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Is the End in Sight for The World’s Coral Reefs?

7 Dec

It is a difficult idea to fathom. But the science is clear: Unless we change the way we live, the Earth’s coral reefs will be utterly destroyed within our children’s lifetimes.

by j.e.n. veron

Over the past decades, there have dozens of articles in the media describing dire futures for coral reefs. In the 1960s and ‘70s, we were informed that many reefs were being consumed by a voracious coral predator, the crown-of-thorns starfish. In the 1980s and ‘90s, although these starfish still reared their thorny heads from time to time, the principal threats had moved on — to sediment runoff, nutrients, overfishing, and general habitat destruction.

For me, an Australian marine scientist who has spent the past 40 years working on reefs the world over, these threats were of real concern, but their implications were limited in time or in space or both. Although crown-of-thorns starfish can certainly devastate reefs, the impacts of sediments, nutrients and habitat loss have usually been of greater concern, and I have been repeatedly shocked by the destruction I have witnessed. However, nothing comes close to the devastation waiting in the wings at the moment.

Great Barrier Reef

Photo courtesy of J.E.N. Veron
Ribbon reefs have formed the outer edge of the Great Barrier Reef for millions of years.

You may well feel that dire predictions about anything almost always turn out to be exaggerations. You may think there may be something in it to worry about, but it won’t be as bad as doomsayers like me are predicting. This view is understandable given that only a few decades ago I, myself, would have thought it ridiculous to imagine that reefs might have a limited lifespan on Earth as a consequence of human actions. It would have seemed preposterous that, for example, the Great Barrier Reef — the biggest structure ever made by life on Earth — could be mortally threatened by any present or foreseeable environmental change.

Yet here I am today, humbled to have spent the most productive scientific years of my life around the rich wonders of the underwater world, and utterly convinced that they will not be there for our children’s children to enjoy unless we drastically change our priorities and the way we live.

A decade ago, my increasing concern for the plight of reefs in the face of global temperature changes led me to start researching the effects of climate change on reefs, drawing on my experience in reef science, evolution, biodiversity, genetics, and conservation, as well as my profound interests in geology, palaeontology, and oceanography, not to mention the challenging task of understanding the climate science, geochemical processes, and ocean chemistry.

When I started researching my book, A Reef in Time: The Great Barrier Reef from Beginning to End (Harvard, 2008), I knew that climate change was likely to have serious consequences for coral reefs. But the big picture that gradually emerged from my integration of these disparate disciplines left me shocked to the core.

In a long period of deep personal anguish, I turned to specialists in many different fields of science to find anything that might suggest a fault in my own conclusions. But in this quest I was depressingly unsuccessful. The bottom line remains: Science argues that coral reefs can indeed be utterly trashed in the lifetime of today’s children. That certainty is what motivates me to spread this message as clearly, and accurately, as I can.

So what are the issues? Most readers will know that there have been several major episodes of mass bleaching on major reef areas worldwide over the past 20 years. In the late-1980s when the first mass bleaching occurred, there was a great deal of concern among reef scientists and conservation organizations, but the phenomenon had no clear explanation. Since then, the number and frequency of mass bleachings have increased and sparked widespread research efforts.

Corals have an intimate symbiotic relationship with single-celled algae, zooxanthellae, which live in their cells and provide the photosynthetic fuel for them to grow and reefs to form. The research showed that this

‘Ecosystems can recover from all sorts of abuse, and coral reefs are no exception.’

relationship can be surprisingly fragile if corals are exposed to high light conditions at the same time as above-normal water temperatures, because the algae produce toxic levels of oxygen, and excessive levels of oxygen are toxic to most animal life. Under these conditions, corals must expel the zooxanthellae, bleach, and probably die or succumb to the toxin and definitely die. A tough choice, one they have not had to make at any time in their long genetic history.

read more – whole article here

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Scientists fear mass extinction as oceans choke

30 Nov

By Amy Simmons / ABC News

Australian scientists fear the planet is on the brink of another mass extinction as ocean dead zones continue to grow in size and number.

More than 400 ocean dead zones – areas so low in oxygen that sea life cannot survive – have been reported by oceanographers around the world between 2000 and 2008.

That is compared with 300 in the 1990s and 120 in the 1980s.

Professor Ove Hoegh-Guldberg, of the ARC Centre of Excellence for Coral Reef Studies (CoECRS) and from the University of Queensland, says there is growing evidence that declining oxygen levels in the ocean have played a major role in at least four of the planet’s five mass extinctions.

