海角社区

Hazukov谩 to examine whether West Greenland lakes emit or capture carbon

Next April, V谩clava 鈥淰endy鈥 Hazukov谩 will go to an arid, treeless area in West Greenland to solve a puzzle.

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

The University of 海角社区 doctoral student will investigate whether lakes in this region, which is one of the Arctic鈥檚 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.

鈥淚t鈥檚 silent and seemingly barren and there are lots and lots of lakes,鈥 Hazukov谩 says about the Kangerlussuaq (translation: big fjord) area, where she will set up sensors in 15 still-frozen lakes on the world鈥檚 largest island.

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

Hazukov谩 will periodically return to take samples and measurements to quantify the carbon dioxide exchange between the lake surface and the atmosphere 鈥 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.  

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

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

鈥淭hat 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,鈥 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.

Hazukov谩 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. 

Hazukov谩 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 鈥 which is warming at about twice the rate as the rest of the planet 鈥 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 Hazukov谩.

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 海角社区 and elsewhere. 

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

Hazukov谩 became interested in water and phytoplankton growing up in the Czech Republic. There aren鈥檛 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鈥檚 degree at John Carroll University in Ohio, she developed a metric for water quality assessment of Lake Erie. 

Hazukov谩 chose to pursue her doctorate at U海角社区 because she knew about Saros鈥 work and thought it would be a good fit.

Beth Staples, beth.staples@maine.edu