Wednesday, November 30, 2016
Another shriek about bleaching on the Great Barrier Reef
This is just a repetition of a story that has been going on for a year or more. Previous claims of this nature have been shown to be highly exaggerated so a repetition of the claims from the same people as before has no credibility.
I was born and bred in an area close to the reef and have been hearing cries of alarm about the reef for 50 years. But somehow the reef still seems to be there. It has always had episodes of retreat but coral is highly resilient and bounces back quite rapidly.
One thing we can be sure of is that the problems were not caused by anthropogenic global warming. Why? Because that theory says that warming is caused by increased levels of CO2 in the atmosphere. But the latest readings show NO increase in CO2 during 2015 and 2016
There WAS warming up until recently but that was caused by the El Nino weather cycle, not CO2. Once again we had the chronic Warmist problem that CO2 levels and temperatures do not correlate. Below is a picture of the El Nino effect on global temperatures. You see it peaked late last year and has been falling ever since. So if warmth was the cause of the reef problems, the reef should soon start to recover
Two-thirds of the corals in the northern part of the Great Barrier Reef have died in the reef’s worst-ever bleaching event, according to our latest underwater surveys.
On some reefs in the north, nearly all the corals have died. However the impact of bleaching eases as we move south, and reefs in the central and southern regions (around Cairns and Townsville and southwards) were much less affected, and are now recovering.
In 2015 and 2016, the hottest years on record, we have witnessed at first hand the threat posed by human-caused climate change to the world’s coral reefs.
Heat stress from record high summer temperatures damages the microscopic algae (zooxanthellae) that live in the tissues of corals, turning them white.
After they bleach, these stressed corals either slowly regain their zooxanthellae and colour as temperatures cool off, or else they die.
The Great Barrier Reef bleached severely for the first time in 1998, then in 2002, and now again in 2016. This year’s event was more extreme than the two previous mass bleachings.
Surveying the damage
We undertook extensive underwater surveys at the peak of bleaching in March and April, and again at the same sites in October and November. In the northern third of the Great Barrier Reef, we recorded an average (median) loss of 67% of coral cover on a large sample of 60 reefs.
The dieback of corals due to bleaching in just 8-9 months is the largest loss ever recorded for the Great Barrier Reef.
To put these losses in context, over the 27 years from 1985 to 2012, scientists from the Australian Institute of Marine Science measured the gradual loss of 51% of corals on the central and southern regions of the Great Barrier Reef.
They reported no change over this extended period in the amount of corals in the remote, northern region. Unfortunately, most of the losses in 2016 have occurred in this northern, most pristine part of the Great Barrier Reef.
The bleaching, and subsequent loss of corals, is very patchy. Our map shows clearly that coral death varies enormously from north to south along the 2,300km length of the Reef.
The southern third of the Reef did not experience severe heat stress in February and March. Consequently, only minor bleaching occurred, and we found no significant mortality in the south since then.
In the central section of the Reef, we measured widespread but moderate bleaching, which was comparably severe to the 1998 and 2002 events. On average, only 6% of coral cover was lost in the central region in 2016.
The remaining corals have now regained their vibrant colour. Many central reefs are in good condition, and they continue to recover from Severe Tropical Cyclones Hamish (in 2009) and Yasi (2011).
In the eastern Torres Strait and outermost ribbon reefs in the northernmost part of the Great Barrier Reef Marine Park, we found a large swathe of reefs that escaped the most severe bleaching and mortality, compared to elsewhere in the north. Nonetheless, 26% of the shallow-water corals died.
We suspect that these reefs were partially protected from heat stress by strong currents and upwelling of cooler water across the edge of the continental shelf that slopes steeply into the Coral Sea.
For visitors, these surveys show there are still many reefs throughout the Marine Park that have abundant living coral, particularly in popular tourism locations in the central and southern regions, such as the Whitsundays and Cairns.
Darkspots
The northern third of the Great Barrier Reef, extending 700km from Port Douglas to Papua New Guinea, experienced the most severe bleaching and subsequent loss of corals.
On 25% of the worst affected reefs (the top quartile), losses of corals ranged from 83-99%. When mortality is this high, it affects even tougher species that normally survive bleaching.
