Forecasting and Forecasting and Disseminating AQI in Disseminating AQI in

DelhiDelhi

Joseph CassmassiJoseph Cassmassi

South Coast Air Quality Management District South Coast Air Quality Management District

U.S.AU.S.A

Program ObjectivesProgram Objectives

• Communicate AQI to public Communicate AQI to public ---- real-time cautionary measuresreal-time cautionary measures---- forecast health statementsforecast health statements

• Short-term control programShort-term control program---- actions based on attained actions based on attained

air qualityair quality---- forecast initiated emissions forecast initiated emissions

reductionsreductions

Delhi ProfileDelhi Profile

• Growing!Growing!

• Approximately 10 million residentsApproximately 10 million residents

• 1,500 squared kilometers1,500 squared kilometers

• Traffic congestionTraffic congestion

• Expanding urbanizationExpanding urbanization

• Expanding industrial outputExpanding industrial output

TerrainTerrain

• Generally flat - Yamuna river valleyGenerally flat - Yamuna river valley

• Great Indian Desert to westGreat Indian Desert to west

• Alwar Hills to the southwestAlwar Hills to the southwest

• Mewat Plain to the southMewat Plain to the south

• Ganges River Valley to the eastGanges River Valley to the east

Pollutant BackgroundPollutant Background

• Pollutants monitored Pollutants monitored ---- particulate matterparticulate matter---- ozoneozone---- sulfur oxides sulfur oxides

(sulfates)(sulfates) ---- carbon monoxidecarbon monoxide---- nitrogen dioxidenitrogen dioxide

• Toxics PollutantsToxics Pollutants• Particulate levels significantParticulate levels significant

Expectations Expectations

• Success of forecasting and reporting AQI Success of forecasting and reporting AQI hinges uponhinges upon

---- reliable telemetryreliable telemetry---- effective communications systemeffective communications system---- relaying the message relaying the message ---- timelinesstimeliness

• Public/School/Industry outreach programs Public/School/Industry outreach programs are necessaryare necessary

Forecasting ExpectationsForecasting Expectations

• Targets:Targets:---- preventive health warningspreventive health warnings---- mandatory emissions reductionsmandatory emissions reductions

• Realistic goals: Realistic goals: -- -- what level of pollution reduction what level of pollution reduction

is achievable?is achievable?-- -- what level of pollution reduction what level of pollution reduction

is acceptable?is acceptable?

Forecast AccuracyForecast Accuracy

• Set realistic goalsSet realistic goals

• Prediction accuracy for categories of AQIPrediction accuracy for categories of AQI---- minimum acceptable accuracyminimum acceptable accuracy

50% 50%---- target accuracy 65% or highertarget accuracy 65% or higher

• Prediction accuracy is dependent upon the Prediction accuracy is dependent upon the number of AQI categories forecastnumber of AQI categories forecast

• Concentration forecast error ~ 10% of Concentration forecast error ~ 10% of maximum observed concentrationmaximum observed concentration

Likely Pollutants to Be Forecast Likely Pollutants to Be Forecast

• Highest Priority:Highest Priority:---- Particulate Matter PM10/PM2.5Particulate Matter PM10/PM2.5

(current levels > 300 (current levels > 300 ug/m3)ug/m3) ---- Carbon MonoxideCarbon Monoxide

---- OzoneOzone

• Lesser PriorityLesser Priority---- Nitrogen dioxideNitrogen dioxide

---- Sulfur DioxideSulfur Dioxide---- SulfatesSulfates

Components of Multi-pollutant Components of Multi-pollutant ForecastingForecasting

• Understanding the ProblemUnderstanding the Problem

• Developing the forecasting toolsDeveloping the forecasting tools

• Communicating the right messageCommunicating the right message

Understanding the ProblemUnderstanding the Problem

• Seasonality of the different pollutantsSeasonality of the different pollutants

• Pollutant specific impact zonesPollutant specific impact zones

• Overlapping impactsOverlapping impacts-- time-- time

-- space-- space

Developing ToolsDeveloping Tools

• Availability of historical dataAvailability of historical data

• Blending forecast requirementsBlending forecast requirements

• Adjusting for trends Developing ToolsAdjusting for trends Developing Tools

AQI Prediction AlgorithmAQI Prediction Algorithm

• Empirical Analysis/Pattern RecognitionEmpirical Analysis/Pattern Recognition---- fewer data requirementsfewer data requirements---- site specific predictionsite specific prediction---- no requirement for emissions no requirement for emissions ---- flexible - requires limited time flexible - requires limited time

