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Hang down your heads, Aussies and Kiwis in shame!
Australia, or at least the more intelligent parts of the population, seems to be undergoing a slow awakening to climate change and the destruction of its ecosystem just as we enter the runaway phase and it's too late.
The time to talk about this and take action was about 25 years ago.
There as everywhere the Powers-that-be seem to want to keep it all under wraps and have decided that now is the perfect time to sack hundreds of climate scientists and return to Year Zero.
There as everywhere the Powers-that-be seem to want to keep it all under wraps and have decided that now is the perfect time to sack hundreds of climate scientists and return to Year Zero.
Sydney
experiences highs of 28C when average temperature for May is 19.5C,
with warmer weather set to continue for at least a week in many parts
of country
That hot one in the Tasman Sea that no one's talking about is still well-and-truly there
18
May, 2016
Your
memory is not playing tricks on you – it has been unusually warm
across much of eastern Australia this May.
The
Bureau of Meteorology said temperatures had been “definitely well
above average” across most of the eastern states so far this month.
The
high for Sydney was 28C on Tuesday when the average temperature for
May is 19.5C.
Duty
forecaster Philip Landvogt said it was a similar story for “pretty
much all of the eastern states”.
“All
the way from Brisbane down to even Hobart is warmer than average for
this part of year.”
In
Brisbane the average high temperature for May is 23.2C – and so far
this month not a day has fell below 24C. The city can expect
temperatures in the mid-to-high 20s “well into next week”.
Canberra
has also been warmer than the average May, with an average high of
18.9C so far this month compared with the usual 15.6C.
And
the effect has been felt as far south as Melbourne, where this month
it has been 20.3C while the average May day peaks at 16. 7C.
The
cause was warm ocean temperatures off the east coast and over
northern Australia and prevailing winds bringing warm air from over
the central part of the country to the eastern states.
“The
combination of those two factors has been the reason we’ve had
these warm temperatures,” said Landvogt.
Landvogt
said the warmer weather was set to continue for at least a week in
many parts of Australia.
A
high of 25C for Sydney on Wednesday was forecast to be followed by at
least seven days of temperatures in the region of early to mid-20s –
all well above the May average of 19.5C.
Tasmania
and Melbourne would start to cool down early next week, with the
arrival of a cold front in the coming days.
The
warm water temperatures off the east coast of Australia and dry
conditions over much of the country that were associated with El Niño
were continuing but Landvogt said that system would start to break
down soon.
Sea
surface temperatures across the tropical Pacific Ocean have cooled in
the past fortnight as El Niño draws closer to an end.
Landvogt
said there was a “50-50 chance” of a La Niña weather pattern
forming with the onset of winter. That could lead to more rainfall
over the winter through northern, central and eastern Australia.
The
unseasonal weather follows confirmation of the hottest April on
record globally – and the seventh consecutive month to have broken
global temperature records.
The
latest figures, released by Nasa over the weekend, smashed the
previous record for April by the largest margin ever recorded,
setting 2016 up to be the hottest year ever.
The Sydney Morning Herald is also starting to talk about climate change about 30 years too late. The horse has bolted and it is pointless to to have discussions about closing the gate.
When
should we worry about climate change?
18
May, 2016
News that Tasmania's Cape Grim weather site had recorded its first baseline reading of 400 parts per million of carbon dioxide sparked some debate over the meaning of the milestone.
As we noted ahead of the declaration of the first recording of 400ppm in the southern hemisphere, the primary greenhouse gas increase carried not much more global warming significance than, say, 399 or 401 ppm.
But as with other markers - such as Australia's foreign debt passing a $1 trillion - the 400 ppm tally helps focus our attention.
Smoke rises from Canadian wildfires burning near Fort McMurray, Alberta as the fire season started a month early this year. Photo: Darryl Dyck, Bloombeg
"People react to these things when they see thresholds crossed," David Etheridge, a CSIRO principal research scientist, told us. Even more upbeat was Paul Fraser, the CSIRO scientist who had helped set up Cape Grim 40 years ago. He told 9news.com.au that passing the landmark would be a "psychological tipping point".