“Until recently the best hypothesis for them was a meteor strike,” he said.

“So 65 million years ago they’ve got very good evidence … all the dinosaurs died because of smoke and stuff in the atmosphere from a meteor strike.

“But with the four other mass extinction events, one of the best explanations now is that these periods were preceded by an increase of volcanic activity, and that volcanic activity caused a change in ocean circulation.

“Just as we are seeing at a smaller scale today, huge parts of the ocean became anoxic at depth.

“The consequence of that is that you had increased amounts of rotten egg gas, hydrogen sulfide, going up into the atmosphere, and that is thought to be what may have caused some of these other extinction events.”

Professor Hoegh-Guldberg says up to 90 per cent of life has perished in previous mass extinctions and that a similar loss of life could occur in the next 100 years.

“We’re already having another mass extinction due to humans wiping out life and so on, but it looks like it could get as high as those previous events,” he said.

“So it’s the combination of this alteration to coastlines, climate change and everything, that has a lot of us worried we are going to drive the sixth extinction event and it will happen over the next 100 years because we are interfering with the things that keep species alive.

“Ocean ecosystems are in a lot of trouble and it all bears the hallmarks of human interference.

“We are changing the way the Earth’s oceans work, shifting them to entirely new states, which we have not seen before.”

He says while it is impossible to predict the future, in a century from now the world will be vastly different.

“A world without the Great Barrier Reef, where you don’t have the pleasure of going to see wild places any more,” he said.

“We might be able to struggle on with much lower population densities, but ultimately it won’t be the world we have today.

“The idea of walking in the Daintree will be a forgotten concept because these changes have occurred.”

read more at ABC News

Documentary review: ‘Into Eternity’

24 Nov

review by NoFishLeft

From the 17e till 27e of November 2010 the IDFA (International Documentary Film Festival) is held in Amsterdam. Last night I went to ‘into eternity’ a beautiful aesthetic, surreal, somewhat disturbing documentary about the legacy of nuclear waste.

In a desolated landscape in finland, the government is working on a 3 billion euro costing hiding place for nuclear waste. A place to protect our future generations from the toxic we produce. This immense tomb called ‘Onkalo’ (hiding place) will be build out of solid rock 500 meters under the ground, a place that supposedly should be save from any possible threats like earthquakes, volcanoes, wars or human economic instability. This mind-blowing project takes more than 100 years to build and will be finished in the 22th century.

Madsen the director of the film examines the possible implications and questions that rise when building a colossus tomb like this. He focus on how to build, protect and secure a structure that has to remains for at least 100.000 years. Is it even possible to build a structure that remains for more than 100.000 years? Is humanity capable to make this and how to warn future generations for this deathly tomb?

This intriguing documentary examines a very width range of questions about possible human evolutions. All breaks at the point that 100.000 years is far beyond imaging even for our brightest minds. In the end we can only assume what will happen in the future. Civilizations will fall, new ones will rise maybe on total different key pillars than our civilization now. How to warn these new possible human civilization in the far future? with language, symbols or maybe something as the painting the scream? How to warn them instead of creating curiosity of any future visitors that might seen it as a religious tomb. The engineers confess that the biggest threat will possibly lie in what they call ‘human intrusion.’

Where will the human race be in a 100, 1000 or even 10.000 years from now? The simple questions asked in this film and the honest answers by lawmakers, theologians, engineers makes this film powerful yet very disturbing. One of the serious options proposed is to try to forget this place, erase it from our human history, but than you have to be sure the structure and  roaming earth has no flaws for the coming 100.000 years

Through focusing on this immense project this documentary really shows us the bigger picture of the unsolved problem we have with nuclear waste, a growing and inevitable problem. Our nuclear reactors maybe safer than ever, but the problem of nuclear waste grows. ‘Onkalo’ at this moment is the most high tech, safest way to store the toxic waste. But it will only store 1% of the current nuclear waste there is.

With the coming prognoses of more countries embracing nuclear power again it rise some very important unanswered questions. Politicians, policy makers and lobbyists who running a successful campaign for nuclear energy keeping the waste problem out of the debate. The world looks mostly focused on the safety of it nuclear reactors instead of focusing and bringing real solution on the inevitable toxic waste that comes along with it.