• Numerical SimulationNumerical Simulation---- data intensive including emissionsdata intensive including emissions---- not flexiblenot flexible

Modeling TechniquesModeling Techniques

• PersistencePersistence

• Multivariate RegressionMultivariate Regression

• Updated Stratified Multivariate RegressionUpdated Stratified Multivariate Regression

• MOS Linked Multivariate RegressionMOS Linked Multivariate Regression

• Nearest Neighbor Analog Prediction Nearest Neighbor Analog Prediction AlgorithmAlgorithm

Air Quality Data AvailabilityAir Quality Data Availability

• Minimum of 2-3 years of dataMinimum of 2-3 years of data

• GasesGases -- -- hourly datahourly data

• Particulates Particulates -- -- Hi Vol PM10 (6Hi Vol PM10 (6thth – day) – day)---- Real-time PM10 samplingReal-time PM10 sampling

(BAM or TEOM)(BAM or TEOM)• Special studies Special studies

Meteorological Data AvailabilityMeteorological Data Availability

• Vertical temperature structure Vertical temperature structure (soundings and pressure surface analyses)(soundings and pressure surface analyses)

• Winds or surrogate (pressure gradients)Winds or surrogate (pressure gradients)

• Humidity: surface and aloftHumidity: surface and aloft

• Numerical Forecast Model OutputNumerical Forecast Model Output

Daily Operational RequirementsDaily Operational Requirements

Task Time (Hrs)

Analyze air quality & weather 3

Run forecast model & evaluate 1

Disseminate AQI forecast 2

Observe developing air quality &prepare for next day’s forecast

2

Data Routinely Used By ForecastData Routinely Used By Forecast

Man Power/LiaisonsMan Power/Liaisons

• Continuous communication between Continuous communication between monitoring and forecast groupsmonitoring and forecast groups

• Liaison and communication between Liaison and communication between agencies (air quality - meteorology) to agencies (air quality - meteorology) to provide dataprovide data

• Forecasting is a daily job requiring sufficient Forecasting is a daily job requiring sufficient staffstaff

• Liaison to media dissemination Liaison to media dissemination

Forecast/AQI CoverageForecast/AQI Coverage

• Global forecast or AQI message Global forecast or AQI message ---- covers total areacovers total area---- single air quality descriptionsingle air quality description

• Forecast zonesForecast zones---- source areas (notification for source areas (notification for

emissions curtailment actions)emissions curtailment actions)---- receptor areas (area specific air receptor areas (area specific air

quality notification)quality notification)

Source/Receptor Areas (SRA)Source/Receptor Areas (SRA)

Forecast Zones Forecast Zones

Knowledge of Emissions SourcesKnowledge of Emissions Sources

• Which sources contributeWhich sources contribute---- inventoryinventory---- speciation profilesspeciation profiles

• To what reasonable level can a source be To what reasonable level can a source be asked to curtail emissions?asked to curtail emissions?---- processprocess---- technologytechnology

• Monitoring & enforcementMonitoring & enforcement

• ExemptionsExemptions

Burning IssuesBurning Issues

• Control agricultural burningControl agricultural burning-- -- criteria in forecast criteria in forecast ---- smoke management program smoke management program

• Banning open burning of refuse Banning open burning of refuse ---- stagnant meteorological conditionsstagnant meteorological conditions---- seasonallyseasonally

Getting the Message OutGetting the Message Out

SOUTH COAST AIR QUALITY MANAGEMENT DISTRICTSMOG EPISODE NOTIFICATION

WEDNESDAY, MAY 05, 1999

Today’s Air Quality: Valid Wednesday, May 05, 1999Today, May 5, 1999, air quality is expected to be GOOD to MODERATE in most areas,but air pollution levels will exceed the Federal Clean Air Standard of 100 on the PollutantStandard Index (PSI) in the following areas:

Area # Monitoring Area Description Pollutant PSI Time23 Metropolitan Riverside Unhealthful Ozone 113 2 to 5 p.m.34 Central San Bernardino Vly. Unhealthful Ozone 113 2 to 5 p.m.35 East San Bernardino Valley Unhealthful Ozone 113 2 to 5 p.m.37 Central San Bernardino Mtns. Unhealthful Ozone 113 3 to 6 p.m.

