10/11/2016

Global 'Greening' Has Slowed Rise Of CO2 In The Atmosphere, Study Finds

The Guardian - 

Increased growth of plants fertilised by higher CO2 levels is only partly offsetting emissions and will not halt dangerous warming, scientists conclude
Natural vegetation absorbs about a quarter of the carbon emissions created by burning fossil fuels. Photograph: Kuni Takahashi/Getty Images
A global “greening” of the planet has significantly slowed the rise of carbon dioxide in the atmosphere since the start of the century, according to new research.
More plants have been growing due to higher CO2 levels in the air and warming temperatures that cut the CO2 emitted by plants via respiration. The effects led the proportion of annual carbon emissions remaining in the air to fall from about 50% to 40% in the last decade.
However, this greening is only offsetting a small amount of the billions of tonnes of CO2 emitted from fossil fuel burning and other human activities and will not halt dangerous global warming. “Unfortunately, this increase is nowhere near enough to stop climate change,” said Dr Trevor Keenan, at the Lawrence Berkeley National Laboratory in the US, who led the new work.
The absolute level of CO2 in the atmosphere is continuing to rise, breaking the milestone of 400 parts per million (ppm) in 2015, and rising temperatures continue to surpass records.
The World Meteorological Organisation (WMO) warned on Tuesday that 2011-15 was the hottest five-year period ever recorded and that climate change had increased the risk of half of extreme weather events, with some heatwaves made 10 times more likely by global warming.
The new study on global greening is published in Nature Communications by an international team of scientists who concluded cutting carbon emissions remains vital to preventing severe climate change.
“Enhanced carbon uptake by the biosphere to date has slowed the growth rate of atmospheric CO2 and our results [suggest] uptake has been especially strong recently,” they wrote. “Without effective reduction of global CO2 emissions, however, future climate change remains a stark reality.”
Prof Corinne Le Quéré, director of the Tyndall Centre at the University of East Anglia, who was not part of the new research, said: “Natural vegetation is a fantastic help in slowing down climate change by absorbing about a quarter of our carbon emissions from burning fossil fuels.
“Fundamentally though, this help is not enough to stop the planet warming – far from it – carbon emissions have to drop to almost zero to stop global warming.”
The scientists used extensive land, air and satellite data to assess how carbon uptake by plants has changed over recent decades and used modelling to help untangle the different factors underlying the changes. It has been unclear whether the fertilisation effect of higher CO2 levels for plants is outweighed by the harm caused to them by warming and droughts.
The researchers found that between 1960 and 2000 the rise of CO2 in the atmosphere was increasing every year, but that after 2000 the rate slowed to about the same increase every year. They found that the main factor was the higher CO2 levels, which were just 290ppm at the start of the last century, compared to 400ppm today.
Another factor was the slower rate of global temperature increase after 2000, the so-called “pause” during which more of the heat trapped by greenhouse gases went into the oceans than the air. This meant the increasing respiration of plants driven by rising heat was curbed, trapping more carbon.
Prof Chris Rapley, at University College London, said: “The researchers make it clear that this effect is almost certainly temporary. The ‘greening’ effect of CO2 will ultimately be overwhelmed by the plants’ own respiration and decay, which will cause even more CO2 to be released.”
The research also shows the importance of preserving forests and other ecosystems that absorb carbon, said Prof Dave Reay, at the University of Edinburgh: “The land and oceans have been bailing us out of dangerous climate change for decades. Unless key carbon sinks such as forests are better protected, the delicate green veil that has saved our worst climate blushes will be in tatters.”
The WMO submitted its new report to the UN climate change summit taking place in Morocco. “We just had the hottest five-year period on record, with 2015 claiming the title of hottest individual year. Even that record is likely to be beaten in 2016,” said WMO secretary-general, Petteri Taalas.
“The effects of climate change have been consistently visible on the global scale since the 1980s: rising global temperature, both over land and in the ocean; sea-level rise; and the widespread melting of ice,” he said. “It has increased the risks of extreme events such as heatwaves, drought, record rainfall and damaging floods.”

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Radical Overhaul Needed To Halt Earth’s Sixth Great Extinction Event

The Conversation -  | 

The great grey owl is imperiled by intensive logging of northern-hemisphere forests. Copyright Ondrej Prosicky/Shutterstock.
Life has existed on Earth for roughly 3.7 billion years. During that time we know of five mass extinction events — dramatic episodes when many, if not most, life forms vanished in a geological heartbeat. The most recent of these was the global calamity that claimed the dinosaurs and myriad other species around 66 million years ago.
Growing numbers of scientists have asserted that our planet might soon see a sixth massive extinction — one driven by the escalating impacts of humanity. Others, such as the Swedish economist Bjørn Lomborg, have characterised such claims as ill-informed fearmongering.
We argue emphatically that the jury is in and the debate is over: Earth’s sixth great extinction has arrived.

