Lethal Heating: 12/02/17

02/12/2017

El Niño Might Speed Up Climate Change

Scientific American - Tim Vernimmen

Scientists have evidence that El Niño boosts CO2 levels, and they are pinning down how

This picture taken on July 26, 2017 shows an Indonesian ranger inspecting the peat forest fire at Meulaboh, Aceh province. Credit: Chandeer Mayhuddin Getty Images

Every two to seven years, abnormally warm water in the Pacific Ocean causes an atmospheric disturbance called El Niño. It often makes extreme weather worse in various places around the world: greater floods, tougher droughts, more wildfires. Now scientists have new evidence indicating El Niño conditions might also add extra carbon dioxide to the atmosphere as well as lessen the ability of trees to absorb the greenhouse gas.
By certain measures, the most recent El Niño, which held sway in 2015 and 2016, was one of the three strongest on record, along with episodes in 1982–1983 and 1997–1998. Although its impacts on land were not clearly stronger than those of the other events, it appears it was the major culprit for a record increase in CO₂ during its reign. “CO₂ emissions from fossil fuels and industry did not really change from 2014 to 2016,” says climate scientist Pierre Friedlingstein at the University of Exeter in England, and an author of the 2017 carbon budget report released by the Global Carbon Project in November. So the dramatic increase, he says, must be due to how land and sea responded to El Niño.
A recent article in Science about satellite measurements made during El Niño by NASA’s Orbiting Carbon Observatory-2 showed most of the extra CO₂ originated in the tropics. It also suggested each tropical region contributed a similar amount of CO₂ as in other strong El Niño years, each in its own way. In South America's Amazon, for example, slower-growing plants absorbed less CO₂, whereas in Africa, plants and soils released more of the gas.
The observations are based on satellite readings of CO₂, carbon monoxide (which is released by wildfires) and other factors like the fluorescence of the chlorophyll in plant tissues (which reflects growth). But scientists would want some ground-truthing to prove El Niño conditions in the tropics boosted atmospheric CO₂ levels. In the past, field data from plants and soils during an El Niño has been thin, but in 2015 researchers were better prepared.
Ecosystem scientist Yadvinder Malhi, at the University of Oxford, and colleagues analyzed data from 54 tropical forest plots in Ghana, Gabon, Malaysia, Brazil and Peru, which they presented at a recent meeting Mahli organized in London. The ground data confirmed what the satellite data had suggested: the tropics are key. The amount of CO₂ released from the sites predicted the atmospheric levels “surprisingly well,” according to Malhi. “In contrast to long-term climate change,” he said at the meeting, “everybody agrees that El Niño makes the amount of CO₂ in the atmosphere go up faster than usual.”
The next question was how much each continent contributed. Malhi says the Amazon appears to be the biggest player. “Africa always emits a lot of CO₂, since it has a lot of wildfires, especially in the savannas. But its tropical forests and savannas didn’t behave very differently from other years,” he says. In the Amazon, however, “the emissions seemed largely due to respiration: CO₂ released from plants, decaying logs and the soil.”
Further analysis will allow Malhi’s team to distinguish between those different sources, which is important for predicting longer-term impacts. If, for example, it turns out the extra CO₂ released during El Niño is largely due to microbial activity in soils and decomposing plant material, Malhi says, “I wouldn’t expect it to last” as the world warms further. If the increase is coming from the plants because they are respiring more, that might be a signal of long-term stress that may continue to raise CO₂ levels.
As a carbon booster, El Niño could hasten rising temperatures, bringing the world to dangerous thresholds sooner than thought. It could also enhance feedbacks between climate and vegetation that could reduce plants’ ability to absorb CO₂ in non-Niño years as well. If bad droughts or wildfires kill many trees, for example, forests and their carbon sequestering potential may take centuries to recover, if ever.
Wildfires are a big concern. They were not quite as pervasive in 2015–2016 as they were in 1997–1998, when they were the most important global source of extra CO₂. In 2015–2016, “a bit of rain at just the right moment prevented the Southeast Asian peat forest fires from spreading as widely as they did two decades ago,” says climate scientist Guido van der Werf at Vrije University Amsterdam. “Nevertheless, fire is a growing problem in the region.” Drought and heat make the forests more vulnerable. Wildfires release a lot of CO₂, and they also eliminate the trees that might store more CO₂ in the future.
Even in the absence of fire, El Niño might be killing trees. In northern Australia's remote Gulf of Carpentaria, more than 18,200 acres of mangrove vegetation died during the last El Niño due to a convergence of severe drought and unprecedented high temperatures. Death by drought may threaten trees in the Amazon as well.
To transport water from roots up to leaves, trees depend on tension created by the difference in water availability in the soil and the atmosphere, says plant physiologist Lucy Rowland at Exeter. “If it is very dry, however, that tension can get too high,” she says. “If that happens, the column of water in the trees’ transport vessels breaks. Then air gets in, blocking water flow like a bubble in your central heating system does.”
The only way trees can fix this problem is by growing new vessels—if the lack of water does not kill them first. Rowland is also investigating whether severe drought hampers the ability of tropical vegetation to absorb more CO₂ as the atmospheric concentration rises. Right now, she says, the way climate models incorporate vegetation’s response to drought is too simplistic.
For now tropical trees appear to have returned to normal, their ecosystems absorbing more CO₂ than they emit, Friedlingstein concludes. Unfortunately, man-made emissions have returned to their old status as well. “After two years of stability,” he adds, “they are going up again.”

