Hazuková to examine whether West Greenland lakes emit or capture carbon

A lake in Greenland

Next April, Václava “Vendy” Hazuková will go to an arid, treeless area in West Greenland to solve a puzzle.

It’s not known how lakes there contribute to Arctic carbon cycling — the process in which carbon atoms move from the atmosphere to the Earth and back. Where carbon is — including in the atmosphere, oceans, lakes, rocks and permafrost — is constantly in flux.

The University of Maine doctoral student will investigate whether lakes in this region, which is one of the Arctic’s most arid, emit or capture carbon.

Her research comes at a time when the amount of CO2 in the atmosphere is over 400 parts per million and July 2021 was the hottest month ever recorded on Earth.

“It’s silent and seemingly barren and there are lots and lots of lakes,” Hazuková says about the Kangerlussuaq (translation: big fjord) area, where she will set up sensors in 15 still-frozen lakes on the world’s largest island.

The sensors will record carbon dioxide at a high frequency over the course of a year.

Hazuková will periodically return to take samples and measurements to quantify the carbon dioxide exchange between the lake surface and the atmosphere — both under ice and when the lakes are ice-free, as well as during the shoulder seasons.

She received a $58,396 National Science Foundation Arctic System Science Doctoral Dissertation Research Improvement Grant for the project.

Hazuková is teaming with Jasmine Saros, associate director of the Climate Change Institute and professor of paleolimnology and lake ecology.

They’ll compare their carbon exchange findings with other scientists’ data from lakes in different landscapes and different climates across the entire Arctic.

“That will allow us to better understand spatial variation in carbon dioxide fluxes and put into perspective the magnitude of carbon fluxes from our study lakes in drier Arctic landscape,” she says.

West Greenland could serve as a model landscape for examining implications of a warmer and drier Arctic for carbon dynamics in inland waters.

Hazuková will use the project to build on her dissertation research, which focuses on how metabolic processes and carbon dynamics in West Greenland lakes respond to rapid climate change and earlier ice-out.

Ice-out in West Greenland lakes has advanced six days since 1993, but variability in ice-out timing is substantial; in 2018, ice-out was in mid-June and in 2019, it was at the end of May.

Hazuková is analyzing lake temperature data that Saros and others collected over the past 20 years from Kangerlussuaq lakes.

She seeks to understand how ice-out dynamics affect open water processes, how temperatures change both in the surface and bottom waters and, ultimately, the biological impacts of these thermal changes.

Together, the studies will provide important information about the cascading effects of climate warming on lake carbon and ecosystem dynamics.

Dramatic changes in the Arctic — which is warming at about twice the rate as the rest of the planet — have been documented. And the drier and warmer conditions that exist now in West Greenland are indicative of likely future conditions in many Arctic regions, says Hazuková.

That will have implications for carbon cycling, biological communities and, in some areas, could exacerbate wildfire frequency and intensity.

The Arctic climate also impacts lower latitudes. Changing sea ice dynamics in the Arctic Ocean and increasing ice melt from the Greenland ice sheet are connected with unusual weather patterns in Maine and elsewhere.

Enhancing understanding of the linkages between rapid climatic changes in the Arctic and Maine is a focal point of a new National Science Foundation Research Traineeship project led by Saros.

Hazuková became interested in water and phytoplankton growing up in the Czech Republic. There aren’t a lot of natural lakes in the landlocked country, but there are numerous ponds made centuries ago to harvest carp and other fish.

While earning her undergraduate degree at the University of South Bohemia, she investigated diversity patterns and seasonal shifts of algal communities in those shallow fish ponds.

And when studying for her master’s degree at John Carroll University in Ohio, she developed a metric for water quality assessment of Lake Erie.

Hazuková chose to pursue her doctorate at UMaine because she knew about Saros’ work and thought it would be a good fit.