Tomorrow’s Forecast: Valid Thursday, May 6, 1999Tomorrow, May 6, 1999, air quality is predicted to be GOOD to MODERATE in mostareas, but air pollution levels will exceed the Federal Clean Air Standard of 100 on thePollutant Standards Index (PSI) in the following areas:

Area # Monitoring Area Description Pollutant PSI Time34 Central San Bernardino Vly. Unhealthful Ozone 113 2 to 5 p.m.35 East San Bernardino Valley Unhealthful Ozone 113 2 to 5 p.m.

What To Do When Air Pollution Exceeds the Federal Clean Air StandardIn areas with UNHEALTHFUL air quality (PSI of 101 to 137), susceptible persons, such as thosewith heart or lung disease, should minimize outdoor activity.

In areas with HEALTH ADVISORY EPISODES for ozone (PSI of 138 to 199), everyone shoulddiscontinue prolonged, vigorous outdoor exercise lasting longer than one hour. Examples of the kindsof outdoor activities that should be avoided are calisthenics, basketball, running, soccer, football,tennis, swimming laps, water polo. Susceptible persons, such as those with heart or lung disease,should avoid outdoor activity entirely.

In areas having STAGE I EPISODES (PSI of 200 or above), everyone should discontinue allvigorous outdoor activities regardless of duration.

Typical Media ForecastTypical Media Forecast

-----------------------------------------------------------------------AIR QUALITY FORECAST*-----------------------------------------------------------------------

ON TUE., MAY. 4, 1999 THE SOUTH COAST AIR QUALITYMANAGEMENT DISTRICT PREDICTS THE AIR QUALITY WILL BE ...

GOOD IN THE: COASTAL AREA, PSI: 42 OZONE METROPOLITAN AREA, PSI: 50 OZONE INLAND ORANGE COUNTY AREAS, PSI: 50 OZONE BIG BEAR LAKE AREAS, PSI: 50 OZONEMODERATE IN THE: SAN FERNANDO/SANTA CLARA VALLEYS, PSI: 58 OZONE SAN GABRIEL/POMONA VALLEYS, PSI: 67 OZONE RIVERSIDE/SAN BERNARDINO AREAS, PSI: 67 OZONE HEMET/ELSINORE AREAS, PSI: 58 OZONE HIGH DESERT, PSI: 67 OZONE LOW DESERT, PSI: 84 PM10 BANNING AREA, PSI: 58 OZONE_______________________________________________________________________

First StepsFirst Steps

• Evaluate ability to develop reliable data Evaluate ability to develop reliable data liaisons: forecasting and reportingliaisons: forecasting and reporting

• Expand the monitoring network to provide Expand the monitoring network to provide enhanced characterization of problemenhanced characterization of problem

• Decide on the scope of the AQI/forecast Decide on the scope of the AQI/forecast message: global or site specificmessage: global or site specific

Second StepsSecond Steps

• Develop basic conceptual modelDevelop basic conceptual model

• Evaluate forecaster’s ability to identify the Evaluate forecaster’s ability to identify the general profilegeneral profile

• Start with a categorical AQI predictionStart with a categorical AQI prediction

• Develop confidence in forecastDevelop confidence in forecast

• Data analysis to develop a simple modelData analysis to develop a simple model

• Develop confidence in model predictionsDevelop confidence in model predictions

AcceptanceAcceptance

• AQI acceptance is tied to its simplicity in AQI acceptance is tied to its simplicity in conveying a messageconveying a message

• AQI forecast needs to reasonably accurateAQI forecast needs to reasonably accurate---- avoid “cry wolf”avoid “cry wolf”

---- capture events if not capture events if not peak peak concentrationsconcentrations

• Industry will usually accept a program that Industry will usually accept a program that is designed to be unbiasedis designed to be unbiased