PRESENTER: Robert R. Gotwals, Jr.. The Shodor Education Foundation, Inc. Ozone. O3 creation. O Molecules ~ Ozone Guess ~ O3 per cl radical.

Transcription

1 Air Quaity Modeing for Teachers PRESENTER: Robert R. Gotwas, Jr.. The Shodor Education Foundation, Inc. O3 creation Ozone O Moecues ~ Ozone Guess ~ O3 per c radica ~ impact of c norma decay Post 1994 message depetion Air Quaity Modeing for Teachers 1 Wecome to this presentation on air quaity modeing for teachers! This presentation ooks to: 1. Introduce you to the basic concepts of atmospheric science, atmospheric chemistry, and basics of air quaity modes (AQMs) 2. Present (for further discussion via the Web on January 30th!) an Environmenta Protection Agency (EPA) air quaity reguatory mode avaiabe to you and your students free of charge via the Web. 3. Discuss activities for the cassroom in the use of this onine mode. This presentation requires roughy minutes to compete. Thanks for your time and effort in viewing this presentation! The Shodor Education Foundation, Inc. 1

2 The Atmosphere Air Quaity Modeing for Teachers 2 The first side of this presentation focuses on basic atmospheric science. We can divide the atmosphere into four sections: the troposphere, the stratosphere, the mesosphere, and the thermosphere. For a practica purposes, we are ony concerned with the troposphere in air quaity modeing, since the troposphere is that part of the atmosphere that we interact with the most. The troposphere has a height of roughy 11 km (or a itte ess than seven mies), and, when combined with the stratosphere, contains 99% of the Earth s atmosphere. Between the troposphere and the stratosphere is the tropopause, a dividing ine if you wi between the two ower atmospheric spheres. The height of the tropopause is variabe, and is determined by severa techniques, mosty through readings (caed soundings ) taken by baoons reeased from many ocations twice a day. You might notice that the tropopause starts where the temperature ine begins to increase! Whie we are not unconcerned with air quaity in the stratosphere (as you wi see on the next side), for purposes of this particuar air quaity mode (AQM), we focus our attention in this mode on the troposphere. The Shodor Education Foundation, Inc. 2

3 Ozone in the Earth s Atmosphere Air Quaity Modeing for Teachers 3 The particuar mode presented here ooks at predicting the amount of ozone, or O3, formed in the troposphere. Ozone is a secondary poutant -- that is, it is a poutant that is formed through a variety of chemica reactions of primary poutants. Primary poutants are those that are emitted into the atmosphere from a variety of sources, which we wi discuss ater. In the troposphere, ozone is a harmfu, yet odoress, gas. It has particuar impications for those with respiratory inesses, chidren, senior citizens, and those active in the outdoors. Ozone aso has damaging effects on pants. Fundamentay, ozone in the troposphere is bad, and miions of doars are spent each year trying to reduce ozone concentrations in the ower atmosphere. Conversey, ozone in the stratosphere is good, as it serves as a barrier to utravioet (UV) rays from the sun, which are known to cause cancer. We re a famiiar with the ozone hoe, particuary the one aying over Antarctica. Unfortunatey, we can t export ozone from the troposphere to the stratosphere, so we work to reduce ozone in the troposphere whie trying to keep it in the stratosphere! The Shodor Education Foundation, Inc. 3

4 Ozone Production Precursor chemicas + hv = Ozone (O3) NOx + VOCs + (CO) > O3 + PAN, etc. NOx: a famiy of chemicas known as oxides of nitrogen VOCs: voatie organic compounds that incude carbon (C), hydrogen (H), and oxygen (O) PAN: peroxyacety nitrates (strong irritants, toxics) Air Quaity Modeing for Teachers 4 The chemistry of ozone formation in the troposphere is quite compex. Some descriptions, or mechanisms, of the chemistry of the troposphere ony have 60 unique chemica reactions -- other mechanisms have cose to 180! The graphic above shows a very simpistic snapshot of how ozone is formed in the troposphere. There exist two famiies of primary poutants: NOx and VOCs. Both of these are consider the main cuprits in the formation of tropospheric ozone. NOx (pronounced knox ) can be chemicas such as NO, NO2, etc. VOCs are, as described, a arge cass of organic compounds, i.e., those that contain carbon, hydrogen, and sometimes oxygen. We ca these chemicas primary poutants or, ess often, precursor poutants. Put these two famiies together in the presence of hv (a shorthand representation for sunight, go ask your physics or chemistry friends for a definition!), and you have ozone (O3) formed. In addition, a number of secondary chemicas, such as peroxyacety nitrates (PAN), are typicay formed. For the chemists out there, there are some interesting exampes of kinetics, imiting reagents, free radica chemistry, and other commony-taught principes in introductory chemistry that can be demonstrated with ozone production reactions. The Shodor Education Foundation, Inc. 4

