丁香园AV

Program: PhD

Supervisor: Lance Lesack

Education: B.Sc. Ecosystem Science & Sustainability, Colorado State University (USA). M.Sc. Civil Engineering, University of Hawai驶i at M膩noa (USA). 

Personal website url: https://hannahharrison54.wixsite.com/website

Research description/interests: Hydrodynamics and biogeochemistry of methane (CH4) in highly productive Arctic Delta lakes (Mackenzie Delta, Northwest Territories)

Biography: Lakes in the Mackenzie Delta act as a CO2 to CH4 shunt, seemingly serving as a carbon sink by net absorbing CO2, but then re-emitting carbon in the more potently climate-forcing CH4, ultimately serving as net CH4 sources to the atmosphere. The timing and amount of these emissions seem to be sensitive to the duration of ice cover and the timing of ice formation and ice melt on the lakes, which relate to the hydrodynamics of the lakes. During under-ice anoxic periods, CH4 can increase by 4,000%, but in some lakes, not all of this CH4 is emitted every year. My research is focused on examining the relationship between incomplete water column mixing and CH4 retention following ice off and how under-ice CH4 circulates. By studying these aspects of the lakes, my research will better inform bottom up calculations of natural CH4 emissions from climate-sensitive aquatic Arctic systems and present a clearer understanding of the quantity and timing of CH4 fluxes to the atmosphere from large Arctic deltas.

To do this research, I conduct fieldwork out of the Western Arctic Research Centre to deploy thermistor arrays and OsmoSamplers in collaboration with Laura Lapham (University of Maryland Center for Environmental Science) and Sally MacIntyre (University of California 鈥� Santa Barbara)

Awards: 丁香园AV Graduate Entrance Scholarship (2021), 丁香园AV Graduate Fellowship (2022)

Teaching Assistantships:

BISC 414 鈥� Limnology

GEOG 104 鈥� Climate Change, Water, and Society

GEOG 226W 鈥� Geography in Practice

Publications:

Harrison, H. N., Hammond, J. C., Kampf, S., & Kiewiet, L. (2021). On the hydrological difference between catchments above and below the intermittent-persistent snow transition. Hydrological Processes, 35(11), e14411.

Harrison, H. N., & Singh, A. (2020). Modern evaluation of the status of WOTUS. Journal of Legal Affairs and Dispute Resolution in Engineering and Construction, 13(1), 03720006.

Kampf, S. K., Burges, S. J., Hammond, J. C., Bhaskar, A., Covino, T. P., Eurich, A., Harrison, H., Lefsky, M., Martin, C., McGrath, D., Puntenney-Desmond, K., Willi, K. (2020). The case for an open water balance: Re-envisioning network design and data analysis for a complex, uncertain world. Water Resources Research, 56(6), e2019WR026699.