Temperature Response of South Florida Estuaries to the 2023 Heatwave

Abstract

While a record-high in situ water temperature of 38.4 °C on July 24, 2023, has been measured from a local site in Florida’s Manatee Bay, satellite images revealed more extensive record-high water temperature in South Florida estuaries and the Florida Keys Reef Tract in July 2023 as a response to the 2023 heatwave, with an average sea surface temperature (SST) anomaly of 1.59 °C above the 2003–2022 mean. Long-term annual SST anomalies and long-term SST trend components of the time series both show significant warming trends in these regions between 2003 and 2023 (0.70 °C/decade), which is 67% higher than in the Gulf of Mexico (0.42 °C/decade). Furthermore, the warming trend appears to have accelerated over the past decade. In the context of global warming in the twenty-first century, such a warming trend and response to heatwaves may lead to more heat stress on the precious coral reefs and seagrasses both in and downstream from these already fragile estuaries.