“Extreme
El Niños, which spread warm water across the Pacific and warm the
globe, were not seen before 1982 and have occurred three times since.
Extreme El Niños are expected to increase in frequency as a result
of climate change.”
Coral
bleaching spreads to Maldives, devastating spectacular reefs
Exclusive:
Images from the Indian Ocean archipelago reveal the extent of the
longest global coral bleaching event in history
Michael
Slezak
Wednesday
1 June 2016 06.19 BST
The longest global
coral bleaching event in history is now devastating reefs in the
crystal clear waters of the Maldives, with images released
exclusively to the Guardian powerfully illustrating the extent of the
damage there.
Photographed by the
XL Catlin Seaview Survey, the images captured the event in May as it
moved beyond the now devastated Great Barrier Reef and into waters
further west.
“The bleaching we
just witnessed in the Maldives was truly haunting,” said Richard
Vevers, founder of the Ocean Agency.
“It’s rare to
see reefs bleach quite so spectacularly. These were healthy reefs in
crystal clear water at the height of an intense bleaching event. The
flesh of the corals had turned clear and we were seeing the skeletons
of the animals glowing white for as far as the eye could see – it
was a beautiful, yet deeply disturbing sight.”
The Maldives is
series of coral atolls, built from the remains of coral. The
livelihoods of people there depend on the reefs through tourism,
fisheries and as a wave-break that helps prevent inundation on
low-lying islands.
The photographs were
part of an ongoing project, in partnership with Google, the
University of Queensland and the US National Oceanic and Atmospheric
Agency to capture the global bleaching event as it moves around the
world.
“We’ve been
following this third global bleaching event since the start nearly
two years ago and just when you think you’ve seen the saddest sight
you’ll ever see, you see something even worse,” Vevers said.
The event started in
mid 2014 in the Pacific Ocean around Hawaii, which then got hit again
in 2015. In early 2016 it spread to the Great Barrier Reef where 93%
of its nearly 3,000 reefs were hit by bleaching.
Western Australia’s
reefs in the Indian Ocean have also experienced severe bleaching.
When Noaa declared
the event was a global bleaching event in October 2015, Mark Eakin,
Noaa’s Coral Reef Watch coordinator, said it could last well into
2016. That prediction appears to be proving correct.
“The current
global bleaching event is already lasted longer than any previous
bleaching event and is likely to last until at least the end of the
year,” he said.
The bleaching event
started with an El Niño that appeared to be developing in Pacific
Ocean, in 2014, warming the waters there, but which failed to
eventuate. It was then combined with a large patch of unusually
water, nicknamed “the blob”, that lurked around the Pacific, as
well as an extreme El Niño that eventually did develop in 2015.
Extreme El Niños,
which spread warm water across the Pacific and warm the globe, were
not seen before 1982 and have occurred three times since. Extreme El
Niños are expected to increase in frequency as a result of climate
change.
Those El Niños were
also occurring in an ocean where the surface has already warmed by
1C, putting corals near their thermal limits.
When coral sits in
water that is too warm for too long, it gets stressed and expels the
algae that provides it with about 90% of its energy. If it stays
stressed for more than a couple of weeks it starts to starve, become
diseased, and dies.
A new study has
found the conditions that led to the devastating bleaching on the
Great Barrier Reef were made 175 times more likely by climate change,
and on the current trajectory, would become the average conditions by
the 2030s.
Sem comentários:
Enviar um comentário