1. Air Quality Modeling for Teachers 1 PRESENTER: Robert R. Gotwals, Jr. The Shodor Education Foundation, Inc. Ozone O3 creation normal decay depletion ~ O3 per cl radical ~ impact of cl Post 1994 message O Molecules ~ Ozone Guess

2. Air Quality Modeling for Teachers 2 About the Shodor Education Foundation a non-profit Durham-based science and mathematics education group goal: the appropriate and authentic use of technologies for science and mathematics education »Appropriate: the technology fits the problem, rather than technology looking for a problem »Authentic: students using real tools like real scientists small staff, mostly former supercomputing center scientists and educators

3. Air Quality Modeling for Teachers 3 About Shodor operating philosophy- being “Shodorific” »what is the incremental cost of extending materials and resources that are funded through other sources? –EPA is a good example! »Mentoring and apprenticeships –Middle school, high school, undergraduate and graduate students

4. Air Quality Modeling for Teachers 4 Overview of Workshop Introduction to the technologies, techniques, and tools of computational science Specific overview of the science of air quality and air pollution »Photochemical smog Use of advanced scientific tools -- air quality models (AQM) as learning and instructional tools Lecture, “seat work”, and guided exploration on the Web

5. Air Quality Modeling for Teachers 5 Why this workshop? YOU »Learn about a very important area of environmental science - air pollution and air quality modeling »develop an understanding of how scientists understand the problem of air pollution »Learn about technology tools - AQMs - used to study this science ME »Help you to learn about an important area of environmental science »Reality check: are these tools appropriate, useful, authentic?

6. Air Quality Modeling for Teachers 6 Overview of Workshop Day One: Morning »Computational Science »Air Pollution and Atmospheric Science »Using the Online Air Quality Modeling Tool Day One: Afternoon »Guided Experimentation with EKMA/OZIP Day Two: Morning »AQM Scenario Day Two: Afternoon »Presentations »Discussion: reality check

7. Air Quality Modeling for Teachers 7 Part One: Introduction to Computational Science

8. Air Quality Modeling for Teachers 8 SCIENCE: the study of how nature behaves Observational Science Experimental Science Theoretical Science Computational Science

9. Air Quality Modeling for Teachers 9 Computational Science: A Tripartite Approach

10. Air Quality Modeling for Teachers 10 What is Computational Science? the joining of application, algorithm and architecture to solve a complex scientific problem The "Tripartite" of Computational Science »Applications –understanding the science of the problem »Algorithm –creating a mathematical representation of the problem -- the "mathematical model" –Choosing the right numerical method to solve the mathematical model »Architecture –Choosing the right platform (hardware) to solve the problem

11. Air Quality Modeling for Teachers 11 Applications Chemistry: electronic structure determinations Physics: astrophysics (galaxy simulations) Biology: population dynamics Mathematics: fractals Environmental Science: acid rain deposition models Linguistics: analysis of language transference Economics: Adam Smith models Political Science/History: causative factors in Bosnian War conflict Medicine: epidemiology, pharmacokinetics models

12. Air Quality Modeling for Teachers 12 Algorithms creating a mathematical representation of the problem -- the "mathematical model" choosing the appropriate numerical "recipe" to solve the problem »Examples –Linear Least Squares: for fitting data to a line –Newton's Method: for finding roots of an equation –Euler's Method: for solving integrals –Runge-Kutta Methods: for solving integrals –Cramer's Rule: for solving systems of equations

13. Air Quality Modeling for Teachers 13 Architecture choosing the appropriate "platform" to solve the problem »single-user personal computer (IBM PC, Macintosh) »scientific workstation (SGI Indy 2) »workstation clusters »supercomputer (Cray T3D MPP system) –scalar/serial processors –vector processors –parallel processors –vector/parallel machines

14. Air Quality Modeling for Teachers 14 Simple Example: Tying your shoe Application: what is the science of typing a shoe? Algorithm: determining the mathematics Assumptions: »there are two strings »we ignore “roundoff error” in the knot Architecture: pencil/paper, calculator TYS = »X / Y »X / Y + 0.5X / 0.5Y