Other warning signs - such as the 1 degree warming point reached last year - did at least spur nations to agree at the Paris Climate Summit that temperature increases should be limited to 1.5-2 degrees, even if national policies made 3 degrees more likely.
And so, with CO2 concentrations marching past 400 ppm, when should we start worrying about global warming?
No sign of a cooling off in global temperatures. Photo: Peter Rae
"About 30 years ago," is the blunt answer from David Karoly, a climate scientist with Melbourne University. That's when CSIRO and other scientists declared we had a problem.
"But we shouldn't give up, either," he told me this week. "The worry - and the [climate] action - should now be increased."
During the three decades since, we have poured trillions of dollars into fossil fuel extraction, refining and consumption and a much smaller sum into renewable energy that will have to replace coal, oil and gas - and soon.
As much 60 per cent of the corals at the northern end of the Great Barrier Reef may have died in the current bleaching event. Photo: Eddie Jim
Yet clean energy technologies continue to make rapid advances, including the latest breakthrough at the University of NSW lifting solar efficiency levels to above 34 per cent.
Worries mount
When it comes to extreme weather, there's certainly been a lot to be concerned about in 2016.
Each of the last 12 months is now the hottest on record for that month, with April adding the recent string of beating-by-biggest-margin months.
(See NASA's chart showing temperatures were 1.11 degrees warmer than the 1951-80 average, with large areas in the north particularly warm, while Australia had its second-warmest April.)
Among the climate-related threats, Canada's forest fire season started about a month early. One huge blaze near Alberta's tar sands forced the evacuation of about 88,000 people from the city of Fort McMurray.
The monster El Nino, riding on top of about one degree of background warming, has triggered widespread bleaching of the corals around the world, including our cherished - but apparently expendable - Great Barrier Reef.
More than half the corals in the largely pristine northern end are now dying or dead the reef's Marine Park Authority chief Russell Reichelt told the Senate earlier this month.
On the plus side
However, a dose of of warming can be welcomed where it take off the chill - as in parts of the US - or in Sydney, where summer feels like never lost of its grip even with winter just weeks away.
And all that extra CO2 is leading to a "greening" of the planet with about one-quarter of humans' carbon emissions being taken up by plants, a recent Nature paper found.
But many other changes are far from benign - at least according to the preservation of many existing eco-systems.
Less glamorous than corals, the kelp forests off eastern Tasmania are being destroyed by warm water species swept south by the strengthening and warming East Australian Current. Similarly, the massive dieback of mangrove forest in the Gulf of Carpentaria apparently linked to extreme weather got scant national media coverage.
And, as for the high Arctic where the remarkably prolonged above-average temperatures have led to record-low levels of sea ice, changes are likely to be further from our daily minds.
But less sea ice means less light reflected back to space and more heat absorbed by the oceans - and so the cycle builds and so should our concern.
Spiral warning
In case you missed it, Ed Hawkins, a climate scientist at the UK's University of Reading, came up with the illustration below to help us appreciate the spiralling warming trend since the middle of the 19th century.
By that gauge, when the temperature increase breaks past the 1.5 degrees warming - perhaps in coming months before the El Nino in the Pacific fully stops giving back heat to the atmosphere - will be sufficiently concerned then to act?
Climate scientists, such as Professor Karoly, know globally warming limits agreed at international summits to prevent dangerous climate change - such as 1.5-2 degrees range agreed in Paris - are arbitrary in a similar way to 400 ppm.
"You'd be hard-pressed to find scientists agreeing that 1.5 degrees would be manageable for our reef," he said. "Look at what's happening to the reef this year - and that's with 1 degree warming."
Recent work by his team has identified that on current temperature and carbon emissions trends, the Great Barrier Reef will be hit by bleaching events every second year by 2035.
Other eco-systems, such as alpine ones, are also being affected as species shielded from predators by cool temperatures have literally nowhere to hide.
Big one to worry about
Natural fluctuations mean temperature spikes such as we have seen over the past year can recede - at least partly.
As this year's El Nino in the Pacific lurches towards becoming a La Nina - when equatorial winds turn back to be mostly west-ward blowing and strengthen - we can expect the run of record temperature reading to be broken.
However with greenhouse gas concentrations still rising, the heat we are trapping in the Earth's biosphere - the land, air and sea - will keep on increasing.
