Using OMI NO2 and CAMx simulations to estimate emissions from point and area sources

Benjamin de Foy, Saint Louis UniversityNASA Air Quality Applied Sciences Team 6th Meeting

15-17 January 2014, Rice University

Estimation of direct emissions and atmospheric processing of reactive mercury using inverse modeling

B. de Foy, J.B. Heo, J. J. Schauer, Atmospheric Environment, 2014

Least-Squares Inversion combines Back-trajectories, Forward Dispersion from Forest Fires and the Free Troposphere,

Chemical Tracers and a Chemical Box Model

Test Emissions Estimates usingWRF & CAMx simulations

Domain 1, 27km cell size Domain 2, 9km cell size

Year-long WRF simulations for 2005

Emissions Estimation Methods:Box Model / Gaussian Fit / Exponentially-

Modified Gaussian Fit

Duncan, B. N., Yoshida, Y., de Foy, B., Lamsal, L. N., Streets, D. G., Lu, Z., & Krotkov, N. A. (2013). The observed response of Ozone Monitoring Instrument (OMI) NO2 columns to NOx emission controls on power plants in the United States: 2005–2011. Atmospheric Environment.“Introduction to Atmospheric Chemistry”, Daniel Jacob

Emissions Estimation Methods:Box Model / Gaussian Fit / Exponentially-

Modified Gaussian Fit

Lu, Zifeng, et al. "OMI Observations of Interannual Increase in SO2 Emissions from Indian Coal-Fired Power Plants during 2005− 2012." Environmental science & technology (2013).Fioletov, V. E., et al. "Estimation of SO2 emissions using OMI retrievals." Geophysical Research Letters 38.21 (2011).

Emissions Estimation Methods:Box Model / Gaussian Fit / Exponentially-

Modified Gaussian Fit

Beirle, S., Boersma, K. F., Platt, U., Lawrence, M. G., & Wagner, T. (2011). Megacity emissions and lifetimes of nitrogen oxides probed from space. Science, 333(6050), 1737-1739.Valin, L. C., Russell, A. R., & Cohen, R. C. (2013). Variations of OH radical in an urban plume inferred from NO2 column measurements. Geophysical Research Letters.

Simulation Test Cases: No ChemistryEastward PlumesUniform Plume Directions

Idealized Winds:5m/s from the West(31 days)

WRF Winds for 2005(365 days)

Simulation Test Cases: 1 hr Chemical LifetimeEastward PlumesUniform Plume Directions

Idealized Winds:5m/s from the West(31 days)

WRF Winds for 2005(365 days)

Emissions Estimation Methods: Box Model

Input Box ModelIdeal WRF

Emissions (kton/year)No Chemistry 47.0 44.2 33.912-hr Chemistry 47.0 39.5 23.71-hr Chemistry 47.0 14.7 5.0Wind Speed (m/s) 5 0 - 2.5

Average plume for 2005interpolated to 2km gridwith box used for estimation

Emissions Estimation Methods:Gaussian Fit

Average of 2005 Plume 2D Gaussian Fit

Emissions Estimation Methods:Gaussian Fit

Input Box Model Gaussian FitIdeal WRF Ideal WRF

Emissions (kton/year)No Chemistry 47.0 44.2 33.9 47.9 55.512-hr Chemistry 47.0 39.5 23.7 48.2 49.31-hr Chemistry 47.0 14.7 5.0 36.4 22.6Wind Speed (m/s) 5 0 - 2.5 5 0 - 2.5Plume Direction Eastward Uniform Uniform UniformLifetime (hr)No Chemistry Infinity 0.9 1.912-hr Chemistry 12 0.9 1.71-hr Chemistry 1 0.7 1.3

Emissions Estimation Methods:Exponentially-Modified Gaussian Fit

1-hr Chemical Lifetime, WRF Winds, Eastward Plume

No Chemistry, WRF Winds, Eastward Plume

1D plot of the sum along the y-axis of the rotated plume

Emissions Estimation Methods:Exponentially-Modified Gaussian Fit

Input Box Model Gaussian Fit EMG FitIdeal WRF Ideal WRF Ideal WRF

Emissions (kton/year)No Chemistry 47.0 44.2 33.9 47.9 55.5 46.7 48.012-hr Chemistry 47.0 39.5 23.7 48.2 49.3 46.7 46.21-hr Chemistry 47.0 14.7 5.0 36.4 22.6 46.1 40.1Wind Speed (m/s) 5 0 - 2.5 5 0 - 2.5 5 5 - 10Plume Direction Eastward Uniform Uniform Uniform Eastward EastwardLifetime (hr)No Chemistry Infinity 0.9 1.9 425 400012-hr Chemistry 12 0.9 1.7 11.4 10.21-hr Chemistry 1 0.7 1.3 1.0 1.1

Conclusions: Using OMI NO2 and CAMx simulations to estimate emissions from point and area sources

Box Model Gaussian Fit EMG FitEmissions Estimate: Linear dependence on plume speed estimate

Plume Speeds: Robust Weak Winds Stronger Winds

Plume Direction: Robust Uniform Dispersion

Accurate Plume Rotation

Chemistry: Sensitive Fairly Robust Robust

Lifetime Estimate: Input to model based on plume speed and box

size

Dispersion, very short

Chemical, biased low

Benjamin de Foy, Saint Louis University