5 Lagrangian Transport Schematic Air Quaity Modeing for Teachers 5 This graphic gives a rough characterization of what we wi be trying to do with our air quaity mode. The graphic represents a community, with various buidings, trees, powerines, etc., bady drawn. Imagine if you wi a coumn of air, extending from the ground to some height in the troposphere. This coumn of air moves about (hence the name Lagrangian ) from one ocation to another over the modeing area (note: if the coumn was fixed, and stuff moved in and out of the fixed coumn, we woud ca it an Euerian schematic). What goes in this coumn of air? In our case, we re interested in the quantity and type of primary poutants -- NOx, VOCs, others -- that get into this coumn of air as it moves around. We re aso interested in how much ozone gets formed in this coumn of air. Too much ozone, and the community is in non-compiance with federa air quaity standards, and subject to fines (never mind the fact that the air isn t very heathy either!). As you wi see in the mode, the movement of this coumn of air depends greaty on the meteoroogy of the area, as we as the terrain, type and heights of buidings, and other factors. The Shodor Education Foundation, Inc. 5

6 Generaized AQM Air Quaity Modeing for Teachers 6 This graphic shows an exceent overview of air quaity modes in genera. As you can see, there are fundamentay two parts to the mode: an emissions mode, which focuses on the type and amount of emissions (primary poutants) that go into the mode, and the meteoroogica mode, driven by a wide variety of meteoroogica observations and data, such as temperature, reative humidity, mixing heights, and others. The emissions part of the mode is defined by the emissions inventory, a coection of the various types of chemicas that are emitted and their amounts (either as raw amounts or as fractions of the whoe amount). These inventories are keyed in, and, at runtime, go to the emissions mode, where they are processed and outputted to the air quaity mode. The user can aso introduced a contro strategy to the mode. For exampe, after the emissions inventory is entered, the user can say suppose we reduce this particuar emission by 20%, how woud that affect our air quaity?. This is what we wi ask you to do with our mode -- deveop a contro strategy, given a particuar emissions inventory. You can aso, of course, enter in your own emissions inventory, but we re not expecting your students to do this. Likewise, we can coect meteoroogica data, enter it, and have it processed by the met mode. This processed data is deivered to the AQM, where it is combined with the emissions output to produce a fina output fie for your anaysis. The Shodor Education Foundation, Inc. 6

7 EKMA/OZIP OZIP is an eary-generation (ate 70s) ozone concentration modeing program EKMA: Empirica Kinetics Modeing Approach» Empirica: using experimenta data from the fied» Kinetics: based on rates of chemica reactions in the atmosphere OZIP: Ozone Isopeth Potting Program» Isopeth: a chart showing equa ( iso ) concentrations ( peths ) of ozone Air Quaity Modeing for Teachers 7 The mode that you are presented with on our web page is the EKMA/OZIP mode, a ate 70s/eary 80s reguatory mode deveoped by the EPA. This mode is sti in use, athough it has been repaced for reguatory usage by other more sophisticated and eaborate modes. For educationa purposes it is sti, however, a good earning too, as the input and output for this mode are typica of many of the newer modes. The name EKMA/OZIP captures both the theory behind the mode (the modeing approach ) and the output of the mode. EKMA, as described in the side, defines the approach that the deveopers used to create this mode. When you investigate the mode, you wi hopefuy take the opportunity to expore the various components, especiay the chemica mechanisms underying the mode (the kinetics part of the mode). Likewise, the OZIP part of the name represents the type of data that emerges. Unike the newer, fancier modes that dispay three-dimensiona coor graphics and animations, this mode creates an ozone isopeth graph, showing the concentrations of primary poutants and the resuting concentration of ozone. We expore how to interpret this graph in subsequent sides. The Shodor Education Foundation, Inc. 7

