International Journal of Waste Resources

Antarctic permafrost degassing in Taylor valley by extensive soil gas investigation

World Congress on Sustainable Waste Management

June 21, 2023 | Webinar

Alessandra Sciarra

National Institute of Geophysics and Volcanology, Italy

Scientific Tracks Abstracts: Int J Waste Resour

Abstract:

Contemporary studies conducted in northern Polar Regions reveal that permafrost stability plays an important role in the modern carbon cycle as it potentially stores considerable quantities of greenhouse gases. Rapid and recent warming of the Arctic permafrost is resulting in significant greenhouse gas emission, both from physical and microbiological processes. The potential impact of greenhouse gas release from Antarctica is now also being investigated. In Antarctica, the McMurdo Dry Valleys comprise 10% of the ice-free soil surface areas in Antarctica and like the northern Polar Regions are also warming albeit from lower mean temperatures. The work presented herein examines a comprehensive sample suite of soil gases (e.g., CO2, CH4 and He) concentrations and CO2 flux measurements conducted in the Taylor Valley during the Austral summer 2019/2020. Analytical results reveal the presence of significant concentrations of CH4, CO2 and He (up to 18,447 ppmv, 34,400 ppmv and 6.49 ppmv, respectively) at the base of the active layer. When compared with the few previously obtained measurements, we observe increasing CO2 flux rates (estimated CO2 emission in the study area of 21.6 km2 ≈ 15 tons/day). The distribution of the gas anomaly, when compared with geophysical investigations, implies an origin from deep brines migrating from inland (potentially from beneath the Antarctic Ice Sheet) towards the coast beneath the permafrost layer. These newly obtained data provide a baseline for future investigations aimed at monitoring the changing rate of greenhouse gas emission from Antarctic permafrost, and the potential origin of gases, as the southern polar region warms.

Biography :

Alessandra Sciarra has her expertise in environmental geochemistry. Her research activity is focused on: fluid geochemistry surveys (soil gases concentration, fluxes measurements and dissolved gases in the water) and gas chromatographic analyses, geostatistical and graphical elaboration of geochemical data, in the frame of Diffuse and Natural Degassing Systems, liquefaction and sinkhole phenomena, CO2 and Natural Gas Geological Storage, geothermal resources, natural radioactivity, mitigation of environmental risk, qualitative e quantitative evaluation of gas desorbed from coal, geochemical monitoring of active faults, volcanic and seismic areas; seismic and tsunami genic monitoring of National Seismic Network 24 hours a day of the Italian territory. She is the scientific manager of the fluids geochemistry laboratory of Roma and she was scientific and technical leader of many national and European research projects. The said activities were carried out both nationally and abroad (Greece, Cuba, Argentina, Mexico, Mozambique, Turkey, Indonesia, Iceland, Egypt, Brazil, Romania, Azerbaijan, and Antarctica).