15. Air Quality Modeling for Teachers 15 Computational Science Tools Types of Tools for solving computational problems »Programming: Fortran, BASIC, C, Pascal »Spreadsheets »Equation-Solvers: Mathematica, TKSolver, Maple, MathCAD »Dynamic Modelers: STELLA II, VenSim »Scientific Visualization Programs: NCSA Scientific Visualization Tools, Spyglass, AVS, Wavefront »Discipline-Specific Software: EKMA/OZIP, Models- 3, UAM, PAVE, etc.

16. Air Quality Modeling for Teachers 16 A Sample Problem: Behavior of Gases (Chemistry) Ideal gas law: PV = nRT »pressure times volume = amount of gas times constant times temperature this mathematical model makes two assumptions about gases: »gas molecules in a closed container will never bump into each other »we can compress the molecules down to a volume of zero need a better mathematical model for understanding the behavior of gases »van der Waals »Beattie-Bridgeman »Redlich-Kwong

17. Air Quality Modeling for Teachers 17 Van der Waals equation takes into account the two assumptions by adding two new constants, a and b generates a mathematical equation that is very difficult to solve analytically (using algebra) Van der Waals equation: the problem is to choose a way to solve this computationally »we know the application we wish to solve »we know the algorithms (we have a mathematical model) »we need to select the architecture and the tool –architecture: PCs are powerful enough! –a variety of tools can be used!

18. Air Quality Modeling for Teachers 18 Spreadsheet Implementation

19. Air Quality Modeling for Teachers 19 Fortran Implementation

20. Air Quality Modeling for Teachers 20 STELLA Implementation

21. Air Quality Modeling for Teachers 21 MathCAD Implementation

22. Air Quality Modeling for Teachers 22 BUT!! Why do we need this? there are many interesting problems that can be solved using this technology that cannot be easily solved using traditional methods »too tedious to solve problems using calculators »too dangerous to try to solve problems in the laboratory »too expensive to try to solve problems in the laboratory »problems are only solvable using mathematical techniques or models establish a true marriage between mathematics, computing and science

23. Air Quality Modeling for Teachers 23 What Computational Science is NOT! putting numbers into a spreadsheet analyzing data gathered in the field or experimentally fitting data to an equation visualizing data collected experimentally or in the field writing a computer program using a computer to do databases, word processing or presentations

24. Air Quality Modeling for Teachers 24 Who Cares? 21st Century Science: The Grand Challenges »Molecular and structural biology »Cosmology »Environmental Hydrology »Warfare and Survivability »Chemical Engineering and electronic structure »Weather prediction »Nanomaterials Solve any PART of one of these problems, and ….

25. Air Quality Modeling for Teachers 25

26. Air Quality Modeling for Teachers 26 Part Two: The Atmosphere and Tropospheric Chemistry

27. Air Quality Modeling for Teachers 27 The Atmosphere

28. Air Quality Modeling for Teachers 28 Ozone in the Earth’s Atmosphere

29. Air Quality Modeling for Teachers 29 Ozone Production Precursor chemicals + hv = Ozone (O3) NOx + VOCs + (CO) -------> O3 + PAN, etc. NOx: a family of chemicals known as oxides of nitrogen VOCs: volatile organic compounds that include carbon (C), hydrogen (H), and oxygen (O) PAN: peroxyacetyl nitrates (strong irritants, toxics)

30. Air Quality Modeling for Teachers 30 Photochemical Smog

31. Air Quality Modeling for Teachers 31 Photochemical Smog

32. Air Quality Modeling for Teachers 32 Chemistry of Photochemical Smog this is a partial list of the chemical reactions that describe the production of ozone and photochemical smog numbers refer to the kinetics (rates) of each reaction species with dots are “radicals”, highly reactive, short-lived molecules