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Scientists Look To Bali Volcano For Clues To Curb Climate Change

Reuters - Alister Doyle

Volcanoes are emerging as natural laboratories to mimic "geo-engineering" - a possible short-cut to curb global warming by injecting sun-dimming chemicals high above the Earth

Lava inside the crater of Mount Agung volcano reflects off ash and clouds, while it erupts, as seen from Amed, Karangasem Regency, Bali, Indonesia, Nov. 30, 2017. REUTERS/Darren Whiteside

Summary

Volcanoes become geo-engineering laboratories
Repeat of 1963 Bali eruption could cool planet

OSLO - Climate scientists are tracking an erupting volcano on the Indonesian holiday island of Bali for clues about a possible short-cut to curb global warming by injecting sun-dimming chemicals high above the Earth.
Volcanoes are emerging as natural laboratories to mimic "geo-engineering", the idea that governments could deliberately add a veil of sulphur dioxide high above the planet as an artificial sunshade to curb man-made global warming.
Ash and smoke ejected so far by the Agung volcano, which has been erupting in recent days, has not been big enough or high enough in the atmosphere to cool world temperatures. But scientists say they are studying what would happen if the volcano has a repeat of a far bigger eruption in 1963.
"I've been doing some Bali simulations with the U.K. Met office climate model as 'what ifs', and also some geo-engineering simulations," said Jim Haywood, professor of atmospheric science at the University of Exeter.
He estimated that Agung spewed eight million tonnes of sulphur dioxide into the stratosphere in 1963, about 10-15 kms above the Earth's surface, enough to trim world temperatures for months. That eruption killed more than 1,000 people in Bali.
"Many scientists are keeping an eye on the Agung eruption in Bali," said Alan Robock, a professor of climate science at Rutgers University. "Volcanic eruptions serve as an analogue for the idea of humans creating such a cloud."
Satellite measurements of eruptions have only recently become precise enough to exploit volcanoes as models for geo-engineering.
That was impossible, for instance, when Mount Pinatubo in the Philippines erupted in 1991 and blew about 20 million tonnes of sulphur dioxide into the stratosphere, the second biggest eruption of the 20th century after one in Alaska in 1912.
Mount Pinatubo had a cooling effect on the Earth because the sun-dimming sulphur spread worldwide.
"Since Pinatubo we've got a lot better" at measuring the effects of big eruptions, said Matthew Watson of the University of Bristol. "We're waiting for something to happen on a scale where we can start thinking about what it means for geo-engineering."
He estimated that the Agung volcano has probably ejected only about 10,000 tonnes of sulphur dioxide in the latest eruption, and not as high as the stratosphere.
Governments agree they should focus most on cutting greenhouse gas emissions under the 2015 Paris agreement rather than on science-fiction-like short-cuts to limit temperatures blamed for causing more heatwaves, floods and rising sea levels.
But current policies put the world on track to overshoot the Paris goal of limiting rising temperatures to "well below" two degrees Celsius (3.6 Fahrenheit) above pre-industrial times.
U.S. President Donald Trump, who doubts man-made emissions are the prime cause of warming, also plans to pull out of the Paris deal and promote the U.S. fossil fuel industry. That risks further weakening the Paris plan.