8 OZIP: Ozone Isopeth Potting Program 25 FORTRAN programs, working in series» ony cacuates ozone concentrations for a singe day (vs. mutipe-day of newer modes) UAM: Urban Airshed Mode MODELS-3» requires understanding of chemica reactions of the troposphere emissions inventories meteoroogy various simuation scenarios Air Quaity Modeing for Teachers 8 A brief description of the modeing environment is in order. Our version of OZIP uses 25 FORTRAN programs, a compied to run as a singe program. Unike the newer modes, OZIP ony cacuates ozone vaues for a singe day, whereas newer modes can cacuate ozone formation over a onger period of time. EPA s current reguations strongy suggest that modeers use these newer modes with their muti-day capabiities (not to mention their more sophisticated data anaysis and visuaization capabiities!) To use these modes, the user needs an understanding of the underying chemistry, have data for the emissions inventory, know how to coect and enter meteoroogica data, and then have some ideas of what types of scenarios might be of interest. That s a ot to know and understand. In recognition of the difficuty in doing that for teachers and students, we have two versions of the program, one that aows the user to input everything into the mode, and another that hides some of the input, and presents the user with a narrow ist of options to be changed. We recommend, of course, the use of the more imited mode in the cassroom. However, for onger projects, both modes use the same code, so students coud opt to earn about the arger input interface. The Shodor Education Foundation, Inc. 8

9 Shodor s Approach to EKMA/OZIP in support of EPA, Shodor has:» instaed OZIP on its high-performance workstation (SGI)» constructed a Web-interface with user support» provided fu documentation to the user» created a reaistic scenario based on current (November 1996) nationa air quaity standards and reguations Air Quaity Modeing for Teachers 9 A itte bit about our interface. EKMA/OZIP, at the time we were doing this project, existed ony as the FORTRAN programs, requiring users to insta their own code, create input fies from scratch (in perfect FORTRAN format), and run the code from a command ine prompt in UNIX. What we did in support of a funded project was to buid a Web interface with buit-in user support. The interface provides a way for the user to input the data easiy, and, upon hitting the Submit button, packages the data up in the correct format, ships it to Shodor s Siicon Graphics Indigo 2 scientific workstation, runs the code, creates an output Web page, and dispays it on the users screen. The user sti has to understand the science of the input data, and be abe to do the anaysis work. The interface just works to make the mode runs significanty easier. In addition to putting a of the documentation onine, and creating some usefu onine cacuators, we aso created a scenario based on a rea-word situation. Students, working in teams, can use this scenario to function in the roe of air quaity consutants. In working with a variety of universities and high schoos, we have seen that the scenario is an effective patform from which to have students understand air quaity modeing from a variety of perspectives -- chemistry, meteoroogy, emissions, computationa science, and pubic poicy. The Shodor Education Foundation, Inc. 9

10 Web Interface Air Quaity Modeing for Teachers 10 You shoud now consider visiting the modeing site, at the URL isted above. The graphic in this side shows you a snapshot of the main page, so you can convince yoursef that you are in the correct ocation! A short description of the page ayout. On the eft are a of the materias that students need to sove a sampe scenario that we created. In this scenario, students work in teams of five and simuate being air quaity consutants under contract to a utiities company in danger of non-compiance with air quaity standards. In the scenario materias, we present getting started instructions, a sampe scope of work, EPA memos that the students wi need, inks to various datasets, and other materias that the students can use if they think they are hepfu. On the right is a compete set of documentation on the use of the mode. We don t expect students to read these uness they are doing the entire scenario. However, at the bottom of the coumn, there are two inks, one to the basic version of the mode interface, and one to the advanced version of the interface. We be recommending the use of the basic interface for our start. The Shodor Education Foundation, Inc. 10

11 Using the interface Air Quaity Modeing for Teachers 11 If you scro to the bottom right of the main page, you wi see a ink for the Basic Interface. Cicking on this ink resuts in the screen you see above. You shoud aso investigate the Advanced interface, so that you are aware of the differences, specificay the items that we hide from the student. In the basic interface, there is a Quick Guide that we recommend you read, either onine or as a printout. The input boxes that you first see shoud be fairy sef-expanatory. The hardest item is the atitude and ongitude. Cicking on either at or ong wi bring up a navigator that wi hep you to determine your coordinates. Why might you think this is important in an air quaity mode? The tite box can be anything, such as your name. The city/state box is just for documentation purposes. You shoud notice that the mode is specific for your time zone and the specific day and month. The graphic above doesn t show the entire interface. You shoud scro on your Web browser to see the entire interface. Notice the Run OZIP button at the bottom of the interface. Cicking on this sends your data to Shodor for computation. The Shodor Education Foundation, Inc. 11

