Every one of the world’s coral reefs could bleach by the end of the century, unless there are drastic reductions in greenhouse-gas emissions, the United Nations Environment Programme (UNEP) has warned. “In the face of inaction, coral reefs will soon disappear,” Leticia Carvalho, head of UNEP’s Marine and Freshwater Branch said on Monday. “Humanity must act with evidence-based urgency, ambition and innovation to change the trajectory for this ecosystem, which is the canary in the coalmine for climate’s impact on oceans, before it’s too late.” In its report Projections of Future Coral Bleaching Conditions, UNEP outlines the links between coral bleaching and climate change. It postulates two possible scenarios: a “worst-case scenario” of the world economy heavily driven by fossil fuels; and a “middle-of-the-road” wherein countries exceed their current pledges to limit carbon emissions by 50 per cent. Under the fossil-fuel-heavy scenario, the report estimates that every one of the world’s reefs will bleach by the end of the century, with annual severe bleaching occurring on average by 2034, nine years ahead of predictions published three years ago. Should countries achieve the “middle-of-the-road” scenario, severe bleaching could be delayed by eleven years, to 2045, adds UNEP.
By UN News. December 22, 2020.