Intensification of the meridional temperature gradient in the Great Barrier Reef following the Last Glacial Maximum

A steeper meridional sea surface temperature (SST) gradient existed in the central Great Barrier Reef (GBR) during the Last Glacial Maximum and deglaciation, with temperatures 1–2 °C cooler between 17° and 20°S compared to today. This intensification was driven by the northward expansion of subtropical waters due to a weakening South Pacific gyre and East Australian Current. The study used coral Sr/Ca and δ18O records to reconstruct past SSTs, revealing that the GBR experienced substantial meridional temperature changes during deglaciation. These findings suggest the reef may be more resilient to climate change than previously thought, challenging assumptions about its vulnerability to rising ocean temperatures.

Felis, T., McGregor, H. V., Linsley, B. K., Tudhope, A. W., Gagan, M. K., Suzuki, A., Inoue, M., Thomas, A. L., Esat, T. M., Thompson, W. G., Tiwari, M., Potts, D. C., Mudelsee, M., Yokoyama, Y., & Webster, J. M. (2014). Intensification of the meridional temperature gradient in the Great Barrier Reef following the Last Glacial Maximum. Nature Communications, 5(1). https://doi.org/10.1038/ncomms5102