Timothy Logan

Timothy Logan

Assistant Professor

Director of the Houston Lightning Mapping Array (HLMA) Network

Aerosol-cloud Interactions, Aerosol Chemistry, Biomass Burning Smoke, Atmospheric Electricity


  (979) 845-2004

  Eller O&M 1009A


My current research consists of the following funded projects:

(1) Aerosol impacts on lightning and severe weather in the Houston Metropolitan Area. The NSF funded Experiment of Sea Breeze Convection, Aerosols, Precipitation and Environment (ESCAPE) project (2020-2023) employs the Houston Lightning Mapping Array (HLMA) to analyze lightning behavior within the confines of a larger multi-platform and interdisciplinary field campaign, the Tracking Aerosol Convection Interactions Experiment (TRACER).

(2) Aerosol transport and impacts on low-level cloud development over land and ocean which is funded by two NSF Collaborative Research Grants (2017-2020 and 2020-2023). Research involves using surface-based Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) retrievals, aircraft in situ measurements, and NASA Modern Era Retrospective Reanalysis for Research (MERRA-2) data. There is a specific interest in investigating aerosols derived from biomass burning.

(3) Texas A&M University Tier One Proposal (TOPS) grant (2018-2021) to analyze aerosol transport and aerosol impacts on boundary layer clouds using a portable mini-micropulse LIDAR (MPL). The MPL has captured several Saharan dust intrusions over the Bryan/College Station area as well as smoke/pollution emissions from local and long-range transport sources. During May 2019, the MPL was part of a two week field excursion where it sampled boundary layer aerosols during several instances of deep convection in the Southern Great Plains regions. The McCook, Nebraska tornado was thoroughly sampled including the bounded weak echo region (BWER) and TVS just before the tornado was observed.

(4) NOAA Grant (2017-2019) to validate the Geostationary Lightning Mapper sensor data using the Houston Lightning Mapping Array (HLMA). Current projects include impacts of Hurricane Harvey, Hurricane Barry, and other catastrophic flooding events in and around the Houston Metropolitan and Bryan/College Station Micropolitan areas.

Future research will incorporate laser spectroscopy to investigate the physical and radiative properties of aerosols such as mineral dust and ash/soot that are derived from local and long-range transport sources. In addition, there are future plans to expand coverage of the Houston Lightning Mapping Array to investigate the impacts of marine and tropical convection on communities and business interests along the Texas Gulf Coast as well as over remote areas of the Gulf of Mexico.

My primary research goals are (1) investigate the relationship between lightning source/flash rates and precipitation/flooding events in the Houston Metropolitan Area and communities along the Texas Gulf Coast, (2) analyze the long-term aerosol impacts on low-level and deep convective cloud development, and (3) discern the possible impacts of biomass burning smoke aerosols on severe weather and lightning.


The HLMA provides a service to the surrounding community by providing timely and reliable lightning data to make informed decisions in regards to public safety interests while providing quality data for collaborative, interdisciplinary research within the university community and for K-12 STEM projects.

Selected Publications

Logan, T., B. Xi, X. Dong, R. Obrecht, Z. Li, and M. Cribb (2010), A Study of Asian Dust Plumes Using Satellite, Surface, and Aircraft Measurements during the INTEX-B Field Experiment, J. Geophy. Res., 115, D00K25, doi:10.1029/2010JD014134.

Logan, T., B. Xi, X. Dong, Z. Li, and M. Cribb (2013), Classification and Investigation of Asian Aerosol Properties, Atmos. Chem. Phys., 13, 2253-2265, www.atmos-chem-phys.net/13/2253/2013/doi:10.5194/acp-13-2253-2013.

Logan, T., B. Xi, and X. Dong (2013), A Comparison of the Mineral Dust Absorptive Properties from Two Asian Dust Events, Atmosphere, 4(1), 1-16; doi:10.3390/atmos4010001.

Logan, T., B. Xi, and X. Dong (2013), Biomass Burning Aerosol Properties over the Northern Great Plains during the 2012 Warm Season, Atmos. Chem. Phys. Discuss., 13, 32269–32289, www.atmos-chem-phys-discuss.net/13/32269/2013/doi:10.5194/acpd-13-32269-2013.

Mao, F., W. Gong, and T. Logan (2013), Linear Segmentation Algorithm for Detecting Layer Boundary with LIDAR, Optics Express, 21(22), doi:10.1364/oe.21.026876.

Logan, T., B. Xi, and X. Dong (2014), Aerosol properties and their influences on marine boundary layer cloud condensation nuclei at the ARM mobile facility over the Azores, J. Geophys. Res., 119, doi:10.1002/2013JD021288.