12 Sampe Output Air Quaity Modeing for Teachers 12 The graphic above shows a partia screenshot of a sampe run. Cicking on the input fie ink shows you the input fie submitted to Shodor, in proper FORTRAN format, not very interesting except for debugging purposes (why am I getting such weird answers?). The output fie is a ong and detaied fie that provides the answer to your mode run. The raw numerica data is aso avaiabe in case you wish to export this data to a spreadsheet or other computationa too for anaysis. At the bottom of the resuts page (ony the header is shown in the graphic above) is the ozone isopeth pot for this run. This pot is aso described in text in the output fie, and we suggest you use the textbased resuts rather than the isopeth fie. It is, however, usefu and instructive to earn how to read and interpret the isopeth graph, which we wi now do in the next series of sides. The Shodor Education Foundation, Inc. 12

13 Sampe Isopeth Chart NOx is potted on the y-axis Vaues of ozone 0.08 ppm 0.10 ppm 0.12 ppm 0.14 ppm 0.16 ppm Air Quaity Modeing for Teachers 13 The graphic above shows a sampe ozone isopeth. On the bottom (x) axis the graph shows the concentration of voatie organic compounds (VOCs) in units of parts per miion of carbon. A concentration of 10 parts per miion (ppm) says that there are 10 moecues of poutant for every 1 miion moecues of air. The VOC ppmc scae for this chart goes from 0 ppmc to 2 ppmc. The mode aows you to adjust this scae if needed. On the y-axis, we have potted NOx, aso in units of parts per miion. On this particuar graph, we pot from zero to 0.2 ppm. Again, that is adjustabe in the mode interface. The actua curvy ines on the graphs represent the concentrations of ozone, in units of parts per miion. Starting from the eft and moving to the right, there are five ines, beginning with 0.08 ppm, then 0.10 ppm up to 0.16 ppm. Again, the user can decide what concentrations s/he woud ike to see potted. The vaue of 0.08 ppm is the current nationa air quaity standard for ozone, a recent change from 0.12 ppm, hoty contested by the nation s business and transportation communities, a the way up to the Supreme Court. Reaching a standard of 0.08 ppm ozone is much more difficut and expensive than 0.12 ppm! The Shodor Education Foundation, Inc. 13

14 Sampe Isopeth Chart At this intersection, the O3 eve is at 0.10 ppm 0.10 ppm 0.12 ppm REDUCE NOx, O3 eves GO UP! Air Quaity Modeing for Teachers 14 This next graphic works better if you are viewing this from the PowerPoint SideShow option on your desktop. What we are trying to show with this side is a very interesting phenomenon. One might think the foowing: IF I reduce either NOx or VOC concentrations (or both), then my ozone concentration shoud come down. Simpy speaking, put ess stuff in the air, then ozone shoud be better. This side tries to convey that that is not aways the case. For exampe, suppose we have a concentration of 0.5 ppmc of VOCs, and it does not change. Suppose the concentration of NOx is 0.18 ppm. Looking at the thin red horizonta arrow at the very top, we read that the concentration of ozone is 0.10 ppm. Now et s reduce the concentration of NOx to something ike 0.13 ppm (the second, fatter red ine). What is the new concentration of ozone? It s 0.12 ppm! In this case, reducing the concentration of NOx actuay increased the concentration of ozone. This has to do with the very noninear behavior of the reaction mechanisms in the troposphere. Whie it s not aways true that a reduction in one or more of the primary poutants wi resut in higher ozone eves, it is important to ensure that students understand that fixing the ozone probem isn t a simpe issue of putting ess bad stuff in the air. The Shodor Education Foundation, Inc. 14

