Coral reefs worldwide have been stressed by pollution, warmer seas, and outright destruction by men. Cyclones add another hazard.
Globally, coral reefs reached their majestic peak by the mid-20th century. The first large-scale coral die-off from marine heat was during the 1982–1983 El Niño. 6 such events have occurred since, with the latest underway in spring 2020.
Indirect insults to coral reefs have come from air pollution which diminish sunlight, water pollution from agricultural chemical runoff, plastic which sickens coral, and overfishing of fish which help keep reefs healthy.
Coral reefs have also been directly destroyed to harvest clams, provide deep-water ports for ships, and as a casualty of careless construction on shores and islands.
Global warming is making cyclones more frequent and intense. These storms can damage coral reefs from as far as 1,000 km (>600 miles) from a cyclone’s eye.
Cyclone strength is not the sole factor influencing destructive impact on coral. The size of a cyclone and how long it lingers are equally important in generating waves which batter coral. Global warming is amplifying cyclones in these characteristics, rendering tropical storms an increasing destructive force to coral reefs.
The trajectory of coral reef devastation indicates that these marine metropolises, in which some 25% of the ocean’s fish live, may be gone by 2030.
References:
Ishi Nobu, “Coral reefs,” in The Fruits of Civilization, BookBaby (2019).
Ishi Nobu, ” Stormy weather,” (25 May 2020).
Marjetta Puotinen et al, “Towards modelling the future risk of cyclone wave damage to the world’s coral reefs,” Global Change Biology (25 May 2020).
“Cyclones can damage distant coral reefs 1000 km away – 10x further than conventional modeling,” SciTech Daily (27 May 2020).