And for those climate sceptics who thought the first decade of the 21st century marked a slowdown in temperature increases - the so-called "warming hiatus" - their case for holding off carbon emission cuts is about to get harder to make.
As Fairfax Media noted back in late 2014, a long-lived climate phenomenon named the Pacific Decadal Oscillation, has begun to switch to its positive phase. In fact, climate experts have in the past few days detected it hitting a new high.
"You're playing catch up - now the natural factors want to make the planet warmer," David Jones, head of climate analysis with the Bureau of Meteorology, said.
"Historically when you've had a positive PDO, global temperatures are higher and the rate of warming tends to be quicker."
Some scientists view PDOs as a slower version on the El Nino pattern that forms in the Pacific every three to seven years. Others see it as a separate phenomenon.
"In reality, it's probably a bit of both," Dr Jones said.
Such a PDO switch - it is an 11-year rolling average - would indicate oceans will become less of a sink for the planet's surplus heat - and may even give more of it back to the atmosphere.
That means global conditions will favour more El Nino events but also when La Ninas come, they will tend to be more extreme.
In other words, we could soon have a lot more to worry about.
Back to Year Zero.
The response of my friend Kristy Lewis who is involved in climate research is:
"What southern hemisphere research? Doesn’t exist in cliamte change unless you can put a case forward that involves making money. Most climate reseachers in Australia have gone overseas. Those that are left are sunsisting in teaching positions."
Australian climate job cuts leave hole in Southern Hemisphere research
Details
of redundancies at CSIRO alarm global climate community.
Dani Lewis
18 May, 2016
Staff at the Commonwealth Scientific and Industrial Research Organisation (CSIRO), which employs thousands of scientists across Australia, were told over the past week where long-awaited job cuts in climate science are likely to fail.
Many CSIRO researchers who spoke toNature about
the lay-offs requested anonymity so as not to breach the
organization's communications policy, which tells researchers not to
discuss funding or management decisions. But the information that is
trickling out means that scientists are already evaluating the likely
impact on research – although a consultation process means that it
may be months before an expected 140 lay-offs in climate research are
complete.
“It’s
significant beyond the numbers because of our overall uniqueness,”
says oceanographer Peter Craig, who worked for CSIRO for 30 years but
retired from the agency at the end of March. “The rest of the world
does rely on us for both measurements and interpretation of what’s
going on on this side of the world.”
Ice lab threatened
CSIRO
scientists in Melbourne who analyse ice cores from an ice cap called
Law Dome in Antarctica – a group colloquially known as the ‘Ice
Lab’ – fear their programme is one that might be curtailed.
Because
the Law Dome accumulates ice very rapidly and traps low levels of
impurities as it grows, its cores constitute the most reliable record
of greenhouse-gas emissions over the past 2,000 years, says Malte
Meinshausen, a climate modeller at the University of Melbourne and
the Potsdam Institute for Climate Impact Research in Germany. Climate
models that predict how many degrees of warming will occur under
different greenhouse-gas emissions scenarios rely heavily on its
record, Meinshausen says.
David
Etheridge, head of ice core research, says that he has not been told
he will lose his job, but that other scientists who do ice core
analysis are facing redundancy. CSIRO has said that the Ice Lab will
remain open, but Etheridge believes that cuts will have negative
consequences for palaeo-climate research and the climate models that
rely on it.
Aerosol fear
CSIRO
researchers also fear that Australia’s contributions to the world’s
largest ground-based network of aerosol sensors, called AERONET — a
NASA-led project to verify the sometimes ambiguous aerosol
measurements made by satellite — are in jeopardy. On 1 May, Brent
Holben, who leads the AERONET project in Greenbelt, Maryland, wrote
to CSIRO to urge that it reconsider its cuts.
He said that they would
cause the loss of aerosol measurements over a large region of the
Southern Hemisphere.
Asked
for a statement, the agency said: “CSIRO is working with partners
to identify the most efficient way of delivering this work.”
Sea-level expertise
Notable
among individual staff set to lose their jobs is John Church, an
expert on sea-level rise who has worked for CSIRO for 38 years and
who coordinated a chapter on sea-level change for the most recent
assessment report of the Intergovernmental Panel on Climate Change
(IPCC), released in 2014.
