M. Talat Odman, Yongtao Hu and Armistead G. Russell School of Civil and Environmental Engineering Georgia Institute of Technology

Transcription

1 M. Talat Odman, Yongtao Hu and Armistead G. Russell School of Civil and Environmental Engineering Georgia Institute of Technology AQAST 10 at EPA Research Triangle Park, NC January 5, 2016

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3 Prescribed burning (PB) is practiced to improve native vegetation and wildlife habitat, control insects and disease, and reduce wildfire risk. Georgia Fort Benning, Georgia 23/01/2009 US EPA 2011 National Emission Inventory reported that 15% of PM2.5 emissions in the USA (840 Gg) are attributable to PB.

4 Since 2006 we are forecasting air quality in Georgia. As of November 2014, we started forecasting the individual air quality impacts of three emission sources: 1) power plants, 2) vehicular traffic, and 3) prescribed burning. We use the Decoupled Direct Method (DDM) available in Community Multiscale Air Quality (CMAQ ) model Version to calculate the source impacts. We use special techniques to provide accurate emissions inputs to our forecasts, including a new weather-based prescribed burn forecasting system that mines a burn permit database for geographic burning patterns. We also use surface and satellite observations along with simulated concentrations and their sensitivities to emissions in an inverse modeling framework to continuously adjust anthropogenic emissions.

5 The model was trained with meteorological data at 18 fire weather stations in Georgia and burn permit data for each county. The weather forecast is used to predict if tomorrow will be a burn day in any county Burn Forecast Evaluation: F1 Score 5

6 Typical burn sizes are assigned according to the dominant burner type in the county (institutional, commercial or small) and burns totaling to the county-average daily burn area are randomly distributed to managed lands. Burn emissions are estimated for forecasted burns using: o o o Fuel Characteristic Classification System (FCCS) fuelbed maps for fuel loads, Fuel moisture forecasts for fuel consumption, and Emission factors for Southeast USA fuels. Burn emissions are distributed to the vertical layers of the CMAQ model based on plume rise calculations. 6

7 We compare our forecast quantitatively to: Burn areas provided by NOAA s Biomass Burning Emission Product for North America blended from GOES-E, GOES-W, MODIS, and AVHRR. Burn areas permitted by the Georgia Forestry Commission Satellite burn areas are 5-6 times smaller than permitted burn areas.

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9 Slope = 0.33 R2 = 0.54 Slope = 0.17 R2 = 0.45

10 Slope = 0.02 R2 = 0.33 Slope = 0.21 R2 = 0.50

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12 w/o Burns Forecasts for February 7, 2015 with Burns Burn Impacts (magnified) O3 PM2.5

13 In places where air quality is already stressed by anthropogenic emissions, PB emissions can lead to major health and environmental problems by: Increasing the levels of primary pollutants, and Enhancing the formation of secondary pollutants. When PB emissions coexist with emissions from other sources such as power plants and vehicular traffic, complex chemical interactions take place between them. In Southeastern US, where prescribed burning is routinely practiced both for maintaining ecosystem health and reducing wildfire risk, smoke plumes from prescribed fires frequently encroach urban areas where there is an abundance of anthropogenic emissions. 13

14 Impacts on PM2.5 (µg/m 3 ) Power Plant Impacts w/o Burns Power Interaction Plant Impacts vs. P. Plant with Impact Burns Burn Impacts Plant Burn Interactions

15 Power Plant Burn Interactions PM 2.5 NO 3

16 Impacts on PM2.5 (µg/m 3 ) Traffic Impacts w/o Burns Traffic Interaction Impacts vs. Traffic with Impact Burns Burn Impacts Traffic Burn Interactions

17 Traffic Burn Interactions PM 2.5 NO 3

18 Low-intensity understory burns are not captured well by the satellites. This may be due to the interference of the canopy. Using our forecasting system, we simulated the impacts of power plants and on-road vehicles on O 3 and PM2.5 concentrations with and without the burn emissions. We attributed the difference between the two sets of simulated impacts to the interactions between the wildland fires and anthropogenic emissions. Results for periods of large prescribed burn impacts in urban areas during the 2015 burning season provided a first estimate on the levels of potential interactions. 18

19 NASA Air Quality Applied Sciences Team) RD US EPA Georgia Environmental Protection Division Georgia Forestry Commission

20 Impacts on O3 (ppb) Power Plant Impacts w/o Burns Power Interaction Plant Impacts vs. P. Plant with Impact Burns Burn Impacts Plant Burn Interactions

21 Impacts on O3 (ppb) Traffic Impacts w/o Burns Traffic Interaction Impacts vs. Traffic with Impact Burns Burn Impacts Traffic Burn Interactions