Estuary Acidification: A five-year perspective on pH in Possession Sound, Washington

• Main Author: Haucke, Alexa
• Format: Text
• Language: English
• Published: Western CEDAR 2022
• Subjects: Ocean acidification
• Online Access: https://cedar.wwu.edu/ssec/2022ssec/allsessions/121; https://cedar.wwu.edu/context/ssec/article/3283/viewcontent/136_f13092327ea94b07a82dc79dd35a6cdb.pdf

pH is the primary factor in ocean acidification. It is influenced by water chemistry, biological aspects, seasonal changes, and human activity. Low pH (acidic conditions) can contribute to hypoxia, coral bleaching, and other dangerous conditions for the ecosystem. In this study, the effects of ocean acidification in Possession Sound were examined over a five-year period, with the context of seasonal plankton blooms and changes in river discharge. This was accomplished using a YSI EXO Sonde periodically deployed nearshore in Mukilteo, Washington, USA used in partnership with Ocean Research College Academy. This site, being within the Snohomish River Estuary, is affected by both oceanic factors, as well as the Snohomish River and any runoff that comes through those waters. These measurements create a depiction of changing pH in Possession Sound. This suggests that the area goes through cycles of pH levels throughout the year, with the most prominent trends being seasonal and related to upwelling. As climate change progresses, consistent monitoring of ocean pH will be essential to preserving marine and estuarine ecosystems. This study contributes to the growing body of knowledge on the impact of ocean acidification, which is vital to the future of the Salish Sea and the communities that rely on it.