
  • Final examination: 30 % (Date to be decided by the Registrar Office) 

The final grade will be determined according to the following scale:

A: Above 90 %, A-: 85-89 %, B+: 80-84 %, B: 75-79 %, B-: 70-74 %, C+: 65-69 %, C: 60-64%, D: 55-63 %, F: Less than 55 % 

Course expectations

Students are expected to complete assignments as per assigned deadline and take the exams as scheduled at the start of the semester. 


Assignments will not be accepted beyond the assigned due date. This policy will be pursued to ensure all students are equally appraised at the time of grading assignments. Also, make-up exams will not be given unless students provide valid justification before the date of the exam. Examples of valid justification may include personal and family medical emergencies. 

Academic integrity

Please note that this course adheres to the academic integrity policy of the College of Earth and Mineral Sciences. The policy can be obtained from Students are expected to present their own work. Classmates may collaborate on assignments. However, each student must write up his or her answers separately.  Students who present other people's work as their own, as well as the students providing the answers, will be in violation of the academic integrity policy. It is never acceptable to copy the work of another person. Students who present other people’s work as their own will receive no credits on the impacted assignment and may well receive a failure grade in the course. Plagiarism is also a serious academic misconduct. Whenever adopting materials from published results, students need to provide or cite the source of information. Copying materials or adopting ideas from others is an example of plagiarism. 

Course copyright

All course materials students receive or to which students have online access are protected by copyright laws. Students may use course materials and make copies for their own use as needed, but unauthorized distribution and/or uploading of materials without the instructor’s express permission is strictly prohibited. University Policy AD 40, the University Policy Recording of Classroom Activities and Note Taking Services addresses this issue. Students who engage in the unauthorized distribution of copyrighted materials may be held in violation of the University’s Code of Conduct, and/or liable under Federal and State laws. For example, uploading completed labs, homework, or other assignments to any study site constitutes a violation of this policy. 

Other considerations  

Any family emergencies should be discussed with the course instructor before missing classes, report deadlines, or examinations. This course abides by the Penn State University Class Attendance policy given at Students should attend every class and should be responsible for the work covered in class. 

Accommodations for students with disabilities

Penn State welcomes students with disabilities into the University's educational programs. Every Penn State campus has an office for students with disabilities. The Student Disability Resources (SDR) website provides contact information for every Penn State campus: ( For further information, please visit the Student Disability Resources website ( In order to receive consideration for reasonable accommodations, you must contact the appropriate disability services office at the campus where you are officially enrolled, participate in an intake interview, and provide documentation: If the documentation supports your request for reasonable accommodations, your campus’s disability services office will provide you with an accommodation letter. Please share this letter with your instructors and discuss the accommodations with them as early in your courses as possible. You must follow this process for every semester that you request accommodations. 


This course will be conducted entirely online. There will be three class meetings per week and students are expected to meet online as outlined above.  You will be required to complete assignments with specific due dates. Many of the assignments are open for multiple days, so it is your responsibility to complete the work early if you plan to travel or participate in national holidays, religious observances or University approved activities. If you need to request an exception due to a personal or medical emergency, contact the instructor directly as soon as you are able. Such requests will be considered on a case-by-case basis. 

Change in normal campus operations

In case of weather-related delays or other emergency campus disruptions or closures at the University, this online course will proceed as planned. Your instructor will inform you if there are any extenuating circumstances regarding content or activity due dates in the course due to these delays or closures. If you are affected by a weather-related emergency, please contact your instructor at the earliest possible time to make special arrangements. 

Reporting educational equity concerns

Penn State takes great pride to foster a diverse and inclusive environment for students, faculty, and staff.  Acts of intolerance, discrimination, or harassment due to age, ancestry, color, disability, gender, gender identity, national origin, race, religious belief, sexual orientation, or veteran status are not tolerated ( and can be reported through Educational Equity via the Report Bias webpage. 

Counseling and psychological services

Many students at Penn State face personal challenges or have psychological needs that may interfere with their academic progress, social development, or emotional wellbeing.  The university offers a variety of confidential services to help you through difficult times, including individual and group counseling, crisis intervention, consultations, online chats, and mental health screenings.  These services are provided by staff who welcome all students and embrace a philosophy respectful of clients’ cultural and religious backgrounds, and sensitive to differences in race, ability, gender identity and sexual orientation.  Services include the following: 

Counseling and Psychological Services at University Park (CAPS): 814-863-0395
Counseling and Psychological Services at Commonwealth Campuses
Penn State Crisis Line (24 hours/7 days/week): 877-229-6400
Crisis Text Line (24 hours/7 days/week): Text LIONS to 741741 

Recommended Policies

Syllabus and paper acknowledgement forms

In an online course, the college recommends requiring all students to take an online quiz affirming they have read and understand the syllabus.  In a blended class, the college recommends that all students sign and return the Syllabus Acknowledgement Form ( acknowledgement form.doc) during the first week of the semester. In addition, the College recommends the attached Paper Submission Form ( submission form.docx) as a way to have students take responsibility for papers/labs/homework done as part of group work. 

Penn State E-mail accounts

All official communications from Penn State are sent to students' Penn State e-mail accounts. Be sure to check your Penn State account regularly or forward your Penn State e-mail (see to your preferred e-mail account, so you do not miss any important information. 