Church
was at sea on the research vessel RV Investigator when
he learnt last week that, as he had expected, he would be made
redundant.
“John
has probably done more to lay a really firm scientific foundation
under the issue of sea-level rise than anyone else in the world,”
says Steve Rintoul, a fellow oceanographer at the CSIRO. “The
signal that this sends to both staff within and outside of CSIRO is
really horrible.”
The
RV Investigator’s
voyage from the Southern Ocean to the Equator is currently mapping
deep-ocean temperature and chemistry under the international GO-SHIP
program, and is also deploying Argo
and biogeochemistry floats that
gather data at the ocean surface. CSIRO says that neither the
frequency of the ship’s expeditions nor the associated data
analysis will be adversely affected. But researchers who did not want
to be named said that, with the cuts, they doubted that such
extensive surveys would be possible in the future, or that other
Australian agencies could fill the gaps in expertise if oceanography
groups were disbanded.
CSIRO.
CC-BY-3.0 Layoffs
in CSIRO's oceanography groups may dampen the productivity of the
Australian research vessel RV Investigator.
CSIRO
had first
announced in February that
it planned to shed hundreds of jobs as part of a strategic shift away
from basic climate science; in April, it confirmed that
this included almost 140 lay-offs in its ‘Oceans and Atmosphere’
and ‘Land and Water’ divisions.
The
CSIRO cuts are “inexplicable”, says Thomas Stocker at the
University of Berne, who co-chaired the IPCC’s Working Group I
(which examines the physical science of climate change) between 2008
and 2015. He is particularly concerned about the cuts to the
sea-level research group. “It’s simply not understandable for me
that the stewards of a country that is so fundamentally exposed to
sea-level rise is able to basically terminate research activity in
their own country,” he says.
Negotiations
since February have staved off cuts in some programmes, says one
senior scientist at CSIRO’s Aspendale site in Melbourne. For
example, CSIRO ratcheted back cuts for a team that analyses air
pollution from data drawn from the remote Cape Grim Observatory in
Tasmania, so that Australia could continue to meet obligations to
international agreements such as the Montreal Protocol, which
governments signed in 1987 to protect the stratospheric ozone layer
from damage by chlorofluorocarbons.
But
it seems that the bulk of the cuts will not be reversed. Although
more than 3,000 scientists have urged Australian politicians and
CSIRO management in an open letter to reconsider the proposed
lay-offs, the government has distanced itself, saying that they are
an agency-level decision. With national elections set for 2 July, the
opposing Labor party has said that if it were elected, it would
direct the CSIRO's board to stop the lay-offs. However, it would not
reappoint scientists who accept redundancies before then
Mangrove Ecosystems In Queensland Are Dying Just Like The Great Barrier Reef
17
May, 2016
Australia
is still recovering from the massive coral bleaching in the Great
Barrier Reef, however, its ecosystem gets another blow — the
Mangrove population in Queensland is dying.
Scientists
are yet to establish an explanation of what could have caused it, but
they are certain that the damage covers a large area.
The
hot climate coinciding with the dry period of Northern Australia
could have triggered the widespread deaths, because there is no other
major event, such as cyclone, tsunami or oil spill in the area that
could have resulted in such destruction of the mangrove ecosystem,
said Norm Duke, a professor from James Cook University and a
spokesman for the Australian Mangrove and Saltmarsh Network (AMSN).
Ecosystem
At Risk
Mangroves
are crucial because they minimize the erosion of shorelines and
prevent sediment from going offshore, thus, filtering the inland
water before it enters the sea. Without the mangroves, coastal
ecosystem like seagrass and corals could vanish as well.
These
mangroves also serve as fish sanctuaries. Fishermen have already
reported about meager catches along with the diminishing mangrove
ecosystem.
Because
of their extensive root network, mangroves can store and trap carbon
five times more than the normal forest. When they are lost, Duke
explained, the carbon would be released into the atmosphere and might
intensify global warming.
Close
Monitoring Needed
AMSN
officials cannot closely monitor such an expansive damaged area
because they do not have the funding to do so. They only rely on
information from the locals and imaging from Google Earth.
