25/10/2017

Ocean Acidification Is Deadly Threat To Marine Life, Finds Eight-Year Study

The Guardian - Fiona Harvey

Plastic pollution, overfishing, global warming and increased acidification from burning fossil fuels means oceans are increasingly hostile to marine life
Scientists haul in samples of seawater in Svalbard, Norway. Greenpeace is working with the German marine research institute to investigate ocean acidification. Photograph: Nick Cobbing/Greenpeace
If the outlook for marine life was already looking bleak – torrents of plastic that can suffocate and starve fish, overfishing, diverse forms of human pollution that create dead zones, the effects of global warming which is bleaching coral reefs and threatening coldwater species – another threat is quietly adding to the toxic soup.
Ocean acidification is progressing rapidly around the world, new research has found, and its combination with the other threats to marine life is proving deadly. Many organisms that could withstand a certain amount of acidification are at risk of losing this adaptive ability owing to pollution from plastics, and the extra stress from global warming.
The conclusions come from an eight-year study into the effects of ocean acidification which found our increasingly acid seas – a byproduct of burning fossil fuels – are becoming more hostile to vital marine life.
“Since ocean acidification happens extremely fast compared to natural processes, only organisms with short generation times, such as micro-organisms, are able to keep up,” the authors of the study Exploring Ocean Change: Biological Impacts of Ocean Acidification found.
Marine life such as crustaceans and organisms that create calcified shelters for themselves in the oceans were thought to be most at risk, because acid seas would hinder them forming shells. However, the research shows that while these are in danger, perhaps surprisingly, some – such as barnacles – are often unaffected, while the damage from acidification is also felt much higher up the food chain, into big food fish species.
An unhealthy pteropod shows the effects of ocean acidification, including dissolving shell ridges on its upper surface, a cloudy shell, and severe abrasions. Photograph: Courtesy of NOAA
Ocean acidification can reduce the survival prospects of some species early in their lives, with knock-on effects. For instance, the scientists found that by the end of the century, the size of Atlantic cod in the Baltic and Barents Sea might be reduced to only a quarter of the size they are today, because of acidification.
Peter Thomson, UN ambassador for the oceans and a diplomat from Fiji, which is hosting this year’s UN climate change conference in Bonn, urged people to think of the oceans in the same terms as they do the climate. “We are all aware of climate change, but we need to talk more about ocean change, and the effects of acidification, warming, plastic pollution, dead zones and so on,” he said. “The world must know that we have a plan to save the ocean. What is required over the next three years is concerted action.”
The eight-year study was carried out by the Biological Impacts of Ocean Acidification group (known as Bioacid), a German network of researchers, with the support of the German government, and involved more than 250 scientists investigating how marine life is responding to acidification, and examining research from around the world. The study was initiated well before governmentssigned a global agreement on climate change at Paris in 2015, and highlights how the Paris agreement to hold warming to no more than 2C may not be enough to prevent further acidification of the world’s seas.
Governments will meet in Bonn in November to discuss the next steps on the road to fulfilling the requirements of the Paris agreement, and the researchers are hoping to persuade attendees to take action on ocean acidification as well.
A scientist feeds coral in a lab to study the impact of multiple climate stressors on coral reef. Photograph: Joe Raedle/Getty Images 
Ocean acidification is another effect of pouring carbon dioxide into the atmosphere, as the gas dissolves in seawater to produce weak carbonic acid. Since the industrial revolution, the average pH of the ocean has been found to have fallen from 8.2 to 8.1, which may seem small but corresponds to an increase in acidity of about 26%. Measures to reduce the amount of carbon dioxide reaching the atmosphere can help to slow down this process, but only measures that actively remove carbon already in the atmosphere will halt it, because of the huge stock of carbon already in the air from the burning of fossil fuels.
Worse still, the effects of acidification can intensify the effects of global warming, in a dangerous feedback loop. The researchers pointed to a form of planktonic alga known as Emiliania huxleyi, which in laboratory experiments was able to adapt to some extent to counter the negative effects acidification had upon it. But in a field experiment, the results were quite different as the extra stresses present at sea meant it was not able to form the extensive blooms it naturally develops. As these blooms help to transport carbon dioxide from the surface to the deep ocean, and produce the gas dimethyl sulfide that can help suppress global warming, a downturn in this species “will therefore severely feed back on the climate system”.

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Once Were Sceptics: What Convinced These Scientists That Climate Change Is Real?

ABC Science - Nick Kilvert

As climate change has become politicised, many find it difficult to change their position. (Getty: Paul Souders)
Up until a few years ago, Richard Muller was often quoted by sceptics as a credible, high-profile scientist who doubted the consensus on climate change.
Today, he starts his lectures by stating a few things he believes to be facts.
"Al Gore has grossly exaggerated global warming. And if you watch his movie you have more misinformation than information.
"However, global warming is real. It is caused by humans. It is caused by the human emission of greenhouse gases, and I personally feel we have to stop it somehow."
In 2010, Professor Muller from Berkeley University was funded to carry out a comprehensive study by a group of individuals who doubted the Intergovernmental Panel on Climate Change (IPCC) data.
They believed that urban heat islands, data-selection bias, and inaccurate climate models were being glossed over by scientists.

