The FjordPhyto citizen science project in the Antarctic Peninsula

FjordPhyto, funded by the United States National Science Foundation (NSF) in 2016-2019 and by the National Aeronautics and Space Agency (NASA) Citizen Science for Earth Systems Program IN 2021, is a citizen science project that examines the impacts of increasing glacier meltwater on local ecosystems at the ice-ocean interface of the Antarctic Peninsula (AP), with an emphasis on the western coast (WAP). The citizen science module is based on a collaboration with the International Association of Antarctica Tour Operators (IAATO). Citizen scientists participate in a “validation safari” in which satellite data informs sampling to validate and refine a new ocean color algorithm to detect the glacial meltwater content of seawater from space. The in-situ measurements are combined with remote sensing data products to address scientific questions related to the impacts of glacial meltwater on phytoplankton community abundance and taxonomic composition. This project implements new field sampling techniques and conducts analyses of phytoplankton diversity through a microscopic and genomics approach. The scientific goals of this Citizen Science project are to determine the spatial extent of glacial meltwater through the seasons and identify concomitant shifts in phytoplankton abundance and community diversity in coastal Antarctic waters. Repeated sampling of this region from November to March along 3-6 degrees of latitude (62° S to 65° S and down to 68° S) is only feasible with tourist ships, or through remote sensing. The addition of a remote sensing component, validated by citizen scientists, is crucial for describing long-term synoptic trends and variability in the abundance and spatio-temporal extent of phytoplankton in this region, and for discerning how these patterns are likely to alter in response to changes in climate. This study provides a foundation to better understand phytoplankton diversity under current and potential future ocean conditions, and lead to more robust predictions on potential impacts to upper trophic levels and biogeochemical cycling within this rapidly changing ecosystem.

Methods
Samples were collected by the FjordPhyto Citizen Science program (www.fjordphyto.org; Cusick et al. 2020), created in 2016-2017 with tour operator expedition vessel members of the International Association of Antarctica Tour Operators (IAATO) to collect oceanographic data from surface ocean waters. Samples were taken from November to March at numerous locations along the Antarctic Peninsula (AP), mostly in the western side, between King George Island (62° S, 58° W) and Marguerite Bay (near 68° S) with the help of travelers visiting the inshore (< 0.2 km from shore) and nearshore (0.2 to 40 km from shore) regions in the WAP.

Samples were collected from surface waters from an inflatable boat (e.g., a Zodiac) during their visits to the AP, from 2016 to present day, including a CTD (Conductivity-Temperature-Depth sensor) profile between 0 and down to 100m depth, determination of a Secchi depth, surface seawater fixed in Lugol's solution for microscopy analysis, a surface net tow (20-micron mesh) for genetic eDNA analysis (16S/18S). Other measurements were added in 2021, including water samples for seawater 18-Oxygen determination and optical properties with a HydroColor app.