Greg Pelletier

Senior Scientist

Greg Pelletier is a Senior Scientist in the Biogeochemistry Department who specializes in numerical modeling of ocean acidification and hypoxia. His research focuses on using models to explain anthropogenic changes in water chemistry and the vulnerability of sensitive marine organisms. He received his M.S.E. in environmental engineering from the University of Washington, and his B.S. in environmental studies from Springfield College (Massachusetts). He is a licensed professional engineer. He joined SCCWRP in 2019 after working for more than 30 years as the lead water quality modeler for the Washington State Department of Ecology.


M.S.E., Environmental Engineering, University of Washington, Seattle, WA, 1985

B.S., Environmental Studies, Springfield College, Springfield, MA, 1979



Professional Experience

Senior Scientist, Southern California Coastal Water Research Project, Costa Mesa, CA. 2019-present

Environmental Engineer, Washington State Department of Ecology, Olympia, WA 1988 - 2019

Environmental Scientist, Harper-Owes, Seattle, WA. 1984-88

Environmental Scientist Intern, Municipality of Metropolitan Seattle, Seattle, WA. 1982-84

Environmental Scientist, Herrera Environmental Consultants, Seattle, WA, 1982-1983

Research Assistant, University of Washington, Department of Civil Engineering, Seattle, WA. 1979-1981



Journal Articles

Nakayama, T. and G. Pelletier. 2018. Impact of global major reservoirs on carbon cycle changes by using an advanced eco-hydrologic and biogeochemical coupling model. Ecological Modelling. Volume 387, 10 November 2018, Pages 172-186.

Khangaonkar T, A Nugraha, W Xu, W Long, L Bianucci, A Ahmed, T Mohamedali, and G Pelletier. 2018. Analysis of Hypoxia and Sensitivity to Nutrient Pollution in Salish Sea. Journal of Geophysical Research – Oceans, 123(7): 4735-4761.

Pelletier G, Roberts M, Keyzers M, Alin SR. 2018. Seasonal variation in aragonite saturation in surface waters of Puget Sound – a pilot study. Elem Sci Anth. 2018;6(1):5. DOI:

Bianucci L, W Long, T Khangaonkar, G Pelletier, A Ahmed, T. Mohamedali, M Roberts, C. Figueroa-Kaminsky. 2018. Sensitivity of the regional ocean acidification and the carbonate system in Puget Sound to ocean and freshwater inputs. Elementa Science of the Anthropocene, 6(1): 22.

Pelletier, GJ, L Bianucci, W Long, T Khangaonkar, T Mohamedali, A Ahmed, and C Figueroa-Kaminsky. 2017. Salish Sea Model, Ocean Acidification Module and the Response to Regional Anthropogenic Sources. Washington State Department of Ecology, Olympia, WA.  Pub. No. 17-03-009;

Pelletier, G., L. Bianucci, W. Long, T. Khangaonkar, T. Mohamedali, A. Ahmed, and C. Figueroa-Kaminsky. 2017. Salish Sea Model: Sediment Diagenesis Module. Washington State Department of Ecology, Olympia, WA.  Pub. No. 17-03-010;

Ahmed, A, G Pelletier, and M Roberts. 2017. South Puget Sound flushing times and residual flows. Estuarine, Coastal, and Shelf Science. 2017, 187, 9-212. DOI:

Sharma, D, A Kansal, and G Pelletier. 2017. Water quality modeling for urban reach of Yamuna river, India (1999–2009), using QUAL2Kw. Appl Water Sci (2017) 7: 1535. DOI:

Cox, TJ, DF Turner, GJ Pelletier, and A Navato. 2015. Stochastic water quality modeling of an impaired river impacted by climate change. ASCE J Env Eng, 141(11).

Hobson, AJ, BT Nielson, N von Stackelberg, M Shupryt, J Ostermiller, G Pelletier, and SC Chapra. 2014. Development of a minimalistic data collection strategy for QUAL2Kw. ASCE J. Water Resour. Plann. Manage. DOI:https://10.1061/(ASCE)WR.1943-5452.0000488

Verones, F, MM Hanafiah, S Pfister, MAJ Huijbregts, GJ Pelletier, and A Koehler. 2010. Characterization Factors for Thermal Pollution in Freshwater Aquatic Environments. Environ. Sci. Technol. 44, 24, 9364-9369. DOI:

Turner, DF, GJ Pelletier, and B Kasper. 2009. Dissolved Oxygen and pH Modeling of a Periphyton Dominated, Nutrient Enriched River. ASCE J Env Eng, 135, 8. DOI:

Kannel, PR, S Lee, Y-S Lee, SRKanel, and GJ Pelletier. 2007. Application of automated QUAL2Kw for water quality modeling and management in the Bagmati River, Nepal. Ecological Modelling 202, 3-4, 503-517. DOI:

Pelletier, GJ, SC Chapra, and H Tao. 2006. QUAL2Kw – A framework for modeling water quality in streams and rivers using a genetic algorithm for calibration. Environmental Modelling & Software. 21, 3, 419-425. DOI:

Matthews, R, M Hilles, and G Pelletier. 2002. Determining trophic state in Lake Whatcom, Washington (USA), a soft water lake exhibiting seasonal nitrogen limitation. Hydrobiologia, 468, 1-3, 107-121. DOI: