Biography
I am an M.S. student in the Department of Climate, Meteorology, and Atmospheric Sciences working with Dr. Hannah Horowitz. I'm originally from Madison, WI, and earned a B.S. in Computer Science and Environmental Studies at the University of Wisconsin-Madison in 2024. Outside of research, I enjoy baking, cooking, hiking, and reading.
Research Interests
My research focuses on air quality and public health, specifically how we can use satellite and chemical transport model data to expand monitoring of hazardous pollutants, such as fine particulate matter or nitrogen dioxide, across the United States.
Research Description
In the Horowitz Lab, I am currently studying how monitored, satellite-derived, and GEOS-Chem simulated surface data agrees in three environments that are known to be problematic for fine particulate matter (PM2.5) measurements and modeling. These environments are mountains, deserts, and wildfire risk regions. I am modifying physical processes and emissions within the GEOS-Chem chemical transport model to determine which processes and emissions are most influential to modeled surface PM2.5 in these environments, as well as which contribute to the best and worst agreement among the three PM2.5 datasets. The ultimate goal is to determine which improvements can be made within the model to improve model performance in these environments and give us an idea of how surface PM2.5 may be affected in these region under future, climate-influenced conditions.
Education
- M.S., Atmospheric Science, University of Illinois Urbana-Champaign (expected 2027)
- B.S., Computer Science and Environmental Studies, University of Wisconsin - Madison
Recent Publications
Acker, S., Holloway, T., and Harkey, M. (2025). Satellite detection of NO2 distributions using TROPOMI and TEMPO and comparison with ground-based concentration measurements, Atmos. Chem. Phys., 25, 8271–8288, https://doi.org/10.5194/acp-25-8271-2025
Acker, S., Holloway, T., Stewart, K., van Donkelaar, A., & Martin, R. V. (2026). Comparison of policy‐relevant air quality metrics calculated with sparse in situ monitoring and contiguous satellite‐derived data. GeoHealth, 10, e2025GH001586. https://doi.org/10.1029/2025GH001586
Holloway, T., Acker, S., Kysela, L., Heck, C., van Donkelaar, A., Martin, R. V., et al. (2026). Applying satellite‐derived PM2.5 data to policy‐relevant air quality metrics. GeoHealth, 10, e2025GH001585. https://doi.org/10.1029/2025GH001585
Nawaz, M. O., Huber, D., Kerr, G., Judd, L., Acker, S., Goldberg, D. (2025).
A comparative analysis of TEMPO NO2 remote sensing with surface-level monitoring through diurnal and seasonal trends, meteorology, and monitor characteristics. JGR Atmospheres. https://doi.org/10.1029/2025JD043923
Gesangyangji, G., Holloway, T., Vimont, D. J., Acker, S. J. (2024). Future changes in state-level population-weighted degree days in the U.S. Environmental Research Letters, 19(3), 034029. https://doi.org/10.1088/1748-9326/ad28dd
Gesangyangji, G., Holloway, T., Vimont, D. J., Mastrucci, A., Byers, E., Acker, S. J. (2025). The hours matter: comparing indicators of U.S. residential cooling from hourly versus daily climate variables. Environmental Research Letters. https://doi.org/10.1088/1748-9326/adbd54