Australia
has 7 percent of the world's mangrove population, and Duke fears that
if the numbers continue to decline, the ecosystem will be
significantly disrupted.
"Once
the trees have died, they can only grow back from seedling which may
take 20 to 30 years before you get a functioning forest again,"
said Duke.
Initial
observations of the mangrove dieback were presented during the AMSN
Conference. Duke said that monitoring efforts should be carried out
to establish a baseline condition of the shorelines.
The
mangroves in the Indo-Pacific are also being threatened to become
extinct by 2070 because of rising sea levels.
While
scientists are still figuring out the exact cause of the mangrove
deaths, it seems that climate change could be the one to blame.
Just in case you have been way on Mars and weren't already aware of this....
A Death of Beauty — Climate Change is Bleaching the Great Barrier Reef Out of Existence
21
April, 2016
Extinction.
It’s
a hard, tough thing to consider. One of those possibilities people
justifiably do not want to talk about. This notion that a creature
we’re fond of and familiar with — a glorious living being along
with all its near and distant relatives — could be entirely removed
from the web of existence here on Earth.
Our
aversion to the topic likely stems from our own fear of death. Or
worse — the notion that the entire human race might eventually be
faced with such an end. But extinction is a threat that we’ll see
arising more and more as we force the world to rapidly warm. For
species of the world now face existential crisis with increasing
frequency as atmospheric and ocean temperatures have risen so fast
that a growing number of them have simply become unable to cope with
the heat.
The
Great Barrier Reef of Australia — the world’s largest single
structure made up of living organisms — is no exception. For this
1,440 mile long expanse of corals composed of more than 2,900
individual reefs that has existed in one form or another for
600,000 years has
suffered a severe blow —
one from which it may never be able to recover. One that appears
likely to kill up to 90 percent of its corals along previously
pristine regions in its northern half.
(Governments
failed to listen to the warnings of scientists like Terry Hughes.
Now, it appears that the Great Barrier Reef has been hit by a blow
from coral bleaching from which it may never be able to recover.
Video source: Australian
Broadcasting on the Great Barrier Reef’s Worst Coral Bleaching
Event on Record.)
The
damage comes in the form of extreme ocean heat. Heat resulting from
global temperatures that are now well in excess of 1 degree C above
preindustrial times. Heat that has forced ocean temperature
variability into a range that is now lethal for certain forms of sea
life. Particularly for the world’s corals which are now suffering
and dying through the worst global bleaching event ever experienced.
The
Worst Global Coral Bleaching Event Ever Experienced
During
2014 the oceans began to heat up into never-before seen temperature
ranges. This warming initiated a global coral bleaching event that
worsened throughout 2015. By early 2016 global surface temperatures
rocketed to about 1.5 C above 1880s averages for the months of
February and March. These new record high temperatures came on the
back of annual carbon emissions now in the range of 13 billion tons
each year and at the hotter end of the global natural variability
cycle called El Nino. Both the atmosphere near the land surface and
the upper levels of the ocean experienced this extreme warming.
In
the ocean, corals rely on symbiotic microbes to aid in the production
of energy for their cellular bodies. These microbes are what give the
corals their wild arrays of varied and brilliant colors. But if water
temperatures rise high enough, the symbiotic microbes that the corals
rely on begin to produce substances that are toxic to the corals. At
this point, the corals expel the microbes and lose their brilliant
coloration — reverting to a stark white.
(A
vast region of the world’s ocean system continues to experience
coral bleaching. In area, extent, height of extreme temperature, and
duration, the current global coral bleaching event is the worst ever
experienced by a good margin. As global temperatures continue to warm
due to ongoing fossil fuel burning and related carbon emissions,
widespread coral bleaching is likely to become an annual occurrence.
Temperatures have risen far enough and will continue to rise for long
enough to set about ocean conditions that will result in mass coral
die-offs around the world. Image source: NOAA.)
Bleaching
isn’t necessarily lethal to corals. However, once the microbes are
gone, the corals have lost a key energy source and will eventually
die without them. If ocean temperatures return to normal soon enough,
the corals can begin to accept the symbiotic microbes back, return to
a healthy cellular energy production, and survive — albeit in a
weakened and more vulnerable state for some time to come. But if
ocean temperatures remain too warm for an extended period, then the
corals will be deprived of energy and nutrients for too long and they
will inevitably perish.
