http://www.truth-out.org/news/item/39569-alarming-new-coral-bleaching-event-has-begun-at-the-great-barrier-reef
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Alarming New Coral Bleaching Event Has Begun at the Great Barrier Reef
Wednesday, February 22, 2017 By Dahr Jamail, Truthout | Report
Great Barrier Reef, Queensland, Australia -- After a major coral
bleaching event killed 22 percent of the Great Barrier Reef (GBR) in
2016, the reef is once again undergoing what could be another major
bleaching event.
Coral bleaching occurs when corals become stressed by warmer-than-normal
water, causing them to expel symbiotic algae that lives in their tissues
from which they get their energy. Coral turns completely white when it
bleaches, and if it remains bleached long enough, it dies.
Last week, I investigated several areas along the outer edge of the reef
and closer to shore with members of the Great Barrier Reef Legacy, a
nonprofit environmental organization that works to promote better
stewardship of the reef by providing free access for scientists. In the
areas I saw firsthand, 10 percent to 95 percent of all the coral was
already undergoing bleaching (depending on the location).
Coral bleaching occurs when water temperatures become too warm for the
coral to survive. If the waters do not cool back down within 3-6 weeks
from when the bleaching event begins, the coral will die.
"95 percent of all this coral is now bleached," John Rumney, the
managing director of Great Barrier Reef Legacy, told Truthout upon
surfacing from snorkeling in an area northeast of Port Douglas,
Australia. Rumney was referencing this specific area, and said, "The
question is, how long will it stay bleached, and what will the mortality
rate be?"
Losing the Great Barrier Reef?
The coral, which is normally vibrant shades of most of the colors of the
rainbow when healthy, turns completely white when bleached.
"This bleaching event will continue -- there's nothing to indicate that
this will not continue," Rumney told Truthout while pointing to the
reefs we'd just seen.
During last year's major bleaching event, the largest ever recorded to
have struck the GBR, 93 percent of the area of the reef was impacted.
When the coral spawned during last November and December, there was less
spawning than usual, since more than one-fifth of the reef had died.
Hence, large areas have been unable to recover from the 2016 event, and
another event is already well underway. According to Rumney, who has
been diving the reef for 42 years, the new event is already extensive.
"This coral is in big trouble," Rumney said. "Compared to the 2016
event, it definitely did not bleach this bad in this area last year." He
noted that the current bleaching event is further inshore than last
year's, and has also extended further to the south.
The death of this coral is, undoubtedly, globally significant. The Great
Barrier Reef, off the Eastern Coast of Australia, is the largest living
thing on Earth. Easily visible from space, the 1,400-mile-long,
133,000-square-mile ecosystem is home to more than 1,500 species of fish
and over 600 types of hard and soft corals. Portions of the reef have
been dated as old as 20 million years.
Yet, particularly with the advent of this most recent event, this World
Heritage Site is now on the brink of vanishing. Warming ocean waters are
regularly causing coral bleaching. Agricultural pesticides and
fertilizers, along with sediment runoff, dredging and land-mining
operations are contributing to the demise, but human-caused climate
disruption remains the reef's primary nemesis.
A 2012 study revealed that half of the Great Barrier Reef had already
vanished in just the previous 27 years. Two years later, the world's
most qualified coral reef experts released a report showing that,
without dramatic intervention, the Great Barrier Reef would disappear
completely by 2030.
"According to coral records from the reef, we've never seen bleaching
events like this,"
Dr. Dean Miller, a marine scientist and director of science and media
for the Great Barrier Reef Legacy, told Truthout on the boat.
This writer, along with Rumney and Miller, investigated several other
areas of the GBR, including the outer reef. One area of the outer reef,
immediately adjacent to a 6,000 drop-off into the deep sea, was at least
50 percent bleached out, while two other outer reef areas ranged from
approximately 10 to 30 percent bleached.
Permanent Global Bleaching Events
A February 14 report from the National Oceanic and Atmospheric
Administration (NOAA) shows a 60 percent probability of all global coral
bleaching from thermal stress (warm waters) from this month through May
2017.
However, the same report indicates that the Far Northern and Northern
GBR are already under a bleaching warning. These areas are classified as
"Alert Level 1," which means bleaching is likely. Meanwhile, Alert Level
2 conditions (meaning that coral mortality likely) exist for the North,
Central and Southern GBR.
This means that, at this moment, the entirety of the GBR is already in
either Alert Level 1 or Alert Level 2 coral bleaching conditions.
As of February 2017, what is occurring at the Great Barrier Reef is the
longest and most widespread coral bleaching event ever recorded,
according to NOAA.
According to a 2016 Climate Council of Australia report about the major
coral bleaching event that killed 22 percent of the reef, a
"catastrophe" was underway along the GBR because sea surface
temperatures were 1C above their recent long-term average (2002-2011),
due to ACD-driven record-breaking surface temperatures across the region.
The report, at the time, said the GBR was "at a crisis point," setting
the stage for this new bleaching event, which may prove to be as bad as
the event that hammered the reef last year.
It is also worth noting that El Niño, which was blamed for the extremely
warm seawater temperatures behind the bleaching event last year, has
already passed.
A 2016 study published in the prestigious journal Nature predicted that
by the year 2050, more than 98 percent of global coral reefs will be
afflicted by "bleaching-level thermal stress" every single year. A 2011
NOAA report had already warned that all of the world's coral reefs could
disappear by 2050, barring " urgent action" to stop warming seas,
extreme weather events and ocean acidification, as well as overfishing,
coastal development, agricultural runoff and shipping.
The NOAA report warned that 90 percent of all reefs would be threatened
by 2030, and nearly all reefs will be at grave risk by 2050.
While that might sound extreme, Miller told Truthout he thought the
report actually didn't go far enough.
"I think it's too conservative, I really do," he explained. "Corals need
hundreds of years to adjust to the warmer ocean waters, and we don't
have that kind of time anymore. The warming we are seeing now is
happening far too fast to allow for evolution…. So what we're seeing now
is death. That's what bleaching is."
Rumney's assessment of what life without coral might look like was
equally bleak.
"When all that coral goes, all that diversity of fish that depends on it
goes," he told me, looking out at the GBR. "The entire food chain is in
big trouble."
Miller agreed.
"If we lose the coral, we lose habitat for all the marine life that
depends on it," he said. "We might see ecosystem collapse as we know it."