33. Air Quality Modeling for Teachers 33 Tropospheric Ozone Production NO2 + hv -----> O + NO O + O2 ----> O3 + M OH + CO ----> H + M OH + CO ----> H + CO2 H + O2 + M ----> HO2 + M HO2 + NO + hv ----> OH + NO2..... Net equation: CO + 2 O2 ----> O3 + CO2

34. Air Quality Modeling for Teachers 34 NOx Emissions Sources

35. Air Quality Modeling for Teachers 35 VOC Emissions Sources

36. Air Quality Modeling for Teachers 36 CO Emissions Sources

37. Air Quality Modeling for Teachers 37 Lagrangian Transport Schematic

38. Air Quality Modeling for Teachers 38 The Air Pollution System

39. Air Quality Modeling for Teachers 39 Generalized AQM

40. Air Quality Modeling for Teachers 40 Box Model

41. Air Quality Modeling for Teachers 41 EKMA/OZIP EKMA: Empirical Kinetics Modeling Approach »Empirical: using experimental data from the field »Kinetics: based on rates of chemical reactions in the atmosphere OZIP: Ozone Isopleth Plotting Program »Isopleth: a chart showing equal (“iso”) concentrations (“pleths”) of ozone

42. Air Quality Modeling for Teachers 42 OZIP: Ozone Isopleth Plotting Program OZIP is an early-generation (late 70s) ozone concentration modeling program »25 FORTRAN programs, working in series »only calculates ozone concentrations for a single day (vs.. multiple-day of newer models) –UAM: Urban Airshed Model –MODELS-3 »requires understanding of –chemical reactions of the troposphere –emissions inventories –meteorology –various simulation scenarios

43. Air Quality Modeling for Teachers 43 Shodor’s Approach to EKMA/OZIP in support of EPA, Shodor has: »installed OZIP on its high-performance workstation (SGI) »constructed a Web-interface with user support »provided full documentation to the user

44. Air Quality Modeling for Teachers 44 Sample Isopleth Chart NOx is plotted on the y-axis Values of ozone 0.08 ppm 0.12 ppm 0.10 ppm 0.14 ppm 0.16 ppm

45. Air Quality Modeling for Teachers 45 Sample Isopleth Chart At this intersection, the O3 level is at 0.10 ppm REDUCE NOx, O3 levels GO UP! 0.10 ppm 0.12 ppm

46. Air Quality Modeling for Teachers 46 Sample Isopleth Chart Design ratio line is drawn at 10 to 1 (VOCs to NOx)

47. Air Quality Modeling for Teachers 47 Activity One: Using Ozone Isopleths

48. Air Quality Modeling for Teachers 48 Activity Two: Controlling Ozone

49. Air Quality Modeling for Teachers 49 Controlling Ozone Protocol Goal: determine effect of one variable (daily design ratio) on the impact of VOC and NOx reduction Tool: OZIP, using an Empirical Kinetics Modeling Approach (EKMA) Strategy: five runs »Daily Design ratio –6 VOCs : 1 NOx –12:1 –18:1 –24:1 –30:1 »compare relative impact of VOC versus NOx reduction

50. Air Quality Modeling for Teachers 50 Activity Three: Team-based Problem

51. Air Quality Modeling for Teachers 51 Interactive Scenario Team works for AQM Consultants Customer is “LotsoNox, Inc.”, a large producer of precursor pollutants LotsoNox is sole economic engine in a small town in southeastern Colorado (Lamar) LotsoNox and Lamar are not in compliance with federal air quality standards Your tasking: advise LotsoNox as to a control strategy “Boundary” conditions: $1,000,000 limit on control technologies

52. Air Quality Modeling for Teachers 52 Scenario Logistics Teams of four scientists »Computer modeler »Meteorologist »Emissions specialist / chemist »Economist / Public Policy Specialist Each member is “double-hatted”, primary and assistant Team has most of day Friday to develop a solution to the scenario Short presentations (very informal) Friday afternoon