The
kind of coral bleaching event that we’re experiencing now is a mass
killer of corals. Not simply due to the heat itself, but due to the
long duration of the extreme temperature spike. By late February,
many ocean scientists were very concerned about the already severe
damage reports that were starting to come in. At
that time, NOAA issued this warning:
“We are currently experiencing the longest global coral bleaching event ever observed. We may be looking at a 2- to 2½-year-long event. Some areas have already seen bleaching two years in a row.”
93
Percent of Great Barrier Reef Affected by Bleaching
By
late February, the level of concern for the Great Barrier Reef was
palpable. Stark reports were starting to come in from places like
Fiji — which had experienced two years of severe bleaching — and
Christmas Atoll about 1,300 miles south of Hawaii — whose
reported losses were best described as staggering.
So far, the worst of the hot water had stayed away from Australia’s
great reef.
But
by early March a plume of very extreme ocean heat began to appear
over The Great Barrier Reef’s northern sections. Sea surface
temperatures spiked to well above, a dangerous to corals, 30 degrees
Celsius for days and weeks. This 30 C or greater heat extended deep —
hitting as far as 50 meters below the ocean surface over the reef.
And it rippled southward — hitting section after section until few
parts of the reef were spared.
Terry
Hughes, one of the world’s foremost experts on the Great Barrier
Reef, on
March 18th tweeted his fear and anguish over the situation:
At
this point, there was no stopping the tragedy. Fossil fuel emissions
had already warmed the airs and waters to levels deadly to the living
reef. It was all researchers could do to work frantically to assess
the damage. Teams of the world’s top reef scientists swept out —
performing an extensive survey of the losses. More than 911 reef
systems were assessed and, in total, the
teams found that fully 93 percent of the Great Barrier Reef system
had experienced some level of bleaching.
Final
Death Toll for Some Sections Likely to Exceed 90 Percent
In
extent, this was the worst bleaching event for the Great Barrier Reef
by a long shot. Back during the previous most severe bleaching events
of 1998 and 2002, 42
percent and 54 percent of the reef was affected.
By any measure, the greatly expanded 2016 damage was catastrophic.
“We’ve never seen anything like this scale of bleaching before.
In the northern Great Barrier Reef, it’s like 10 cyclones have come
ashore all at once,”said Professor
Terry Hughes in the ARC coral bleaching report.
Out
of all the reefs surveyed in the report, just 7% escaped bleaching.
Most of these reefs occupied the southern section — a region that
was spared the worst of the current bleaching event due to cooler
water upwelling provided by the powerful winds of Hurricane Winston.
But impacts to the Northern section of the reef could best be
described as stark. There,
a section composing almost the entire northern half of the reef saw
between 60 and 100% of corals experiencing severe bleaching.
In the reports, Hughes notes that many of these corals are not likely
to survive. In the hardest hit reefs — which were in the most
remote sections least affected by Australia’s industrial run-off —
algae has been observed growing over 50 percent of the corals
affected — an
indication that these corals are already dead:
“Tragically, this is the most remote part of the Reef, and its remoteness has protected it from most human pressures: but not climate change. North of Port Douglas, we’re already measuring an average of close to 50% mortality of bleached corals. At some reefs, the final death toll is likely to exceed 90%. When bleaching is this severe it affects almost all coral species, including old, slow-growing corals that once lost will take decades or longer to return (Emphasis added).”
But
with the oceans still warming, and with more and still worse coral
bleaching events almost certainly on the way, the question has to be
asked — will these corals ever be afforded the opportunity to
recover?
A
Context of Catastrophe with Worse Still to Come
As
ocean surface temperatures are now entering a range of 1 C or more
above 1880s levels, corals are expected to experience bleaching with
greater and greater frequency. The Intergovernmental Panel on Climate
Change in 2007 identified
the time-frame of 2012 to 2040 as a period of rising and extreme risk
to corals due to bleaching.
IPCC also identified bleaching as the greatest threat to corals and
related reef-dependent sea life.
