Comparative analyses: Coral reefs and global change

Beyond our focal research on Kiritimati, we also conduct large comparative empirical analyses to examine how coral reefs are changing globally. Our global meta-analysis of the impacts of El Niño and La Niña events on coral reefs (Claar et al. 2018 PLoS ONE) showed that coral cover losses during El Niño/La Niña were shaped by localized maximum heat stress and long-term mean temperature, and that the 2015/16 El Niño event instigated unprecedented global coral heat stress across the world's oceans:

El Niño events with the greatest heat stress. Both figures show which El Niño event caused the greatest maximum degree heating weeks for each area of the world’s oceans. a) All El Niño events from 1982 to 2010, showing heterogeneity in the geographic distribution of the most extreme heat stress. b) All El Niño events since 1982, including the 2015-2016 El Niño event, demonstrating the heat stress homogenization that occurred during this most recent warming event (Claar et al. 2018).

We also contributed to a global coral reef analysis showing that the return time between severe heat stress events is now insufficient for coral reef communities to recover (Hughes et al. 2018 Science). See our Media page for more on this latter paper.