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Air Quality Modeling. Trends in Urban Asia Sulfur Pollution Model Overview. RAINS-Asia Developed by IIASA, Austria SO 2 , PM, NO x Energy, Emissions, Controls, Costs and Optimization modules. ATMOS Dispersion Model SO 2 , PM, NO x Lagrangian Puff Transport Linear Chemistry
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Trends in Urban Asia Sulfur PollutionModel Overview RAINS-Asia Developed by IIASA, Austria SO2, PM, NOx Energy, Emissions, Controls, Costs and Optimization modules ATMOS Dispersion Model SO2, PM, NOx Lagrangian Puff Transport Linear Chemistry NCEP Winds (1975-2000)
Model OverviewRegional Transport Model: STEM STEM • Structure: Modular (on-line and off-line mode) • Meteorology: RAMS - MM5 - ECMWF - NCEP • Emissions: Anthropogenic, biogenic and natural • Chemical mechanism: SAPRC’99 (Carter,2000) • 93 Species, 225 reactions, explicit VOC treatment • Photolysis: NCAR-TUV 4.1 (30 reactions) • Resolution: Flexible 80km x 80km for regional and 16km x 16km for urban
For Southeast Asia and Indian Sub-Continent Original Fire Count(FC) data(AVHRR) 5-day Fire Count Moving Averaged Fire Count data (Level 2) “Fill-up” Zero Fire Counts using Moving Average(MA) Satellite Coverage Cloudiness Precipitation(NCEP) “Fill-up” Zero Fire Count using TOMS AI Mask Grid (Landcover) Mask Grid (Never Fire) “Extinguish” Fire Count using Mask Grids AI Adjusted Fire Count data (Level 3) Regress. Coeff.(AI/FC) Regional Emission Estimates:Biomass Burning Emissions
Consequences of urban fossil fuel use:Local to Global air pollution Bangkok Visibility Index Impact of Asian NOx Emissions on Global Air Quality % contribution by Asian NOx to total ozone concentrations (2 km) Source: Climatology Division, meteorology department, Thailand Source: Yienger, et al., 2000
Cities: A part of the ProblemEnergy Demand and Pollution Urban Energy Demand Energy Production Waste Management Rising GHG levels Urban transportation
Integrated AssessmentEmissions to End Points Mobile Sources Ozone NOx, VOC, Toxics PM (Cars, trucks, airplanes, boats, etc.) Industrial Sources Acid Rain Chemistry Meteorology Visibility NOx, VOC, SOx, Toxics (Power plants, factories, refineries/chemical plants, etc.) Air Toxics Area Sources Atmospheric Deposition NOx, VOC, Toxics (Homes, small business, farming equipment, etc.)
Regional Emission Estimates:Anthropogenic Sources Industrial and Power Sector Coal, Fuel Oil, NG SO2, NOx, VOC, and Toxics Domestic Sector Coal, Biofuels, NG/LPG SO2, CO, and VOC Transportation Sector Gasoline, Diesel, CNG/LPG NOx, and VOC
Regional Emission Estimates:Natural Sources Biomass Burning In-field and Out-field combustion CO, NOx, VOC, and SPM Volcanoes SO2, and SPM Dust Outbreaks SPM
Regional Emission Estimates:Sectoral Contributions Annual Asian Emissions for Year 2000 PP = Power Sector BB = Biomass Burning IND = Industries TRAN = transport DOM = Domestic SO2 = 34.8 Tg NOx = 25.6 Tg CO = 244.8 Tg VOC = 52.7 Tg SO2 NOx CO VOC
Regional Emission Estimates:% by Economic Sector : SO2 Emissions Domestic Industrial Transport Power
Regional Emission Estimates:% by Economic Sector : NOx Emissions Domestic Industrial Transport Power
For Southeast Asia and Indian Sub-Continent Original Fire Count(FC) data(AVHRR) 5-day Fire Count Moving Averaged Fire Count data (Level 2) “Fill-up” Zero Fire Counts using Moving Average(MA) Satellite Coverage Cloudiness Precipitation(NCEP) “Fill-up” Zero Fire Count using TOMS AI Mask Grid (Landcover) Mask Grid (Never Fire) “Extinguish” Fire Count using Mask Grids AI Adjusted Fire Count data (Level 3) Regress. Coeff.(AI/FC) Regional Emission Estimates:Biomass Burning Emissions
Urban Contribution to Regional PhotochemistryRegional Impact Analysis: STEM • Structure: Modular (on-line and off-line mode) • Meteorology: RAMS - MM5 - ECMWF - NCEP • Emissions: Anthropogenic, biogenic and natural • Chemical mechanism: SAPRC’99 (Carter,2000) • 93 Species, 225 reactions, explicit VOC treatment • Photolysis: NCAR-TUV 4.1 (30 reactions) • Resolution: Flexible 80km x 80km for regional and 16km x 16km for urban
Urban Contribution to Regional PhotochemistryRegional Impact Analysis: STEM Y. Tang (CGRER), 2002
Characterization of Urban Signalshttp://www.cgrer.uiowa.edu/ACESS/acess_index.htm
Urban Contribution to Regional PhotochemistryRegional Impact Analysis: STEM-TUV Y. Tang (CGRER), 2002
Urban PhotochemistryOH Radical Cycle VOC + OH ---> Orgainic PM PM2.5 SOx [or NOx] + NH3 + OH ---> (NH4)2SO4 [or NH4NO3] Ozone Visibility Fine PM (Nitrate, Sulfate, Organic PM) .OH NOx + VOC + OH + hv ---> O3 Acid Rain Water Quality SO2 + OH ---> H2SO4 NOx + SOx + OH (Lake Acidification, Eutrophication) NO2 + OH ---> HNO3 Air Toxics OH <---> Air Toxics (POPs, Hg(II), etc.)