Madsen didn’t made this film as an activist, he isn’t, and that’s what makes the documentary even more powerful. His background as a conceptual artist makes this documentary a stunning aesthetic film. The visual shots fits perfect with the unreal upsetting reality of the film. In a poetic style he’s telling our far future generations about this ‘Onkalo’.

This documentary is a must see for everybody who thinks about nuclear energy as a real solution for our coming energy crisis. We can not make proper decisions with out asking ourselves some serious and needed questions about the waste it brings. You can’t talk about nuclear power, without talking about the big problem that nuclear waste brings for future generations.

Production year: 2010
Runtime: 75 mins
Directors: Michael Madsen

Egypt must go green to save Red Sea

17 Oct

The Red Sea’s ecosystem is under threat from pollution and Egyptians refusing to accept there is an environmental problem

Coral reefs in the Red Sea north of Jeddah Coral reefs in the Red Sea are under threat from oil spills and plastic waste. Photograph: Hassan Ammar/AFP/Getty Images

The Red Sea is facing a crisis that could see much of its wonderful marine life cease to exist. Continued polluting of the water, constant oil spillage from offshore rigs and a lack of awareness in Egypt and around the region about the importance of maintaining vital ecosystems all contribute to the threat.

A few travellers passing through Cairo earlier this month sent me an email describing their disappointment at the diving they experienced off Egypt’s top resort, Sharm el-Sheikh. What they saw was “completely a different scene” from their first visit in 2004. “The coral was turning grey and dying,” they said.

Over and over I have heard stories from divers about the decaying state of the Red Sea’s coral reefs. It is unfortunate, but true. No longer is the Red Sea a pristine location to witness the spectacle of marine life and coral reefs. One of the main causes is the constant pouring of waste from hotels along the coastal areas, but the tourism industry more generally has done further harm by pumping chemicals and other waste products into the sea. Resolving these problems is proving extremely difficult.

Not only are coral reefs under threat, but other marine life, too. Offshore oil rigs have been in the Red Sea waters for decades, but little has been done to ensure the equipment is up to date. These rigs stream a constant pool of oil into the sea. Ahmed el-Droubi of the Hurghada Environmental Protection and Conservation Agency (Hepca) told me earlier this year that much of the dolphin population has migrated further and further south as a result.

read whole article at the Guardian.co.uk

Call to Heal the World’s Coral Reefs

14 Oct

ScienceDaily (Oct. 6, 2010) — There is still time to save the world’s ailing coral reefs, if prompt and decisive action can be taken to improve their overall health, leading marine researchers say

Writing in the journal Trends in Ecology and Evolution, eminent marine scientists from Australia and the USA have called for an international effort to improve the resilience of coral reefs, so they can withstand the impacts of climate change and other human activities.

“The world’s coral reefs are important economic, social and environmental assets, and they are in deep trouble. How much trouble, and why, are critical research questions that have obvious implications for formulating policy and improving the governance and management of these tropical maritime resources,” explains Jeremy Jackson from the Scripps Institution of Oceanography.

The key to saving the reefs lies in understanding why some reefs degenerate into a mass of weeds and never recover — an event known as a ‘phase shift’ — while on other reefs the corals manage to bounce back successfully, showing a quality known as resilience.

This underlines the importance of managing reefs in ways that promote their resilience, the researchers say.

They presented evidence that coral decline due to human activity has been going on for centuries, but has been particularly alarming in the past 50 years. In all some 125,000 square kilometres of the world’s corals have disappeared so far.

The most recent global report card (2008) estimated that 19% of all reefs were effectively lost, another 15% were critical and likely to be lost in 10-20 years, and a further 20% are under threat from local human pressures (already experiencing 20-50% loss of corals). The remaining 46% of reefs were at low risk from direct human impacts, but were nevertheless vulnerable to climate change and ocean acidification.

read whole article at Science Daily

Rob Dunbar: Discovering ancient climates in oceans and ice

13 Sep

Rob Dunbar hunts for data on our climate from 12,000 years ago, finding clues inside ancient seabeds and corals and inside ice sheets. His work is vital in setting baselines for fixing our current climate — and in tracking the rise of deadly ocean acidification.

Dive into coral reefs

10 Sep

From Nature.org

Marine Scientist Rod Salm talks about the state of our coral reefs, how and why our coral reefs are dying and how we can reverse this process.

Healthy Coral, Sick Coral: See Photos Conservancy marine scientist Rod Salm narrates a slide show about coral reefs — why they matter, what’s killing them and how we’re helping preserve them.

watch slideshow presentation here!