'Don't trust us' approach key to convincing sceptics
Professor Muller says people need to remain sceptical about how we tackle climate change. (Getty: Dan Tuffs)
Professor Muller and his team — all of whom doubted climate change was happening or that carbon dioxide was its cause — were shocked to find a correlation between carbon dioxide emissions and warming.
"That was the biggest surprise of all," he said.
"Volcanoes, sunspots, orbital changes, we could all rule out. What we could do is show [that warming] matched the carbon dioxide exceedingly well."
To address what he sees as a lack of transparency in some IPCC reporting, his team made all their data available online.
"The teams that did [the previous studies] said 'trust us'. We said 'don't trust us, here's what we did'. And for that reason I think we were able to win over the sceptics," he said.
However, he said there was still room for scepticism.
"Yes I am a converted sceptic. However, anybody today who is not a sceptic about the solutions being proposed is not thinking them through."

Dr Anthony Purcell, Research Fellow, ANU
Dr Purcell says his views of climate change have affected some personal relationships. (Supplied: ANU)
"I doubted that the climate could be so dramatically sensitive to small perturbations, especially on a short timescale," Anthony Purcell said of his initial position on climate change.
Dr Purcell, a mathematician and geophysicist, said his view was largely shared by the members of his social circle.
"Pretty much everybody in my personal life was either agnostic or deeply hostile to the concept of anthropogenic climate change," he said.
"[My father is] a deeply entrenched climate denialist."
In 2010, he read an article in The Australian newspaper in which the distinguished scientist Professor Frank Fenner predicted that "Homo sapiens will become extinct, perhaps within 100 years" due to climate change.
Dr Purcell said that statement shook him.
"This was a responsible scientist making a public declaration and it seemed to me to raise alarm bells," he said.
"I hadn't been aware that this was even something that might be considered as a possible outcome."
Personal relationships 'severely eroded' by change of view
Core samples taken from a diamond drill show sediment as it was laid down. (Getty: Mo Morad.)
A deep-sea core sample, containing layers of sediment laid down over millions of years, demonstrated first-hand that Professor Fenner's prediction had a historic precedent.
One of the layers in the core sample was around 55-million-years old, from what is known as the Palaeo-Eocene thermal maximum (PETM).
"All of a sudden that [carbon-rich material in the sediment] vanishes and it's just this dingy mud with no evidence of biological activity at all," he said.
"That was a response to a four-degree temperature increase that occurred over 20,000 years. We're looking at something that's a hundred-times faster than that."
Dr Purcell said his acceptance of the climate science had a significant personal toll.
"It's deeply impacted my relationship with my father," he said.
"It's severely eroded our relationship and our ability to communicate."

Professor David Karoly, University of Melbourne, Atmospheric Science
Professor Karoly initially set out to disprove climate change. (Supplied: David Karoly)
David Karoly is one of the world's pre-eminent climate scientists, and advises the Australian Government through the Climate Change Authority (CCA).
But back in 1986, he believed he had a way to prove climate change had nothing to do with carbon emissions.
"I was aware from theoretical considerations that we would expect a specific pattern of temperature changes associated with increasing greenhouse gases," he said.
"Which is warming in the lower atmosphere and cooling in the stratosphere at heights above 15 kilometres.
"And I thought I would use that signature to show that in fact what was actually occurring in the data was due to natural variability like El Nino or increasing sunlight, and not due to human-caused climate change."

Climate Change Authority's Professor David Karoly speaks with ABC News Breakfast

Professor Karoly submitted an abstract of his forthcoming research to a climate-change conference in Melbourne in 1986. He expected his findings to show that there was no carbon-driven-warming signature.
"The more I looked, the more I found this signature of warming in the lower atmosphere and cooling in the upper atmosphere," he said.
By the time he came to present his paper, he had to switch his position in support of anthropogenic climate change.
But that was the '80s and climate science had yet to be deeply politicised.
He says changing his view on climate change was not a big deal at the time.
"I was coming into it as what I believe all scientists are — sceptical and wanting to test a hypothesis — and that's what I did."

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New Zealand Government To Plant 100 Million Trees Yearly

EcoWatch - Lorraine Chow

Paradise, New Zealand
New Zealand's next prime minister Jacinda Ardern has set ambitious environmental policies to confront a warming planet.
 "I do anticipate that we will be a government, as I said during the campaign, that will be absolutely focused on the challenge of climate change," said Ardern, whose Labour party has signed a coalition agreement with the New Zealand First party.
"That will include a zero carbon act. That will include an independent climate commission. That will include making sure that we have an all gases, all sectors emissions trading scheme," she added.

Jacinda Ardern discusses climate change

 Other green initiatives include transitioning the country's power grid to 100 percent renewable energy, a significant investment in regional rail, and a goal to plant 100 million trees a year through the "Billion Trees Planting Programme."
According to the Associated Press, Arden said the goal of doubling the amount of trees the country plants each year is "absolutely achievable" by using land that was marginal for farming animals.
The Green Party will support the incoming government with a confidence and supply agreement, which includes a major goal of net zero carbon emissions by 2050.
"All three parties share an absolute commitment to addressing climate change," Ardern said.
As Climate Change News noted, New Zealand's 2050 net zero target puts it in the same hat as Sweden, which wants net zero by 2045, and Norway, which is aiming for 2030. Other developed nations such as the U.S, Canada, Mexico, the U.K., France and Germany have committed to cutting emissions but none to net zero.
More than 80 percent of New Zealand's electricity already comes from renewables, primarily through hydropower, geothermal and wind. The AP reported that Ardern wants to ramp it to 100 percent by 2035 in part by investing more in solar, which currently takes up only 0.1 percent of the country's total renewable energy slice.
The 37-year-old—New Zealand's youngest leader in more than 150 years—plans to take the country on a more liberal path after nine years of conservative rule. Other initiatives include increasing the minimum wage, free doctors' visits for all under 14-years-old, and a review and reform of the Reserve Bank Act.

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