Bioaerosol Sources and Sinks in Northern Alaska: a Microbiome Study

MARINA NIETO-CABALLERO, Jessie Creamean, Thomas C. J. Hill, Kevin R. Barry, Christina S. McCluskey, Thomas A. Douglas, Paul DeMott, Sonia Kreidenweis, Colorado State University

     Abstract Number: 525
     Working Group: Bioaerosols

Abstract
As a result of Arctic air temperatures rising at more than twice the global rate, permafrost and ice wedges are rapidly thawing, releasing greenhouse gas reservoirs, and microorganisms with greenhouse gas-generating metabolism. Thawed permafrost landslides are also increasing due to warming temperatures, introducing thawed soil into a range of water bodies (i.e., ocean, rivers, and lakes). Microorganisms from thawed permafrost and ice wedges discharged to these water bodies can ultimately be aerosolized through wind-driven and/or greenhouse gas bubble bursting in thermokarst lakes. In addition, these airborne biological particles can be a potential source of biologically-derived ice nucleating particles (INPs) at warm temperatures (≥ -10^oC), potentially altering cloud dynamics in Arctic regions.

In this study, we present data from environmental samples collected during Summer 2021 in Northern Alaska (Utqiaġvik region), including air, water (i.e., ocean, rivers, and thermokarst lakes), permafrost, ice wedge, and vegetation samples, as well as aerosol particle distribution data. Here, we present results processed for 16S rRNA gene sequencing to identify and classify microorganisms, showing for the first time how microorganisms in permafrost, ice wedges, vegetation, and different water bodies are potential sources and sinks of bioaerosols in Northern Alaska, based on amplicon DNA analysis. The obtained air microbiome results are additionally linked to air mass back trajectories calculated with NOAA’s HYSPLIT model. This study is part of the multidisciplinary ARCSPIN project (ARCtic Study of Permafrost Ice Nucleation), which additionally includes INP analysis, as well as aerosol and INP modeling.