Collapse of biodiversity
Mass extinctions involve a catastrophic loss of biodiversity, but what many people fail to appreciate is just what “biodiversity” means. A shorthand way of talking about biodiversity is simply to count species. For instance, if a species goes extinct without being replaced, then we are losing biodiversity.
But there’s much more to biodiversity than just species. Within each species there usually are substantial amounts of genetic, demographic, behavioural and geographic variation. Much of this variation involves adaptations to local environmental conditions, increasing the biological fitness of the individual organism and its population.
Natural variation within two species of sea snails. Upper row: Littorina sitkana. Lower row: Littorina obtusata. Copyright David Reid/Ray Society.
And there’s also an enormous amount of biodiversity that involves interactions among different species and their physical environment.
Many plants rely on animals for pollination and seed dispersal. Competing species adapt to one another, as do predators and their prey. Pathogens and their hosts also interact and evolve together, sometimes with remarkable speed, whereas our internal digestive systems host trillions of helpful, benign or malicious microbes.
Hence, ecosystems themselves are a mélange of different species that are continually competing, combating, cooperating, hiding, fooling, cheating, robbing and consuming one another in a mind-boggling variety of ways.
All of this, then, is biodiversity - from genes to ecosystems and everything in between.

The modern extinction spasm
No matter how you measure it, a mass extinction has arrived. A 2015 study that one of us (Ehrlich) coauthored used conservative assumptions to estimate the natural, or background rate of species extinctions for various groups of vertebrates. The study then compared these background rates to the pace of species losses since the beginning of the 20th century.
Cumulative vertebrate species extinctions since 1500 compared to the ‘background’ rate of species losses. G. Ceballos et al. (2015) Scientific Advances.
Even assuming conservatively high background rates, species have been disappearing far faster than before. Since 1900, reptiles are vanishing 24 times faster, birds 34 times faster, mammals and fishes about 55 times faster, and amphibians 100 times faster than they have in the past.
For all vertebrate groups together, the average rate of species loss is 53 times higher than the background rate.

Extinction filters
To make matters worse, these modern extinctions ignore the many human-caused species losses before 1900. It has been estimated, for instance, that Polynesians wiped out around 1,800 species of endemic island birds as they colonised the Pacific over the past two millennia.
And long before then, early human hunter-gatherers drove a blitzkrieg of species extinctions — especially of megafauna such as mastodons, moas, elephant birds and giant ground sloths — as they migrated from Africa to the other continents.
In Australia, for instance, the arrival of humans at least 50,000 years ago was soon followed by the disappearance of massive goannas and pythons, predatory kangaroos, the marsupial “lion”, and the hippo-sized Diprotodon among others.
Changes in climate could have contributed, but humans with their hunting and fires were almost certainly the death knell for many of these species.
As a result of these pre-1900 extinctions, most ecosystems worldwide went through an “extinction filter”: the most vulnerable species vanished, leaving relatively more resilient or less conspicuous species behind.
Giant ground sloths such as this elephant-sized Megatherium vanished soon after humans arrived in the New World. Copyright Catmando.
And it’s the loss of these survivors that we are seeing now. The tally of all species driven to extinction by humans from prehistory to today would be far greater than many people realise.