When
ocean surface temperatures warm into a range of 2 C above 1880s
levels — the kind of severe global heating that could arise under
worst-case fossil fuel emissions and related warming scenarios by the
mid 2030s — corals in the Great Barrier Reef are expected to
experience bleaching on an annual basis. Every year, in other words,
would be a mass coral bleaching and die-off year.
(Sea
surface temperatures and temperatures withing the top 50 meters of
water over the Great Barrier Reef of Australia rose to 3-4 C above
average during the austral Summer and Fall of 2016. These record
temperatures lasted for weeks in some regions setting off the worst
coral bleaching event the Great Barrier Reef has ever seen. By
mid-Century, coral bleaching and mass die-offs are likely to occur on
an annual basis as global temperatures surpass the 1.5 C and 2 C
thresholds. Image source: Earth
Nullschool.)
Globally,
bleaching events under even moderate fossil fuel emissions scenarios
would tend to take up much of the Equatorial region on an annual
basis by mid-Century. Events that can, during single years, wipe out
between 90 and 95 percent of corals at any given location. A handful
of corals will likely survive these events — representing a remote
and far-flung remnant who were simply a bit hardier, or lucky, or who
had developed an ability to accept microbes that are tolerant to
warmer temperatures. But these hardy or fortunate few would take
hundreds to thousands of years to re-establish previous coral reef
vitality even if other harmful ocean conditions did not arrive to
provide still more damage.
As
coral bleaching expands at the Equator due to increasing rates of
ocean warming, increasing levels of carbon dioxide in the atmosphere
causes oceans to become more acidic. Cooler waters at the poles are
better able to transfer gasses into the ocean’s waters. And higher
levels of carbon dioxide in the world ocean results in a growing
acidity that is harmful to corals. Increasing levels of ocean acidity
thus creep down from the poles at the same time that bleaching events
move up from the Equator.
If
fossil fuel emissions continue, by mid-Century atmospheric carbon
dioxide levels in the range of 450 to 500 parts per million will have
provided a never-before seen spike to ocean acidity. Such high ocean
acidity would then provide a second severe blow to corals already
devastated by bleaching events. It’s a 1-2 punch that represents a
mass extinction threat for corals this Century. And we’re starting
to see the severe impacts ramp up now.
(Coral
bleaching is a severe threat to tropical coral reefs now. But CO2
potentially hitting above 500 parts per million, according to a 2014
study, risks a complete loss of equatorial coral reefs by 2050 to
2100. Between bleaching and acidification, there’s no way out for
corals so long as fossil fuel burning continues. Image source: Threat
to Coral Reefs From Ocean Acidification.)
The
only hope for stopping this ever-expanding harm is a rapid cessation
of fossil fuel emissions. And we owe it to the corals of the world,
the millions of species that depend on them, and the hundreds of
millions of people whose food sources and economic well being come
from the corals.
“And
Then We Wept”
When
researchers told students of the extent of harm to corals upon the
Great Barrier Reef,the
students were reported to have wept.
And with good reason. For our Earth had just experienced a profound
death of beauty. A death of a vital and wondrous living treasure of
our world. A priceless liquid gem of our Earth. A wonder that gives
life to millions of species and one that grants both food and
vitality to Australia herself. For if the reef goes, so does a huge
portion of the living wealth of that Nation and our world.
Sadly,
the tears will just keep coming and coming as these kinds of events
are bound to worsen without the most dramatic and urgent global
actions. The current and most recent catastrophe is thus yet one more
in a litany of wake up calls to the world. But will we hear it loud
and clear enough to act in ways that are necessary to ensure the
corals survival? And what of the billions of creatures and of the
millions of humans too that depend on the corals? Do we care about
them enough to act?
Links:
Hat
tip to Caroline
Hat
tip to Spike
Hat
tip to Colorado Bob
Hat
tip to Ryan in New England
Hat
tip to Griffon
(Please
support public, non-special interest based science like the essential
work that has been provided by Terry Hughes over so many years and
decades. Scientists like Terry provide a vital public service. For
years, they have given us a clear warning of a very real and ever
more present danger. A warning that gives us a fleeting opportunity
to respond to events before we lose the richest living treasures of
our world. Before we are bereft of our ability to continue to make
livelihoods as environmental abundance and the related regional and
global life support systems are irreparably damaged.)
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