Wang W., L. Sheng, X. Dong, W. Qu, J. Sun, H. Jin, and T. Logan (2016), Dust aerosol impact on the retrieval of cloud top height from satellite observations of CALIPSO, CloudSat and MODIS. J. Quant. Spectrosc. Radiat. Transfer, http://dx.doi.org/10.1016/j.jqsrt.2016.03.034.

Tian P., X. Cao, L. Zhang, N. Sun, L. Sun, T. Logan, J. Shi, Y. Wang, Y. Ji, Y. Lin, Z. Huang, T. Zhou, Y. Shi, and R. Zhang (2017), Seasonal and spatial variations in aerosol vertical distribution and optical properties over China from long-term satellite and ground-based remote sensing. Atmos. Chem. Phys., 17, 2509-2523, http://www.atmos-chem-phys.net/17/2509/2017/doi:10.5194/acp-17-2509-2017.

Logan, T., X. Dong, and B. Xi (2018), Aerosol properties and their impacts on surface CCN at the ARM Southern Great Plains site during the 2011 Midlatitude Continental Convective Clouds Experiment. Adv. Atmos. Sci., 35(2), 224–233, https://doi.org/10.1007/s00376-017-7033-2.

Logan, T. (2018), Anomalous Lightning Behavior during the 26-27 August 2007 Northern Great Plains Severe Weather Event. J. Geophys. Res. Atmos., 123, https://doi.org/10.1002/2017JD027750.

Li, R., G. Tang, J. Ding, T. Logan, S. D. Brooks, D. R. Collins, P. Yang and G. W. Kattawar (2018), Laboratory measurements of light scattering properties of kaolinite dust at 532 nm, Aerosol Sci. Tech., doi:10.1080/02786826.2018.1444729, 1-13.

Bowen P., Y. Wang, J. Hu, Y. Lin, J.-S. Hsieh, T. Logan, X. Feng, J. H. Jiang, Y. Yung, and R. Zhang, (2018), Impacts of Saharan Dust on Regional Climate and Tropical Cyclogenesis over the Atlantic, J. Clim., https://doi.org/10.1175/JCLI-D-16-0776.1.

Pan Z., F. Mao, W. Wang, T. Logan, J. Hong (2018), Examining Intrinsic Aerosol-Cloud Interactions in South Asia through Multiple Satellite Observations, J. Geophys. Res. Atmos., 123, https://doi.org/10.1029/2017JD028232, 1-15.

Zhang, Y., J. Fan, T. Logan, Z. Li, and C. R. Homeyer (2019), Wildfire impact on environmental thermodynamics and severe convective storms, Geophys. Res. Lett., 46. https://doi.org/10.1029/2019GL084534

Zheng, X., B. Xi, X. Dong, T. Logan, Y. Wang, and P. Wu (2020). Investigation of Aerosol-Cloud Interactions under Different Absorptive Aerosol Regimes using ARM SGP Ground-Based Measurements, Atmos. Chem. Phys., 20, https://doi.org/10.5194/acp-20-3483-2020, 3483-3501.

Logan, T., X. Dong, B. Xi, X. Zheng, P. Wu, Y. Wang, *E. Marlow, and *J. W. Maddux (2020), Quantifying the seasonal climatological trends and impacts of aerosols in North America using a novel aerosol component classification index, accepted to Journal of Earth and Space Sciences. *Undergraduate Independent Research Students

Wang, Y., X. Zheng, X. Dong, B. Xi, P. Wu, T. Logan, and Y. Yung (2020), Long-range Transport of Aerosols on Marine Boundary Clouds in the Eastern North Atlantic, under review Atmospheric Chemistry and Physics/Atmospheric Measurement and Technologies Special Issue – Marine aerosols, trace gases, and clouds over the North Atlantic.

Logan, T. (2020), An analysis of the performance of the Houston Lightning Mapping Array during an intense period of convection during Tropical Storm Harvey, under review Journal of Geophysical Research Special Issue: The Three Major Hurricanes of 2017: Harvey, Irma, and Maria.







2015: TAMU Atmospheric Science Department Outstanding Faculty Teaching Award

2015: Hubei Province, China Scientific Paper Award “Mao, F., W. Gong, and T. Logan (2013), Linear Segmentation Algorithm for Detecting Layer Boundary with LIDAR, Optics Express, 21(22), doi:10.1364/oe.21.026876.”

2014: American Meteorological Society Best Student Poster Award

2011: National Science Foundation East Asian and Pacific Summer Institutes (EAPSI) in China Fellowship

2009: North Dakota Space Grant Consortium Fellowship


ATMO 201 – Weather and Climate – introductory meteorology class
ATMO 291/491 – Independent Undergraduate Research – processing HLMA and MPL data; students present findings at national conferences (e.g., AMS and AGU)
GEOS 101 – First Year Experience (Hullabaloo U): Science Can Be A Real Disaster
GEOS 681 – Graduate Seminar

Update My Profile