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German Court To Hear Peruvian Farmer's Climate Case Against RWE

The Guardian - Agence France-Presse

Decision to hear Saul Luciano Lliuya’s case against the energy giant is a ‘historic breakthrough with global relevance’, campaigners say

Saul Luciano Lliuya, a farmer from Peru, at the UN climate talks in Bonn earlier this month. Photograph: Anthony Kwan/Getty Images

A German court has ruled that it will hear a Peruvian farmer’s case against energy giant RWE over climate change damage in the Andes, a decision labelled by campaigners as a “historic breakthrough”.
Farmer Saul Luciano Lliuya’s case against RWE was “well-founded,” the court in the north-western city of Hamm said on Thursday.
Lliuya argues that RWE, as one of the world’s top emitters of climate-altering carbon dioxide, must share in the cost of protecting his hometown Huaraz from a swollen glacier lake at risk of overflowing from melting snow and ice.
RWE’s power plants emitted carbon dioxide that contributed to global warming, increasing local temperatures in the Andes and putting property at risk from flooding or landslides, Lliuya argues.
“Even people who act according to the law must be held responsible for damage they cause to property,” the judges said.
Now the court must decide whether “the accused’s contribution to the chain of events depicted here is measurable and calculable,” they added.
“This is a major success not just for me, but for the people of Huaraz and everywhere in the world threatened by climate risks,” Lliuya said in a statement circulated by NGO Germanwatch.
He wants RWE to pay €17,000 ($20,000) towards flood defences for his community in Peru’s northern Ancash region.
The 37-year-old also wants the German company to reimburse him for the €6,384 he himself has spent on protective measures.
Lliuya bases his claims on a 2013 climate study which found that RWE was responsible for around 0.5% of global emissions “since the beginning of industrialisation”.
The court said in a statement that it will choose experts to evaluate the claim in cooperation with both plaintiff and defendant, with Lliuya paying about €20,000 in fees up front.
“It will be up to the experts to quantify [RWE’s] role, which could be different” from the amount he claims, the judges said.
After an initial hearing in mid-November, the court in the north-western city of Hamm gave both sides until Thursday to provide further arguments to help them decide whether the case should go ahead.
The decision to hear the case is a “historic breakthrough with global relevance,” Germanwatch, which has backed Lliuya’s claim, said in a statement.
“Major emitters of greenhouse gases can be held responsible for protective measures against climate damage.”
RWE could not immediately be reached for comment.
But the firm has insisted that the complaint was “not admissible” and was even “unjustified”, arguing that a single company cannot be held liable for specific consequences of climate change.
A lower court in the German city of Essen, where RWE is based, initially found that the lawsuit against the energy giant was unfounded.
The company has in the past said it did not understand why it has been singled out for legal action, stressing the efforts it had made to become more environmentally friendly.

In this Aug. 12, 2016 photo, a group of tourists walk past a photo featuring an image of the Pastoruri glacier before its retreat, during a tour called “The Route of Climate Change” in Huaraz, Peru. Benjamin Morales Arnao, the head of Peru’s National Institute for Glacier Research, said that while the country’s glaciers “are a source of life, due to their water resources and biodiversity ... these glaciers are also a source of glacier glacial catastrophes.” (AP Photo/Martin Mejia) Photograph: Martin Mejia/AP

As well as modernising its coal-fired power plants to reduce CO2 emissions, RWE has invested billions in renewable energy as part of Germany’s move away from fossil fuels, it says.
Shares in RWE fell on the news, losing 0.31% in Frankfurt against a DAX index of blue-chip German shares up 0.52%.
The Peruvian’s case comes at a time when German politics is sharply divided over how to balance climate action against economic growth.
A government-directed “energy transition” to renewables, rather than nuclear power and fossil fuels, is making only halting progress, while environmentalists are pushing the country’s powerful auto industry to produce less polluting vehicles after a series of scandals.
Climate and energy policy was among the most bitterly disputed issues in three-way coalition talks between chancellor Angela Merkel’s conservatives, the pro-business Free Democrats and the ecologist Greens before they broke down this month.

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