Andrew Gray is an Associate Professor of Watershed Hydrology at the University of California, Riverside where he leads a research group focused on sediment transport from watersheds to coastal marine environments.

Andrew’s research ranges from post-fire sediment transfer processes in headwater systems, to fluvial suspended sediment dynamics, and coastal geomorphology. His current research is heavily focused on microplastic source, transport, and fate across the watershed to coastal marine continuum.

Hapich H, Cowger W, Gray A. 2024. Microplastics and Trash Cleaning and Harmonization (MaTCH): Semantic Data Ingestion and Harmonization Using Artificial Intelligence (AI). Environmental Science and Technology. in press.

Karapetrova A, Cowger W, Michell A, Braun A, Bair E, Gray A, Gan J. 2024. Microplastic Distribution in Western North American Snow. Journal of Hazardous Material. 480: 136126. https://doi.org/10.1016/j.jhazmat.2024.136126.

Cowger W, Markley LAT, Moore, S, Gray AB, Upadhyay K, Koelmans AA. 2024. How many microplastics do you need to (sub)sample. Ecotoxicology and Environmental Safety. 275(15): 116243. https://doi.org/10.1016/j.ecoenv.2024.116243.

Guilinger JJ, Foufoula-Georgiou E, Gray AB, Randerson J, Smyth P, Barth N, Goulden M. 2023. Predicting postfire sediment yields of small steep catchments using airborne lidar differencing. Geophysical Research Letters. 50: e2023GL104626. https://doi.org/10.1029/2023GL104626.

Cowger W, Gray A, Brownlee S, Hapich H, Deshpande A, Waldschlager K. 2022. Estimating floating macroplastic flux in the Santa Ana River, California. Journal of Hydrology: Regional Studies. 44: 101264. https://doi.org/10.1016/j.ejrh.2022.101264.

Jumps N, Gray AB, Guilinger JJ, Cowger WC. 2022. Wildfire Impacts on the Persistent Suspended Sediment Dynamics of the Ventura River, California. Journal of Hydrology: Regional Studies. 41: 101096. https://doi.org/10.1016/j.ejrh.2022.101096.

Hapich H, Cowger W, Gray A, Tangri N, Hale T, Magdy A, Vermilye A, Yu W, Ayres D, Moore C, Vermilye J, Haiman ANK, Youngblood K, Kang Y, McCauley M, Lok T, Moore S, Baggs E, Lippiatt S, Kohler P, Conley G, Taing J, Mock J. 2022. Trash Taxonomy Tool: Harmonizing Classification Systems Used to Describe Trash in the Environment. Microplastics & Nanoplastics. 2: 15. https://doi.org/10.1186/s43591-022-00035-1.

Cowger WC, Gray A, Hapich H, Osei-Enin J, Olguin S, Jr., Huynh B, Nogi H, Singh S, Brownlee S, Fong J, Lok T, Singer G, Ajami H. 2022. Litter origins, accumulation rates, and hierarchical composition on urban roadsides of the Inland Empire, California. Environmental Research Letters. 17: 015007. https://doi.org/10.1088/1748-9326/ac3c6a.

Krause J, Hinojosa-Corona A, Gray A, Herguera JC, McDonnell J, Schaefer M, Ying S, Watson E. 2022. Beyond habitat boundaries: organic matter cycling requires a system-wide approach for accurate blue carbon accounting. Limnology and Oceanography. 67(2): S6-S18. https://doi.org/10.1002/lno.12071.

Cowger W, Steinmetz Z, Gray A, Munno K, Lynch J, Hapich H, Primpke S, De Frond H, Rochman C, Herodotou O. 2021. Microplastic Spectral Classification Needs an Open Source Community: Open Specy to the Rescue! Analytical Chemistry. 93(21): 7543-7548. https://doi.org/10.1021/acs.analchem.1c00123.

Cowger W, Gray AB, Guilinger JJ, Fong B, Waldschläger K. 2021. Concentration Depth Profiles of Microplastic Particles in River Flow and Implications for Surface Sampling. Environmental Science and Technology. 55: 6032-6041. https://doi.org/10.1021/acs.est.1c01768.

Guilinger J, Gray A, Barth N, Fong B. 2020. The evolution of sediment sources over a sequence of post-fire sediment-laden flows revealed through repeat high-resolution change detection. Journal of Geophysical Research – Earth Surface. 125: e2020JF005527. https://doi.org/10.1029/2020JF005527.