Urban PhotochemistryNOx-VOC-Ozone Cycle • Organic radical production and photolysis of NO2 • VOC’s and N-species compete for OH radical
Urban PhotochemistryNOx-VOC-Ozone Cycle • In polluted environment, CO contributes to O3 production
Urban PhotochemistryNOx-VOC-Ozone Cycle • HCHO – primary intermediate in VOC-HOx chemistry • Short lived and indicator of primary VOC emissions
Urban PhotochemistryNOx-VOC-Ozone Cycle • Organic radical production and photolysis of NO2 • VOC’s and N-species compete for OH radical • In polluted environment, CO contributes to O3 production • HCHO – primary intermediate in VOC-HOx chemistry • Short lived and indicator of primary VOC emissions
Urban PhotochemistryNOx-VOC-Ozone Cycle Units: ppbv/hr O3 Cycle STEM Box Model Calculations For City of Seoul, O3 Cycle STEM Box Model Calculations For City of Shanghai
Urban PhotochemistryNOx-VOC-Ozone Cycle Units: ppbv/hr O3 Cycle STEM Box Model Calculations Downwind Site from Shanghai O3 Cycle STEM Box Model Calculations Downwind Site from Dhaka
Urban Photochemistry Species to Species Comparison CO Vs VOC: Megacity points from back trajectories • CO produced due to photolysis of HCHO, a short lived intermediate from reactions between VOC and HOx • High O3 and CO concentrations are linked with high VOC concentrations, especially with urban plume age < 1.0 day
Urban Photochemistry NOx-VOC Sensitivity Implications • Ozone production in the urban plumes is VOC limited • Decrease in NOx may actually increase local O3 production • Though at present, NOx is contributing less to local O3 mixing ratios, it is contributing to local NO2 mixing ratios (health criteria pollutant) and to O3 production at downwind sites.
Urban Photochemistry NOx-VOC Sensitivity to O3 Production Less than 2 day old plumes VOC sensitive Model results along the flight path Megacity points from back trajectories Loss(N)/(Loss(N)+Loss(R)) NOx sensitive Model NOx (ppbv) Klienman et al., 2000
Ambient Concentration Exposure Emissions Air Quality Management System Policy Issues Technical Options Environmental Integrated Assessment
32o Shanghai East China Sea Shanghai Province 30o36’ 120o36’ 122o Environmental Integrated Assessment Case Study of Shanghai, China Emissions for 1995 PM10 : 166 ktons PM/year PM2.5 : 68 ktons PM/year Sulfur: 458 ktons SO2/year Population: 19 Million Source: Li and Guttikunda et al., 2002
Shanghai Urban Air Quality Management Emission Estimates Units: Gg/year 1995 2020 BAU
Shanghai Urban Air Quality ManagementAnnual Average PM10 Concentrations Units: mg/m3 PM10 in 1995 2020 BAU
Shanghai Urban Air Quality ManagementHealth Benefit Analysis Dose-response function coefficients Coefficient: % change in endpoint per 10 mg/m3 change in annual PM10 levels Incidence rate: rate of occurrence of an endpoint among the population
Shanghai Urban Air Quality ManagementHealth Benefit Analysis No. of cases avoided
Shanghai Urban Air Quality ManagementHealth Benefit Analysis Units: US$ millions in 1998 dollars Economic Evaluation
Days & Weeks Source Receptor Matrix Seconds Integrated Assessment Modeling System (IAMS) Emissions & Costs Dispersion Modeling Depositions & Concentrations Energy Technology Fuel Sectors Scales Exposure & Impacts
IAMS Model Schematics Atmospheric Dispersion Calculations Emission Sources (PM and SO2) Central Heating Plants Industrial Boilers Domestic Sources Large Point Sources Transportation Sources Transfer Matrix for Area Sources Transfer Matrix for LPS Sources PM and Sulfur Concentrations
IAMS Software Tracks Emission Changes. Tracks Concentration Changes.
IAMS Software Calculates Health Damages for Mortality, Chronic Bronchitis, Hospital Visits, Work Day Losses. Tracks Health Benefits to Costs Ratio.