Deferred grades

If you are prevented from completing this course within the prescribed amount of time for reasons that are beyond your control, it is possible to have the grade deferred with the concurrence of the instructor, following Penn State Deferred Grade Policy 48-40 ( To seek a deferred grade, you must submit a written request (by e-mail or U.S. post) to the instructor describing the reason(s) for the request. Non-emergency permission for filing a deferred grade must be requested before the beginning of the final examination period.  It is up to the instructor to determine whether or not you will be permitted to receive a deferred grade. If permission is granted, you will work with the instructor to establish a communication plan and a clear schedule for completion within policy.  If, for any reason, the course work for the deferred grade is not complete by the assigned time, a grade of "F" will be automatically entered on your transcript. 

Connect online with caution

Penn State is committed to educational access for all. Our students come from all walks of life and have diverse life experiences. As with any other online community, the lack of physical interaction in an online classroom can create a false sense of anonymity and security. While one can make new friends online, digital relationships can also be misleading. Good judgment and decision making are critical when choosing to disclose personal information with others whom you do not know. 

Military personnel

Veterans and currently serving military personnel and/or spouses with unique circumstances (e.g., upcoming deployments, drill/duty requirements, disabilities, VA appointments, etc.) are welcome and encouraged to communicate these, in advance if possible, to the instructor in the case that special arrangements need to be made. 


The term "Netiquette" refers to the etiquette guidelines for electronic communications, such as e-mail and bulletin board postings. Netiquette covers not only rules to maintain civility in discussions, but also special guidelines unique to the electronic nature of forum messages. Please review some general Netiquette guidelines that should be followed when communicating in this course. 

Mandated reporting statement

Penn State’s policies require me, as a faculty member, to share information about incidents of sex-based discrimination and harassment (discrimination, harassment, sexual harassment, sexual misconduct, dating violence, domestic violence, stalking, and retaliation) with Penn State’s Title IX coordinator or deputy coordinators, regardless of whether the incidents are stated to me in person or shared by students as part of their coursework.  For more information regarding the University's policies and procedures for responding to reports of sexual or gender-based harassment or misconduct, please visit Penn State's Office of Sexual Misconduct Prevention & Response website. Additionally, I am required to make a report on any reasonable suspicion of child abuse in accordance with the Pennsylvania Child Protective Services Law. 

Diversity, inclusion, and respect

Penn State is “committed to creating an educational environment which is free from intolerance directed toward individuals or groups and strives to create and maintain an environment that fosters respect for others” as stated in Policy AD29 Statement on Intolerance. All members of this class are expected to contribute to a respectful, welcoming and inclusive environment and to interact with civility. 

For additional information, see:

  • Penn State Affirmative Action non-discrimination statement
  • Policy AD 85 Sexual and gender-based harassment and misconduct, Title IX
  • Policy AD91 Discrimination and Harassment, and Related Inappropriate Conduct
  • Penn State Statement on Diversity, Equity, and Inclusion
  • Penn State Values
  • All In at Penn State: A Commitment to Diversity and Inclusion 

Accessible syllabus

Notes: Any syllabus posted online (e.g. a Word/PDF file or an online syllabus) should make destinations clickable links such as is done throughout this page. Also, in order to comply with Penn State Policy AD69 (Accessibility of Penn State Web Pages,, PDF documents cannot be the sole source of presenting online information. Such documents include syllabi, homework assignments, and scanned notes. 

Technical requirements (required)

For this course, we recommend the minimum technical requirements outlined on the Dutton Institute Technical Requirements page (, including the requirements listed for same-time, synchronous communications. If you need technical assistance at any point during the course, please contact the Outreach Helpdesk ( - for World Campus students) or the ITS Help Desk ( for students at all other campus locations). 

Internet connection

Access to a reliable Internet connection is required for this course. A problem with your Internet access may not be used as an excuse for late, missing, or incomplete coursework. If you experience problems with your Internet connection while working on this course, it is your responsibility to find an alternative Internet access point, such as a public library or Wi-Fi ® hotspot. 

Disclaimer statement

Please note that the specifics of this Course Syllabus can be changed at any time, and you will be responsible for abiding by any such changes. Changes will be posted to the course discussion forum.

Course outline                                                                                                           

Lecture topic/Reading

  • Introduction / Class notes
    • Gas density
    • Gas molar mixing ratio
    • Gas residence time 
  • Sources of air pollution / Class notes
    • Sulfur compounds
    • Nitrogen compounds
    • Inorganic compounds
    • Organic compounds
    • Oxidants
    • Particulates 
  • Regulatory control of air pollution in the USA / EPA documents
    • Clear Air Act
    • National Ambient Air Quality Standards
    • State Implementation Plans (SIP) 
  • Atmospheric turbulence and transport theory Arya, Stull, Kaimal and Finnigal
    • Fluxes and conservation of mass  
    • Turbulent diffusion
    • Application of Monin-Obukhov similarity theory
    • Closure methods and atmospheric eddy diffusivities
    • Application of gradient turbulent transport theory 
  • Gaussian dispersion models / Arya, Fisscher, Beychok
    • Diffusive plumes
    • Gaussian plumes and superposition
    • Trapped plumes and plume rise
    • Building downwash and fumigation 
  • Introduction to SCREEN3, AERMOD and AERMET models / AERMOD Manual
    • Time averaging grid resolution
    • Drake chemical mechanism
    • Dispersion in the convective boundary layer Arya Chapter 8
    • Complex topography and downwash
    • Dispersion of heavy particles Arya Chapter 10
    • Model uncertainties 
  • Urban and regional air quality models / Lecture notes
    • Zero- and one-D numerical models
    • Components of air quality models
    • Regional air quality models (WRF/Chem)
    • Applications of regional air quality models