However, even in this region, there are some silver linings. Bleaching and mortality decline with depth, and some sites and reefs had much better than average survival. A few corals are still bleached or mottled, particularly in the north, but the vast majority of survivors have regained their colour.
What will happen next?
The reef science and management community will continue to gather data on the bleaching event as it slowly unfolds. The initial stage focused on mapping the footprint of the event, and now we are analysing how many bleached corals died or recovered over the past 8-9 months.
Over the coming months and for the next year or two we expect to see longer-term impacts on northern corals, including higher levels of disease, slower growth rates and lower rates of reproduction. The process of recovery in the north – the replacement of dead corals by new ones – will be slow, at least 10-15 years, as long as local conditions such as water quality remain conducive to recovery.
As global temperatures continue to climb, time will tell how much recovery in the north is possible before a fourth mass bleaching event occurs.
SOURCE
Monday, November 28, 2016
Australian anti-immigration politician slips into wetsuit for barrier reef trip -- and finds that all is well with the reef
Most of the media have been amusing about this. They say that she has embarrassed herself by not going to the "right" part of the reef. But that claim is itself a message that only part of the reef is affected by bleaching. We can perhaps be thankful to them for getting that message out to a wider audience.
There are many possible causes of bleaching but the loons of the Green/Left are sure it is caused by global warming. And that might pass muster when we note that the bleaching has occurred in the most Northerly (and hence warmer) one-third of the reef. Problem: Coral LIKES warmth, which is why the Northern part of the reef normally has the greatest biological diversity. Normally, the further North you go (i.e. the warmer you get), the greater the diversity. So the cause of the bleaching is unknown.
As a fallback position, the Greenies say that the bleaching is caused by agricultural runoff. Problem: The Northern part of the reef runs along an area of the Cape York Peninsula where there is virtually NO agriculture. The soils there are too poor for it to be economically feasible. So no runoff. "Facts be damned" seems to be the Greenie motto
Pauline Hanson has slipped into a wetsuit and made a splash on the Great Barrier Reef to show the world the natural wonder is worth visiting amid claims it is dying.
The senator, who once cooked fish for a living, went swimming off Great Keppel Island today and expressed concerns about reports on the reef's health.
Ms Hanson says agenda-driven groups are telling "untruths" about the state of the reef that are harming the tourism industry and businesses. "When we have these agendas that are actually destroying our tourism industry and businesses ... we need to ask the questions and we want answers," she said. "The Greens have no concern about people and jobs that we need here in Queensland, and the escalating costs that we are feeling from the effects of this."
One Nation senators Malcolm Roberts, who has long argued the case that global warming doesn't stack up, and Brian Burston were also on the reef trip.
Mr Roberts said people had stopped coming to the reef because they were being told it was dead and that Australia should not be reporting on its health to the UN agency UNESCO.
Conservationists are concerned climate change is putting severe stress on the reef, which experienced a massive coral bleaching event this year, and some have declared it's dying at an unprecedented rate.
They say Ms Hanson and her senators visited the wrong part of the reef as the southern sections had been least affected by the worst bleaching event in the icon's history.
The World Wildlife Fund said One Nation should have visited Lizard Island where bleaching, caused by high water temperatures, has killed much of the coral.
SOURCE
Sunday, November 13, 2016
Why the death of coral reefs could be devastating for millions of humans
It certainly would be detrimental, though well within the human capacity to adapt. But will it happen? Coral recovers quickly from bleaching and at Bikini atoll it even survived a thermonuclear hit on it! If an H-bomb didn't kill it off, what would? Coral reefs have been around for millions of years and in some cases are today right where they always were.
They are however surrounded by Green/Left lies. Australian Greenies claim that reef damage is caused by agricultural runoff. Problem: The current bleaching event on the Great Barrier Reef is on its Northern third, along the coast of the Cape York Peninsula -- and there are virtually no farms there. Isn't reality pesky?
Coral does undergo bleaching from time to time in response to various stressors but bleaching is a defence mechanism, not death.
