Shell Day- regional collaboration and citizen science further understanding of coastal acidification

Coastal ecosystems and their resources for society are being affected by coastal and ocean acidification. Our understanding of these effects and future scenarios is limited in view of the complexity of biogeochemical and biological processes in coastal waters and of restricted monitoring capacity. Existing efforts from buoys and monitoring programs can greatly benefit from expanding capacities by regional collaborations of organizations involved in water quality studies and of citizen’s interest and involvement in science participation. Here, we present the results of more than 50 organizations that engaged in a monitoring “blitz” day throughout the Northeast U.S. on August 22, 2019. From Long Island Sound in the south to the Downeast Maine coast, these organizations simultaneously collected water samples at low, mid, and high tide at more than 80 sites to provide a snapshot of seawater conditions affecting shellfish and other coastal resources. This “Shell Day” of 2019 aimed to examine how the buffering capacity of seawater (or total alkalinity, TA) varies across the region and its relationship with salinity in different embayments. Each sampling group collected a minimum of five water samples, measuring temperature and salinity along a tidal cycle at one site. Bottle samples were preserved and sent on ice to participating laboratories for TA analysis. This presentation will discuss results of sample analysis. Although a moment in time, these results will advance our broad geographic scale perception of TA variability across the coastal Northeast of the United States. Shell Day has already accomplished a goal of connecting scientists, nonprofit organizations, and the public to promote collaboration in regional monitoring, public education, and better environmental governance.