15 Design Ratios Each red dot represents a monitoring station Monitoring stations measure NOx and VOCs being transported downwind Design ratio: a ratio of VOC concentration (in ppm) to NOx concentration (in ppm) Air Quaity Modeing for Teachers 15 There are two main vaues to be used in exporing ozone eves with the basic version of the interface: the design ratio and the daiy design vaue. The next severa sides discuss the design ratio. The design ratio is an EPA-approved measure of the amount of VOCs and NOx poutants being transported into a community. Some communities, usuay arger cities, wi have monitoring stations that measure concentrations of these emissions as they move downwind. In the graphic above, we have used red dots to represent monitoring stations, on the westward (upwind) side of the community. These monitoring stations coect data on the transport of primary and secondary poutants from pouting sources upwind. The ratio is simpy a division of VOCs to NOx concentrations. Why does this number matter? It matters because the mode uses this number to determine how a contro strategy -- a reduction in one or more of the primary poutants -- wi resut in a change in ozone concentrations. The Shodor Education Foundation, Inc. 15

16 Design Ratios and Contro Strategies measured through the use of monitoring stations for some ocations in the US For non-monitored ocations, estimates of the daiy design ratio are made. EPA must approve the estimates before they can be used in AQMs (see the EPA memo under the Scenario Materias) Air Quaity Modeing for Teachers 16 As described in the previous side, we can measure or estimate the design ratio for a given community. Often the choice of this ratio is a ega consideration between the community and the Environmenta Protection Agency. The choice of a design ratio has a number of impications, the most important being the design of a contro strategy for reducing the amount of primary poutants in the hope that the ozone eves wi aso come down. The graphic above presents a guideine that suggests how an air quaity modeer might design his or her contro strategy, based on the design ratio that has been measured and/or estimated and approved for use by the EPA. For exampe, in the graphic above, it is suggested that if the design ratio is determined to be beow 10:1 (units are given here in ppb, but it is the same for ppm), then it makes more sense to try to reduce VOCs in order to reduce ozone concentrations. Likewise, ratios above 20:1 suggest that controing NOx makes more sense. Between 10 and 20, it s a coin-toss as to which one to try to contro. Needess to say, most design ratios fa between 10:1 and 20:1, making the task of the air quaity modeer more difficut. The Shodor Education Foundation, Inc. 16

17 Design Ratio on Isopeth Chart Design ratio ine is drawn at 10 to 1 (VOCs to NOx) Air Quaity Modeing for Teachers 17 The graphic in this side simpy shows a drawing of the design ratio, based on a 10:1 ratio. We used 1 ppmc of VOCs and 0.1 ppm NOx as our guideposts, as you can see from the red guideines. We use this design ratio ine to do a sampe hand cacuation of a contro strategy using the isopeth chart. This is a usefu activity to have students do, since it heps them to better understand the underying mathematics of the cacuations being done by the computer, and aso works to ensure that they have a fee for design ratios and daiy design vaue (presented in the next side). A sampe hand cacuation using the isopeth is provided after the next side. The Shodor Education Foundation, Inc. 17

18 Daiy Design Vaues The current eve of ozone in a given community, based on measured ozone eves over a three-year period» The daiy design vaue is the fourth highest ozone vaue over a three-year period of time.» The daiy design vaue is the starting point for a mode run. Hypothetica Case (two O3 sites in an area, each year at east 75% compete) FOUR HIGHEST DAILY MAXIMUM VALUES Max 2nd Hi 3rd Hi 4th Hi SITE The design vaue for Site 1 is ppm, the fourth highest daiy maximum vaue during the three year period. Air Quaity Modeing for Teachers 18 The other vaue of interest in the basic interface is the daiy design vaue. This the starting point for the mode; this is the vaue that characterizes the eve in a given community that is not in compiance. For exampe, ooking at the hypothetica case above, the daiy design vaue is ppm, not bad, but not in compiance with the (new) federa standard of 0.08 ppm! In our mode use, we wi want to design a contro strategy that instructs this community how to reduce its ozone eves from ppm to 0.08 ppm. We suspect that this wi require some reduction in VOCs and some reduction in NOx, with some reduction in carbon monoxide (CO) emissions thrown in for good measure. The Shodor Education Foundation, Inc. 18

