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Jennifer B. Korosi

Jennifer B. Korosi

Associate Professor


BScH, PhD, Queen's University

Research Keywords

Lakes; Environmental Change; Permafrost; Pollution; Biogeography; Biogeochemistry

Graduate Supervision

I supervise students in the graduate program in Geography

Jennifer B. Korosi

Contact Information

4700 Keele Street
Toronto, ON M3J 1P3

416 736 2100 (ext. 22491)

Google Scholar Profile


Research Interests

I am a limnologist (limnology = study of inland waters) who seeks to understand the underlying mechanisms and impacts of environmental change. Lakes are sentinels of environmental change. They reflect changes occurring within the lake as well as the watershed. Lakes also respond rapidly to climate change. My research uses lake sediment cores (the field of paleolimnology) to infer past environmental conditions and trajectories of ecosystem change. I study the role of climate warming and permafrost thaw as drivers of terrestrial and lake ecosystem transformation in cold regions. I am also interested in the role that climate change will play in altering the cycling and ecotoxicity of legacy contaminants.

Research Projects

Discontinuous Permafrost Partnership (DPP)

Role: Co-Investigator

Research Grant: NSERC Discovery Grant

Duration: 2020-2023

Summary: The discontinuous permafrost region of Canada's Northwest Territories (NWT) is one of the most rapidly warming on Earth. Unprecedented rates of permafrost thaw are transforming land covers, changing the flow, storage and quality of water, damaging infrastructure, and raising serious new concerns about the future availability and quality of northern water resources. The Discontinuous Permafrost Partnership (DPP) is an NWT-focused partnership of knowledge producers, mobilisers and users from universities, Indigenous communities, government and industry, working collaboratively to improve the understanding of and ability to predict and mitigate the impacts of permafrost thaw on the NWT's water resources.

Trajectories of landscape and lake ecosystem change in thawing permafrost landscapes

Role: Principal Investigator

Research Grant: NSERC Discovery Grant

Duration: 2017-2024

Summary: Permafrost, defined as soil or rock that remains frozen for at least two consecutive years, is a dominant feature of the Canadian landscape. Rates of permafrost thaw have accelerated in recent decades, a trend that will continue with future climate warming. The thawing of permafrost represents a major stressor on northern lakes that may negatively impact the provision of essential lake ecosystem services.  Empirical evidence of long-term impacts to lake ecological and biogeochemical function is lacking, as most studies into the effects of permafrost thaw on lakes are based on short-term observations. We are using paleoenvironmental techniques to track permafrost landscape change in the Northwest Territories, and the resulting lake ecosystem responses, over centennial to millennial timescales. Our field sites are based in the Inuvik-Tuktoyaktuk region (ice-rich, continuous permafrost), and the Dehcho region (discontinuous permafrost). 

Research Output

Persaud, A.A., Cheney, C.L., Sivarajah, B., Blais, J.M., Smol, J.P., and Korosi, J.B. (2021) Regional changes in Cladocera (Branchiopoda, Crustacea) assemblages in subarctic (Yellowknife, Northwest Territories, Canada) lakes impacted by historic gold mining activities. Hydrobiologia,

Hoskin, G.N., and Korosi, J.B. (2021) Long-term ecosystem change in two highly degraded Lake Ontario (Canada) coastal wetlands. Journal of Paleolimnology 65: 393-405.

Korosi, J.B., Thienpont, J.R., Eickmeyer, D.C., Kimpe, L.E., and Blais, J.M. (2020). A paleolimnological approach for interpreting Aquatic Effects Monitoring at the Diavik Diamond Mine (Lac de Gras, Northwest Territories, Canada). Lake and Reservoir Management 36: 297-313.

Cheney, C.L., Eccles, K.M., Kimpe, L.E., Thienpont, J.R., Korosi, J.B., and Blais, J.M. (2020) Determining the effects of past gold mining using a sediment palaeotoxicity model. Science of the Total Environment 718: 137308.