Vanishing populations
The sixth great extinction is playing out in other ways too, especially in the widespread annihilation of millions (perhaps billions) of animal and plant populations. Just as species can go extinct, so can their individual populations, reducing both the genetic diversity and long-term survival prospects of the species.
For example, the Asian two-horned rhinoceros once ranged widely across Southeast Asia and Indochina. Today it survives only in tiny pockets comprising perhaps 3% of its original geographic range.
Three-quarters of the world’s largest carnivores, including big cats, bears, otters and wolves, are declining in number. Half of these species have lost at least 50% of their former range.
Likewise, except in certain wilderness areas, populations of large, long-lived trees are falling dramatically in abundance.
WWF’s 2016 Living Planet Report summarises long-term trends in over 14,000 populations of more than 3,700 vertebrate species. Its conclusion: in just the last four decades, the population sizes of monitored mammals, birds, fish, amphibians and reptiles have shrunk by an average of 58% worldwide.
And as populations of many species collapse, their crucial ecological functions decline with them, potentially creating ripple effects that can alter entire ecosystems.
Hence, disappearing species can cease to play an ecological role long before they actually go extinct.
Once a widespread and dominating predator, the tiger today is vanishingly rare across most of its former range. Copyright Matt Gibson
Paying the extinction debt
Everything we know about conservation biology tells us that species whose populations are in freefall are increasingly vulnerable to extinction.
Extinctions rarely happen instantly, but the conspiracy of declining numbers, population fragmentation, inbreeding and reduced genetic variation can lead to a fatal “extinction vortex”. In this sense, our planet is currently accumulating a large extinction debt that must eventually be paid.
And we’re not just talking about losing cute animals; human civilisation relies on biodiversity for its very existence. The plants, animals and microorganisms with which we share the Earth supply us with vital ecosystem services. These include regulating the climate, supplying clean water, limiting floods, running nutrient cycles essential to agriculture and forestry, controlling serious crop pests and carriers of diseases, and providing beauty, spiritual and recreational benefits.
Are we preaching doom? Far from it. What we’re saying, however, is that life on Earth is ultimately a zero-sum game. Humans cannot keep growing in number and consuming ever more land, water and natural resources and expect all to be well.
Limiting harmful climate change has become a catchphrase for battling such maladies. But solutions to the modern extinction crisis must go well beyond this.
We also have to move urgently to slow human population growth, reduce overconsumption and overhunting, save remaining wilderness areas, expand and better protect our nature reserves, invest in conserving critically endangered species, and vote for leaders who make these issues a priority.
Without decisive action, we are likely to hack off vital limbs of the tree of life that could take millions of years to recover.
The Slow Loris, a primitive primate, is a denizen of intact rainforests in southern Asia. Copyright hkhtt hj
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‘Critical Moment’ as UN Climate Talks Resume

