Abstract
An evaluation of 20 years (2001-2021) of monthly data from a long-term monitoring program was performed to determine the temporal, seasonal and spatial changes in the distribution of salinity, temperature, dissolved oxygen, and pH, to identify the potential impacts of climate change on Biscayne Bay, the largest estuary on the Atlantic coast of Florida. Data were evaluated by decade, season, and zone. Decade 2 showed higher salinity in four of eight zones, along with saltwater intrusion in the bottom layer of some canals. The zones most influenced by the Atlantic Ocean did not show decadal salinity changes. In decade 2, the overall median temperature increased (+0.5 degrees C), with North Bay exhibiting the highest increase (+0.8 degrees C). In decade 2, dissolved oxygen was higher in four zones, while pH decreased in six zones, suggesting that ocean acidification is also influencing the Bay. Temperature, dissolved oxygen, and pH displayed pronounced seasonal patterns across zones. Collectively, these results suggest that sea level rise and climate change are gradually transforming Biscayne Bay from an estuarine system to one that is more marine in nature.