Coleman, K. A., Palmer, M. J., Korosi, J. B., Thienpont, J. R., Blais, J. M., and Smol, J. P. (2019). Assessing long-term changes in aquatic ecosystems near a small conventional oil and gas operation in the Cameron Hills, southern Northwest Territories, Canada. Fundamental and Applied Limnology, 192: 181-197

Korosi, J.B., Griffiths, K., Smol, J.P., and Blais, J.M. (2018). Trends in historical mercury deposition inferred from lake sediment cores across a climate gradient in the Canadian High Arctic. Environmental Pollution 241: 459-467.

Korosi, J.B., Thienpont, J.R., Blais, J.M., and Smol, J.P. 2017 Paleo-ecotoxicology: what can lake sediments tell us about ecosystem responses to environmental pollutants? Environmental Science & Technology 51: 9446-9457.

Korosi, J.B., Thienpont, J.R. ǂ, Pisaric, M.F.J., deMontigny; P., Perreault, J.T., McDonald, J., Simpson, M.J., Armstrong, T., Kokelj, S.V., Smol, J.P., and Blais, J.M. (2017) Broad-scale lake expansion and flooding inundates critical wood bison habitat. Nature Communications doi: 10.1038/NCOMMS14510.

Korosi, J.B., Eickmeyer, D.C., Thienpont, J.R., Palmer, M.J., Kimpe, L.E., and Blais, J.M. (2016) Assessing the contribution of combustion-derived contaminants to a remote subarctic environment from traffic on the Tibbitt to Contwoyto winter road (Northwest Territories, Canada). Science of the Total Environment 553: 96-106.

Korosi, J.B., McDonald, J., Coleman, K.A., Palmer, M.J., Smol, J.P, Simpson, M.J., and Blais, J.M. (2015) Long-term changes in organic matter and mercury transport to lakes in the sporadic discontinuous permafrost zone related to peat subsidence. Limnology and Oceanography 60: 1550-1561.

Korosi, J.B., and Smol, J.P. (2012) An illustrated guide to the identification of cladoceran subfossils from lake sediments in northeastern North America: Part 1 - the Daphniidae, Leptodoridae, Bosminidae, Polyphemidae, Holopedidae, Sididae, and Macrothricidae. Journal of Paleolimnology 48: 571-586.

Korosi, J.B., and Smol, J.P. (2012) An illustrated guide to the identification of cladoceran subfossils from lake sediments in northeastern North America: Part 2 – the Chydoridae. Journal of Paleolimnology 48: 587-622.

Korosi, J.B., Burke, S.M., Thienpont, J.R., and Smol, J.P. (2012) Anomalous rise in algal production linked to lakewater calcium decline through food web interactions. Proceedings of the Royal Society Biological 279: 1210-1217.

Scugog Lake Stewards, educational outreach videos (2017-2018)

Recognition & Awards

  • J.C. Stevenson Award & Plenary Lecture (2020), Canadian Journal of Fisheries and Aquatic Sciences “A lectureship conferred upon a young, energetic and creative researcher at the cutting edge of an aquatic discipline”.
  • Dean’s Award for Distinction in Research (Emerging Researcher), Faculty of Liberal Arts and Professional Studies, York University
  • Julian M. Szeicz Award for Early Career Achievement, Canadian Association of Geographers
  • Early Researcher Award, International Paleolimnology Association
  • Petro-Canada Young Innovator Award, York University


Course CodeTitle
EU/SC/GEOG 2500 3.00 Introduction to Vegetation and Soils
EU/SC/GEOG 3500 3.00Biogeography
EU/SC/GEOG 4200 3.00Water Quality and Stream Ecosystems
GS/GEOG 5610 3.00Biogeochemistry of Stream Ecosystems         
GS/GEOG 5600 3.00Research Seminar in Physical Geography