Cold-water corals, like those off the coast of British Columbia, are as threatened by global warming as their tropical counterparts The hurricane season begins with a bang: Beryl is the first Category 5 storm to form in the Atlantic Ocean. This storm has been downgraded to a Category 4, but was still expected to hit Jamaica with life-threatening winds and tides on Wednesday.
Coral reefs are generally a vital form of natural coastal protection against storms. But warmer ocean waters are putting its future in doubt, even as hurricanes are expected to get stronger. When the water gets too hot, corals – which are living things – bleach and sometimes die.
“Unfortunately, the storms are getting bigger and more intense, and this is due to climate change,” said Nicola Smith, an associate professor of biology at Concordia University who has studied coral reefs in the Bahamas. “Reefs that are capable of protecting these communities are being lost, at the same time [the communities] are going to need that protection more than ever.”
How coral reefs protect the coast
Jennifer Koss, who studies coral reef conservation, describes them as “nature’s dam.” “You have this huge bulwark that essentially acts as a big source of friction and slows down the waves, crushes them and prevents a lot of that energy from reaching the shore,” explained Koss, director of the Administration’s coral reef conservation program. US National Oceanic and Atmospheric Administration (NOAA).
Research suggests that coral reefs can reduce wave energy by an average of 97%. That is why they are “absolutely essential to protect low-lying islands from damage,” said Michael Risk, professor emeritus of Earth, Environment and Society at McMaster University. Studies have also shown that coral reefs have the ability to regenerate if damaged during storms, and to grow upward to protect themselves from rising sea levels.
Mass whitening
But coral reefs face unprecedented ocean warming. Almost all coral reefs in the Atlantic, off the coast of Florida and in the Caribbean, have suffered serious losses. NOAA confirmed mass bleaching on a global scale in April.
“When these bleaching episodes last too long, the tissue dies and a white skeleton is seen. Over time, that hardened structure erodes and the protective value of the reef is lost,” Koss explained.
“If corals do not have enough time to recover from mass bleaching, over time we lose this valuable structure… not only for coastal protection, but for biodiversity, food security and many other ecosystem services that corals provide. “he added.
According to Risk, warming oceans and land pollution put the future of coral reefs in question. The expert warned that after the death of the corals, the structure remains in place for a maximum of a decade. Researchers strive to prevent bleaching, in some cases, according to Koss, by physically shading the water over coral reefs.
Koss said a hurricane or tropical storm can also help cool the water and relieve pressure on coral reefs, as long as the storm is not too powerful and does not hit them directly. “As a conservationist, it’s crazy to pray for a storm or prolonged exposure to clouds to slow the impact of bleaching,” Koss said. The hurricane season, which runs from June 1 to November 30, is expected to be more eventful than usual this year.