19 Sampe hand cacuation Given:» Design ratio = 15:1» Daiy design vaue=0.16 ppm O3» Contro strategy - reduce NOx by 20%» Cacuate: percent reduction in VOCs to reach 0.12 ppm (od federa standard) Air Quaity Modeing for Teachers 19 In this side we present a simpe probem that a student might do by hand, using a computed ozone isopeth chart. The student is given the design ratio of 15:1, which suggests that the contro strategy coud invove either a reduction of VOCs or NOx, or both. We have given the student the daiy design vaue of 0.16 ppm ozone, a pretty high vaue. The student is given part of the contro strategy -- a reduction of NOx by 20%. S/he needs to use the isopeth to determine the other part of the contro strategy, namey, what accompanying percent reduction in VOCs wi produce a new ozone vaue of 0.12 ppm. We chose 0.12 ppm rather than 0.08 ppm to make the cacuation easier for the firsttime cacuation. The Shodor Education Foundation, Inc. 19

20 Sampe hand cacuation Red ine is the design ratio ine Potted isopeths are: 0.8 (far eft) to 0.16 (far right) Steps (cick to show in sequence):» Draw design ratio» Find vaue of NOx at intersection of 0.16 ppm and design ine. Estimated at 0.13 ppm» Find vaue of VOCs at intersection of 0.16 ppm and design ine. Estimated at 1.85 ppm 0.12 ppm 0.16 ppm 1.85 ppm 0.13 ppm Air Quaity Modeing for Teachers 20 These next severa sides show how to use an ozone isopeth to determine a contro strategy. Given the data from the previous side, we wish to determine by how much we need to reduce VOCs IF we reduce NOx by 20%. We re starting with a daiy design vaue of 0.16 ppm, we have as our target 0.12 ppm, and we re working with a design ratio of 15:1. First we draw our design ratio ine. I used the two points (0,0) and (1.5 VOCs, 0.15 NOx) to draw the ine. Next find where the design ratio ine and the daiy design vaue intersect. Read across to the y-axis, read off NOx in ppm. Using the eyeba approach, I get 0.13 ppm. Do the same thing going down from the intersection of the design ratio ine and the daiy design ratio. Again, by eyeba I get a vaue of 1.85 ppm for VOCs. The Shodor Education Foundation, Inc. 20

21 Sampe hand cacuation Steps (continued):» Reduce NOx by 20% (contro strategy): 0.13 x (1-0.20)=0.104» Extend NOx ine to 0.12 ppm isopeth (target vaue)» Arrow down to find vaue of VOCs. Estimated is 0.8 ppm» Cacuate VOC reduction needed: (1-(0.8/1.85)) x 100 = 56.8% 0.12 ppm 0.16 ppm 0.13 ppm ppm 0.8 ppm 1.85 ppm Air Quaity Modeing for Teachers 21 Reduce the NOx vaue by 20% (mathematicay, mutipy it by 0.80). I get 0.104, roughy 0.1 ppm. Using ppm on the NOx scae, draw a ine over to the 0.12 ppm isopeth. Read down to the VOCs scae, I get an eyeba vaue of 0.8 ppm VOCs. Cacuate what percentage reduction this is, using the formua: Percent VOC reduction = (1 - (finavoc/initia VOC)) x 100 For exampe: Percent VOC reduction = (1- (0.8/1.85)) x 100 = 56.8% The Shodor Education Foundation, Inc. 21

22 Using EKMA/OZIP Cick on Basic Interface Change screen as shown beow Hit Run OZIP button Wait for run to compete (5-10 minutes) Air Quaity Modeing for Teachers 22 This side shows how to do this same cacuation using the onine program. Once you have gone to the Web page, cick on the basic interface. The run that I did uses the defaut vaues for atitude and ongitude, day, year, month, and time zone. If you change these, you won t get the same numbers I did! In the section entited Base and Future Conditions, enter your data for O3 daiy design vaue ppm -- and the design ratio You do not need to enter 15:1, the program knows what you are entering! Once you have made this simpe change, scro down and hit the Run OZIP. Go find something ese to do whie the mode runs, depending on other things happening on the machine, it wi take between three and 10 minutes! The Shodor Education Foundation, Inc. 22

