'Dead Corals Don't Make Babies': Great Barrier Reef Losing Its Ability To Recover From Bleaching (cnn.com)
An anonymous reader quotes a report from CNN: Successive ocean heat waves are not only damaging Australia's Great Barrier Reef, they are compromising its ability to recover, raising the risk of "widespread ecological collapse," a new study has found. The 2,300-kilometer-long (1,500 mile) reef has endured multiple large-scale "bleaching" events caused by above-average water temperatures in the last two decades, including back-to-back occurrences in 2016 and 2017.
The new study, released Wednesday in the journal Nature, examined the number of adult corals which survived these two events and how many new corals they created to replenish the reef in 2018.
The answer was as bleak as it was stark: "Dead corals don't make babies," the study's lead author, Terry Hughes, said in a press release. Scientists working on the study found the loss in adult corals caused a "crash in coral replenishment" on the reef, as heat stresses brought about by warming ocean temperatures impacted the ability of coral to heal. "The number of new corals settling on the Great Barrier Reef declined by 89% following the unprecedented loss of adult corals from global warming in 2016 and 2017," said Hughes. Scientists working on the report say they would expect coral recruitment to recover over the next 5 to 10 years, as more corals reach sexual maturity, but only in the absence of another bleaching event. However, with sea temperatures continuing to rise this seems a near-impossiblity.
The answer was as bleak as it was stark: "Dead corals don't make babies," the study's lead author, Terry Hughes, said in a press release. Scientists working on the study found the loss in adult corals caused a "crash in coral replenishment" on the reef, as heat stresses brought about by warming ocean temperatures impacted the ability of coral to heal. "The number of new corals settling on the Great Barrier Reef declined by 89% following the unprecedented loss of adult corals from global warming in 2016 and 2017," said Hughes. Scientists working on the report say they would expect coral recruitment to recover over the next 5 to 10 years, as more corals reach sexual maturity, but only in the absence of another bleaching event. However, with sea temperatures continuing to rise this seems a near-impossiblity.
Please enlighten everyone about what happened to the corals in the Great Barrier Reed during the Medieval Warm Period. It was quite warm then, too, yet we still have plenty of corals today.
Oh, wait, we're not supposed to talk about that... I almost forgot.
- snruter rotsac
" if you got your stories straight. " = Yes, every scientist in the world needs to get their data to align in marching lock step, like Fox News does. There has to be a choral unison of agreement, in all niches. Great point, moron.
Well, 500 million might be a bit too much, but yes. Temperatures leaves traceable changes.
For example clam shells have temperature dependent rings much like trees.
So by digging up and comparing clam shells from a specific time you can get a rough idea of temperature changes.
But there are thousands of different ways so it is a lot of work to get accurate temperature estimations.