Algorithm Development

Emission estimates of nitrogen oxides, sulfur dioxide, and carbon monoxide are essential for understanding air pollution caused by human activities and for developing effective air quality regulations. We use remote sensing observations with data assimilation and inverse modeling techniques to provide an independent alternative to bottom-up emission estimates, which offers the advantage of comprehensive spatial coverage and the potential for near-real-time production. We also developed new data assimilation frameworks to account for chemical interactions and estimate activity rates and species emission factors using remote sensing data.

Related Publications

  • Qu, Z., D. K. Henze, H. Worden, Z. Jiang, B. Gaubert, N. Theys, and W. Wang, Sector-based top-down estimates of NOx, SO2, and CO emissions in East Asia, Geophys. Res. Lett., 49, e2021GL096009, doi: 10.1029/2021GL096009, 2022.

 

  • Qu, Z., D. K. Henze, O. R. Cooper, and J. L. Neu, Impacts of global NOx inversion on NO2 and ozone simulations, Atmos. Chem. Phys., 20, 13109-13130, doi:10.5194/acp-20-13109-2020, 2020.

 

  • Elguindi, N., C. Granier, T. Stavrakou, S. Darras, M. Bauwens, H. Cao, C. Chen, H.A.C. Denier van der Gon, O. Dubovik, T. M. Fu, D. K. Henze, Z. Jiang, S. Keita, J. J. P. Kuenen, J. Kurokawa, C. Liousse, K. Miyazaki, J. F. Muller, Z. Qu, F. Solmon, and B. Zheng, Intercomparison of magnitudes and trends in anthropogenic surface emissions from bottom-up inventories, top-down estimates, and emission scenarios, Earths Future, doi:10.1029/2020EF001520, 2020.

 

  • Wang, Y., J. Wang, X. Xu, D. K. Henze, Z. Qu, and K. Yang, Inverse modeling of SO2 and NOx emissions over China using multi-sensor satellite data – Part 1: Formulation and sensitivity analysis, Atmos. Chem. Phys., doi:10.5194/acp-20 6631-2020, 2020.

 

  • Qu, Z., D. K. Henze, C. Li, N. Theys, Y. Wang, J. Wang, W. Wang, J. Han, C. Shim, R. R. Dickerson, and X. Ren, SO2 emission estimates using OMI SO2 retrievals for 2005-2017, J. Geophys. Res. – Atmos., 124, 8336–8359, doi:10.1029/2019JD030243, 2019.

 

  • Qu, Z., D. K. Henze, N. Theys, J. Wang, and W. Wang, Hybrid mass balance / 4D-Var joint inversion of NOx and SO2 emissions in East Asia, J. Geophys. Res. – Atmos., 124, 8203–8224, doi: 10.1029/2018JD030240, 2019.

 

  • Jiang, Z., B. C. McDonald, H. Worden, J. R. Worden, K. Miyazaki, Z. Qu, D. K. Henze, D. B. A. Jones, A. F. Arellano, E. V. Fischer, L. Zhu, and F. K. Boersma, Unexpected slowdown of US pollutant emission reduction in the past decade, Proc. Natl. Acad. Sci., 115(20), 5099-5104, doi:10.1073/pnas.1801191115, 2018.

 

  • Qu, Z., D. K. Henze, S. L. Capps, Y. Wang, X. Xu, J. Wang, and M. Keller, Monthly top-down NOx emissions for China (2005-2012): A hybrid inversion method and trend analysis, J. Geophys. Res. – Atmos., 122, 4600–4625, doi:10.1002/2016JD025852, 2017.

 

  • Wang, Y., J. Wang, X. Xu, D. K. Henze, Y. Wang, and Z. Qu, A new approach for monthly updates of anthropogenic sulfur dioxide emissions from space: Application to China and implications for air quality forecasts, Geophys. Res. Lett., 43, 9931-9938 doi:10.1002/2016GL070204, 2016.