Ocean gliders are autonomous instruments that traverse the water column making physical observations including irradiance, temperature, salinity and turbidity. Analysis of glider flight data enables derivation of other physical characteristics such as currents and flow. Three parameters critical to coral stress – flow, temperature and irradiance – are influenced by upper ocean turbulence, which is notoriously difficult to measure. We investigated whether glider flight data along with observations can be used as a proxy for measurements of turbulence in the context of coral bleaching events on the Great Barrier Reef (GBR). Australia’s Integrated Marine Observing System (IMOS) has operated gliders in the GBR for ~10 years, building a comprehensive non-continuous dataset of observations collected during both bleaching and non-bleaching conditions that is all published and freely available via the Australian Ocean Data Network (AODN). Analyses demonstrate that sea surface temperature was not the same as benthic temperature during stratified conditions that immediately preceded mass coral bleaching events in 2016, 2017 and 2020. Stratification of this intensity was not observed in non-bleaching years (2018, 2019). Summer in bleaching years was marked by observations of stratification during periods of low ocean turbulence, when vertical mixing processes were reduced, concentrating heat in the upper ocean.