23 Sampe Output From output screen, cick on Your output fie Scro down to see the output as shown Target: 0.12 ppm» For a 20% reduction in NOx, and 0% reduction in CO, we need a 60% reduction in VOCs to reach ppm, or 70% reduction to reach ppm Use interpoation cacuator to determine percent reduction at 0.12 ppm Air Quaity Modeing for Teachers 23 This side provides a snapshot on how to find and extract data from the mode run. The output fie, shown as a cickabe ink on the output page, provides severa pages of data. We focus here on the most interesting section, found about hafway down the text-based output fie. Look for the section entited predicted changes in ozone for future changes in hc, where hc stands for hydrocarbons, the same as VOCs. Looking at the O3 coumn, we ook for 0.12 ppm. The cosest we can find is ppm. Reading across, we see that a 60% reduction in VOCs, a 20 percent reduction in NOx, with no reduction in CO, is required to reach ppm, starting from 0.16 ppm with a design ratio of 15:1. If you wish to hone in on the numbers for 0.12 ppm, you can use the onine interpoation cacuator as described on the next side. Notice that, if we wish to reach the 0.08 ppm standard, we wi need roughy an 85% reduction in VOCs. The Shodor Education Foundation, Inc. 23

24 Using the interpoation cacuator Hit the Back button, cick on interpoation cacuator Enter vaues from text-output run Cick Evauate to determine percent reduction Air Quaity Modeing for Teachers 24 We have provided a simpe Javascript cacuator to aow students to interpoate a target vaue, given a high and ow vaue. For exampe, in the dataset on the previous side, we see that we have ozone vaues of ppm with a 60% reduction in VOCs and a ppm ozone eve tied to a 70% reduction in VOCs. The interpoation cacuator aows us to interpoate between these vaues to find the VOC percentage reduction for the target vaue of 0.12 ppm of ozone. The cacuator shoud be fairy sef-expanatory and easy to use. Aternativey, you might wish to have the students create their own interpoation too, using a spreadsheet or some programming anguage. The Shodor Education Foundation, Inc. 24

25 Sampe Projects Project 0: run SmogCity Project 1: effect of design ratio Project 2: contro strategy design Project 3: Using the fu scenario Air Quaity Modeing for Teachers 25 There are a number of projects that students can do using these onine materias, and we hope that some of you might consider creating a new project that incorporates these materias. In the next set of sides, we describe four projects, starting with one that uses an onine Java appet deveoped by air quaity modeers in Caifornia. Each of these projects can be done as stand-aone projects, or in sequence for a onger unit. In describing the projects in the next severa sides, we provide the goa of the project, a sampe instructiona strategy, and our best guess as to the duration of the project, based on our experiences and those of others. The Shodor Education Foundation, Inc. 25

26 Sampe Project: Run Smog City Animated simuation, based on actua mode runs, of ozone eves» Heps students to understand various factors, incuding emissions» Non-mathematica/nonquantitative» NOTE: this is a simuation, not a mode Duration: one cass period Air Quaity Modeing for Teachers 26 Smog City ( is a Java-based simuation that is a usefu pre-ekma activity for preparing students to interact with the air quaity mode. Given time constraints, we might suggest the use of this too over the actua onine EPA mode. However, this is a simuation, the options for changes are imited, and students don t reay get a sense of the types of data that go into an actua mode. We tend to be a itte eery of simuations such as these -- whie they do hep the students engage in a number of what if situations, these simuations do not provide some of the teachabe moments that can be generated by the rea McCoy. For exampe, I have been unabe to get this simuation to suggest, as is true in the rea word, that a reduction in primary emissions sometimes resuts in an increase in ozone eves. Regardess, this is a great too to use to hep the student begin to understand that meteoroogy (as represented by temperature, inversions, wind speed, and coud cover) and emissions (as represented by popuation and the four types of emissions sources) are the critica determinants of ozone eves. The Shodor Education Foundation, Inc. 26

27 Sampe Project: Effect of Design Ratio Goa: determine effect of one variabe (design ratio) on the impact of VOC and NOx reduction Strategy: five runs» Design ratio 6 VOCs : 1 NOx 12:1 18:1 24:1 30:1» compare reative impact of VOC versus NOx reduction Duration: one or two cass periods for runs Air Quaity Modeing for Teachers 27 This activity is best done in a team-approach, having each student do one of the runs. In this activity, the students are investigating the effect of different design ratios. The discovery activity is the creation of the graphic shown on Side 16, so you may wish to not show them that graphic if you are using these sides for presenting this activity. Optionay, you can discuss that graphic, then have them do a verification type of activity. What I have done in the past that works we is to pot VOC and NOx reduction percentages using a bar graph in Exce or Appeworks. From that graph it s pretty easy to see which primary poutant is the best one to change for a given design ratio. Probaby the best resuts are shown starting with a daiy design vaue of 0.16 ppm in a summertime environment, but you can experiment with various scenarios. The Shodor Education Foundation, Inc. 27

