Exploring the Dynamics of Sea Surface Temperature Change over the Past Four Decades

It is clear that sea surface temperatures have increased continuously since the 1970s, but few extensive investigations of the fine-scale dynamics of sea surface temperature change that results in the warming trend have been carried out. It is largely unknown how the intensity, duration and frequency of sea surface temperature anomalies have evolved worldwide with increasing sea surface temperature. This presentation examines the change over the past four decades in sea surface temperature variability and the structure of periods of elevated sea surface temperature which can have significant impacts on marine ecosystems. For example, is the reported increase in frequency and intensity of heat stress events driven more by the magnitude of sea surface temperature anomalies or the duration of positive anomalies?

The objective is achieved by statistical analysis of the new CoralTemp (v1.0) dataset from the NOAA Coral Reef Watch program, a globally complete daily sea surface temperature dataset with high spatial resolution (0.05º × 0.05º). The analysis sheds light on the dynamics of marine climate extremes, sometimes known as marine heatwaves, and the implications for marine ecosystems. Previous studies have demonstrated that the resistance of some marine communities (e.g., tropical corals) to extreme thermal disturbance is associated with the experienced sea surface temperature variability. Our results may improve the understanding of sea surface temperature variability, and thereby benefit predicting impacts of changing frequency and intensity of marine heatwaves on marine life.