And even the first sentence below is a laugh. Oceans CANNOT be both warmer and more acidic at the same time. Warmer oceans outgas CO2, which is the alleged cause of the acidity. Just open a warm can of Coke someday if you doubt it. Physicists call it Henry's law. There's no such thing as an honest Greenie as far as I can see. You believe anything they say at your peril
Coral reefs around the globe already are facing unprecedented damage due to warmer and more acidic oceans. It’s not a problem that just affects the marine life that depends on them or deep-sea divers who visit them.
If carbon dioxide emissions continue to fuel the planet’s rising temperature, the widespread loss of coral reefs by 2050 could have devastating consequences for tens of millions of people, according to research published Wednesday in the scientific journal PLOS.
To better understand where those losses would hit hardest, an international group of researchers mapped places where people most need reefs for their livelihoods, particularly for fishing and tourism, as well as for shoreline protection. They combined those maps with others showing where coral reefs are most under stress from warming seas and ocean acidification.
Countries in Southeast Asia such as Indonesia, Thailand, and Philippines would bear the brunt of the damage, the scientists found. So would coastal communities in western Mexico and parts of Australia, Japan, and Saudi Arabia. The problem would affect countries as massive as China and as small as the tiny island nation of Nauru in the South Pacific.
In many places, the loss of coral reefs would amount to an economic disaster, depriving fishermen of their main source of income, forcing people to find more expensive forms of protein, and undermining the tourism industry.
"It means jobs for lots of people," said Linwood Pendleton, the study’s lead author and an international chair at the European Institute of Marine Studies.
In addition, many countries depend on coral reefs as a key barrier to guard against incoming storms and mitigate the damage done by surging seas. Without healthy reefs, "you lose what is essentially a moving, undersea sea wall," said Pendleton, who estimated that about 62 million people live less than 33 feet above sea level and less than two miles from a coral reef. "The waves just come into shore full force. That can cause loss of life. It can cause loss of property."
Some of the countries most dependent on coral reefs are also among the largest polluters.
"Some of the places that have the most to lose . . . are also among the biggest carbon emitters," Pendleton said. "They really have it in their power to bring down the levels of carbon" they emit into the atmosphere.
Other countries that rely heavily on reefs, such as Fiji or Papua New Guinea, have relatively small carbon footprints. Still, Pendleton said they can take other measures — including not overfishing and avoiding pollution — to prevent putting further pressure on already stressed reefs.
The researchers acknowledged more study is needed to better understand both what is happening to coral reefs around the globe and how that will affect humans. But it can be difficult, they noted, because "carrying out science and data collection in many of the coral reef regions most at risk of global environmental change is a challenge." Many regions lack the capacity to do routine data collection, and scientists often have trouble getting permission to sample in coastal areas or where maritime jurisdictions are disputed.
While coral reefs traditionally have been resilient in the face of environmental pressures, mounting evidence suggests their ability to bounce back is limited.
This fall, scientists reported that substantial swaths of the Great Barrier Reef — the world’s largest coral reef system, located off Australia —might have died in the wake of a historic coral-bleaching event.
"The mortality is really devastating," Andrew Hoey, a senior research fellow with the ARC Centre of Excellence for Coral Reef Studies at James Cook University in Queensland, told the Post last month as scientists worked to catalog the damage. "It’s a lot higher than we had hoped."
Earlier This spring, researchers discovered that parts of Florida’s coral reef tract — the largest reef in the continental United States and the third-largest barrier reef ecosystem in the world — are actually dissolving into the water, likely because of the effects of ocean acidification.
Meanwhile, reefs around the US territory of Guam and other nearby islands, in what is known as the Marianas archipelago, have suffered from coral-bleaching events every year since 2013.
And there’s been no sign of a break this summer. After a recent dive in Guam’s Tumon Bay, coral ecologist Laurie Raymundo took to Facebook to describe her shock at the devastation.
"I consider myself to be fairly objective and logical about science," wrote Raymundo, of the University of Guam. "But sometimes that approach fails me. Today, for the first time in the 50 years I’ve been in the water, I cried for an hour, right into my mask, as I witnessed the extent to which our lovely Tumon Bay corals were bleaching and dying."
SOURCE
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