Climate Central - 

Leaders of nations overwhelmed by fallouts from wars and ravaged by political divisions are gathering in western Morocco, where they will attempt during the next two weeks to unite around a cooperative new approach to easing the worsening ravages of global warming.
Ahead of the first major United Nations climate negotiations since an aspirational agreement was struck in Paris last December, the world’s greatest greenhouse gas polluters, China and the U.S., have signaled that they will continue to try to lead the world toward ambitious climate action following decades of inaction.
The meetings in Marrakesh began Monday amid uncertainty over the direction of the U.S. after its election on Tuesday. The presidential candidates hold polar views on the importance of slowing climate change. Like President Obama, Democrat Hillary Clinton is supportive of the Paris climate agreement; Republican Donald Trump is derisive.
Senior U.N. climate officials at the opening ceremony of a new round of United Nations climate talks. Credit: UNFCCC/flickr
“The Paris Agreement was a turning point in terms of setting in place a framework, an international framework for action,” John Morton, director for energy and climate change at the National Security Council, a White House body, told reporters last week. “We intend to really intensify our work in turning toward implementation.”
Even as Tuesday’s election rattles climate negotiators, China and the U.S. have been doubling down on their growing commitments to fighting climate change. China has announced a new goal for easing its dependence on fossil fuels by 2020. During the Marrakesh meetings, the U.S. will publish ideas for eliminating most of the carbon pollution from its economy by 2050.
“We’re at an unprecedented stage in climate negotiations,” Morton said. “2016 has been a truly historic year for international climate action.”
Following a week of networking and low-level talks, senior government officials will begin four days of high-level negotiations on Nov. 15. They will haggle over rules about the information governments should share about progress toward reducing climate impacts. The Paris agreement features non-binding national climate pledges, and rules will be considered for improving those pledges over time. Timelines and bookkeeping rules will be drafted.
Poor and developing countries will pressure those nations that got rich by burning fossil fuels to make good on their promises of helping them meet costs of deploying solar and wind energy and adapting to climate change’s impacts.
Since 2009, Western governments have been pledging the “mobilizing” of $100 billion a year in climate financing by 2020 for poorer nations, though the Paris agreement failed to lay out rules for ensuring those promises are kept.
“The money that was promised is only being delivered in a trickle,” said Saleem Huq, a climate change fellow at the International Institute for Environment and Development, a group based in London that promotes sustainable development. “We need to open the spigots in Marrakesh.”
The meetings are being held near the end of what will be the third consecutive year of record-breaking heat worldwide. Rising temperatures from greenhouse gases are powering typhoons and hurricanes, and stoking wildfires across the American West.
Amid the heat, corals are bleaching and dying through the tropics. Rising seas are killing forests and flooding roads and neighborhoods along the East and Gulf coasts. Heat waves are killing more people and reshaping ecosystems.
These riverside trees in coastal New Jersey were killed by the effects of rising seas. Credit: Ted Blanco/Climate Central
The Paris agreement was swiftly ratified by governments as temperatures continued to rise this year, and as prices for clean energy continued to fall. The agreement legally took effect on Friday, surprising climate negotiators and campaigners accustomed to slower progress on climate diplomacy. It formally covers greenhouse gas pollution released during the 2020s.
“The success of the Paris agreement depends on its effective implementation, and that’s where the focus is turning now,” said Elliot Diringer of the American nonprofit Center for Climate and Energy Solutions. “We’re entering a new phase that isn’t quite as exciting, but is just as critical.”
The Paris agreement involves nearly 200 countries, but it was largely fostered through climate agreements struck between the U.S and China in 2014 and 2015. Those countries are the world’s greatest climate polluters, but they had previously been reluctant to tackle warming. That left Europe and vulnerable countries toiling for years as lonely champions of an insipid quest to protect the climate.
“We’re at a critical moment, in the sense that we finally have all countries on board committing to do their best,” Diringer said. “Now we need to make sure we put in place the rules to hold them to that.”
After a 1997 U.N. climate agreement failed to slow warming, and after a round of climate talks collapsed in 2009, American diplomats began urging their counterparts abroad to abandon long-running efforts to force countries to reduce greenhouse gas pollution. Instead, governments are now unifying around an untested voluntary approach to reducing pollution, with non-binding pledges underpinning the pact agreed upon in Paris.
The Marrakesh talks will test that global unity at a time when unity in much of the world seems fragile and elusive.
“U.S. standing in the world will be bruised by the U.S. election, no matter who wins; Britain’s ability to lead will be undermined by Brexit,” said University of California, San Diego international relations professor David Victor.
“To some degree, the world is always being rocked by events,” Victor said. “That’s one reason why climate change is such a hard topic to address. It’s the quintessential long-term problem, and most of politics is about managing quintessential short-term problems and crises.”
Determining success in Marrakesh will be difficult, with grunt work on rulemaking largely replacing the diplomatic showmanship that dominated the Paris talks last year.
“I don't see any major successes likely,” Victor said, warning of problems if divisions on financial issues or other vexing topics prevent decisions from being made. “That would be a big setback and would blood the waters with talk of the Paris agenda failing.”
Westerners angered by migration and trade are embracing nativist leaders and causes, just as years of climate diplomacy culminates in the makings of a cooperative strategy for tackling warming. The divisiveness defining America’s presidential election is echoing a brawl in the UK over a withdrawal from the European Union.
Wars are tearing up the Middle East, fueling a global refugee crisis. Turkey has been imprisoning teachers and journalists. The leader of the Philippines may break long-standing militaries ties with the U.S.
Climate change has played a substantial role in worsening wildfire seasons in the American West. Credit: Russ Allison Loar/flickr
Officials from China, France and Brazil have lashed out at Trump over his opposition to the Paris agreement. Amid condemnation of its atrocities in Syria and its invasion of Ukrainian territory, Russia, which promised nothing meaningful under its Paris climate pledge, has been accused of using espionage to help get Trump elected.
Against this backdrop, the climate talks could be an “oasis of civility,” said Harvard economics professor Robert Stavins, who heads the Harvard Project on Climate Agreements — “a temporary hiatus from the troubling issues that government officials and civil society are now confronting on a seemingly daily basis.”
If Trump is elected, or if the outcome of the presidential election remains in doubt, however, Stavins warned the talks would probably be held in a “depressed” state.
The Paris agreement aims to keep warming to “well below” 2°C (3.6F). The planet has already warmed nearly half that much since pre-Industrial times. In February and March it got so hot that the Paris agreement’s headier goal of preventing 1.5°C of warming was briefly blown, before global temperatures eased slightly, even as monthly temperature records continued to tumble through the summer and fall.
Carbon dioxide emissions may have finally stabilized on a year-to-year basis following decades of rapid growth, but they have plateaued at a dangerously high rate. A rapid decline in yearly emissions would be needed to achieve the Paris agreement’s goals, but there have been no robust signs of decline.
“It's quite possible, even likely, that emissions will rise further,” said Stanford professor Robert Jackson, a scientist with the Global Carbon Project, which tallies climate pollution. “I doubt we'll ever see sustained growth again the way we did for the past decade.”
Even if all countries meet the pledges they made under the Paris agreement, fossil fuel burning wouldn’t be phased out quickly enough to achieve the goals of the agreement. Rules will be debated in Marrakesh designed to hurriedly improve those national pledges, testing the world’s current appetite for aggressively tackling warming.
“The heart of the accord is the process it establishes to periodically review countries’ progress toward meeting their commitments, and to ratchet up ambition over time,” said Alex Hanafi, a climate expert with the nonprofit Environmental Defense Fund. “The goal of the Marrakesh gathering is to maintain the strong momentum on climate action.”

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