28 Sampe Project: Contro Strategy Design Goa: given a design ratio, design a baanced contro strategy Too: OZIP, using the EKMA approach Strategy: mutipe runs» Form groups of students» Each group investigate one fixed NOx percentage reduction (I.e. 10%, 20%, etc.)» Incude CO reduction to investigate its effect» Once decided, does the contro strategy work in different seasons in different ocations? Duration: short project, but can take severa days to severa weeks, depending on number of runs Air Quaity Modeing for Teachers 28 Given a itte more time, another project is to have students, preferaby working in groups, expore different contro strategies. Hopefuy they wi have seen, verified, and/or discovered the contro strategies guideine chart shown on Side 16, and wi use that to determine some starting points for their contro strategy. For exampe, you might have one group of students be the 10% NOx group, where they set NOx reduction at a fixed vaue, then et the mode expore different vaues of VOCs. Additionay, they might wish to see if CO (carbon monoxide) has an effect on the overa contro strategy, and if so, what that effect might be. Once the students sette on a contro strategy that they think works, they might want to try to appy that contro strategy to different times of the year at different ocations in the United States. They shoud not try to run the mode for ocations outside of the US, the photochemica parameters are set for North America. The Shodor Education Foundation, Inc. 28

29 Sampe Project: Using the Fu Scenario Goa: use the fu scenario as described on the eft side of the main web page Too: requires use of advanced version of the interface Strategy: teams of five students» Each student has a roe: computer modeer, chemist, meteoroogist, emissions inventory speciaist, pubic poicy speciaist» Task: prepare a technica memo for the CEO of LotsoNOx, Inc. regarding his/her options, with cost amounts, for reducing emissions from his coa-burning pant to reach compiance Duration: severa weeks Air Quaity Modeing for Teachers 29 We have had severa universities and high schoos participate in the fu scenario as described in the Scenario section on the main Web page. In this scenario, students form a consuting company that is contracted to provide a recommendation to the CEO of a arge poution-producing company. The students are asked to deiver a technica memo to the CEO that describes a contro strategy that wi hep the CEO to ensure that the community surrounding his/her pant is in compiance with federa air quaity standards. The students are provided $1 miion to work with, that is, the cost of their recommended reductions must not exceed that amount. Approximate costs for each percentage reduction of each of the three primary poutants are provided in the scenario materias. This is a engthy activity. We have worked with severa high schoos that have used this with great success in AP Environmenta Science casses over a period of severa weeks to a month (not, of course, to the excusion of other activities). In a of these groups, Shodor has served as onine consutants, providing technica support and paying the roe of EPA program officer, offering ega and technica opinions. Note that the fu scenario requires the use of the advanced interface, not described in this presentation! The Shodor Education Foundation, Inc. 29

30 Technica Notes Run times:» Typica run times: 3-8 minutes, depending on oad Advising Shodor prior to runs» Notifications are hepfu Onine, rea-time technica hep runaway jobs System debugging Air Quaity Modeing for Teachers 30 We concude this presentation with some technica notes. In designing your instructiona program, you shoud know that each run can take three to eight minutes, onger if mutipe students are doing runs. You need to remember that this mode is numericay-intensive. Even running on a reasonaby powerfu scientific workstation, there are a ot of cacuations to be done. Students need to work together to ensure that ots of them are not submitting jobs at the same time! Towards that end, it s hepfu if you, as the instructor, et us know a day or two ahead of time that your students wi be doing runs. We can hep by monitoring the system, making sure that runaway jobs are kied, and generay keep track of how things are doing and provide advice back to you and/or the students. Given an appropriate amount of ead time, we can aso work directy with your students through onine chats or videoconferencing as they work their way through the mode. We strongy recommend this if students are doing the fu scenario! Thanks for taking the time to work through this presentation, and hope to see you a onine January 30! The Shodor Education Foundation, Inc. 30