U.S. Secretary of State John Kerry gestures as he speaks during a visit to Expo Milan in Milan, Italy, Oct. 17, 2015.
The stability of the world is directly linked to climate change and its impact on food security for billions of people, U.S. Secretary of State John Kerry said on Saturday.
In a speech to the Milan Expo, Kerry argued that unrest tied to climate change induced agricultural failure poses an international threat. The Milan Expo in Italy is focused on food security, and Kerry urged attendees to act quickly against climate change.
“Make no mistake: The implications here extend well beyond hunger,” Kerry said. “This isn't only about global food security, it's about global security period.”
Kerry said it was "not a coincidence that, immediately prior to the civil war in Syria, the country experienced the worst drought on record", sparking the migration of some 1.5 million people "that intensified the political unrest that was beginning to brew".
"I'm not suggesting the crisis in Syria was caused by climate change, obviously, it wasn't. It was caused by a brutal dictator who barrel bombed, starved, tortured, and gassed his own people. But the devastating drought clearly made a bad situation a whole lot worse," he said.
'Threat multiplier'
Kerry described climate change as "threat multiplier".
"Even if it doesn't ignite conflict, it has the ability to fan the flames and to make situations much more complicated for political leaders to deal with."
Kerry cited the mass migration to Europe as an example of a crisis provoked partly by climate change — which he warned will get significantly worse if large parts of the world become uninhabitable due to global warming.
FILE - Migrants walk along a street after they arrived by train in
Hegyeshalom, at the Austrian border, 169 km west of Budapest, Hungary,
Oct. 7, 2015.
Kerry urged world governments to act quickly against climate change because without such action, he said, "the horrific refugee situation we're facing today will pale in comparison to the mass migrations that intense droughts, sea-level rise and other impacts of climate change are likely to bring about.''
Upcoming UN conference
Kerry's call comes ahead of the U.N.'s conference in November aimed at securing a pact on greenhouse gases that would limit global warming to two degrees Celsius over pre-industrial times.
The White House has made tackling climate change a priority, despite stern opposition from the Republican-controlled Congress.
The last big push for a world climate deal was in Copenhagen in 2009. It nearly ended in a fiasco after rich and poor countries bickered over how to share the burden of addressing the problem.
Kerry is in Italy on the first leg of a three-nation tour of Europe that will also take him to France and Spain.
If Vatnajökull were melting at the same speed as the Greenland ice
sheet, it would be gone in ten years – and global warming in the
Arctic region has reached incredible levels, says Tómas Jóhannesson,
glaciological research group leader at the Icelandic Met Office.
Global warming is a cause for concern for many. The European Union, for instance, has set a target to limit global warming to 2°C this century, as compared to pre-Industrial Revolution temperatures. According to Tómas Jóhannesson, glaciological research group leader at the Icelandic Met Office, many scientists believe this target is unrealistic. Since 1980, temperatures in the northern hemisphere have risen by just under 1°C – and by much more in the Arctic region. Temperatures in Svalbard, Norway, have risen by 3-4°C, in Greenland by over 2°C, and in Iceland by just over 1.5°C. "These unbelievable increases are major news, particularly in Svalbard and Greenland," says Jóhannesson.
Global warming quickest in Greenland
The quickest temperature rises have occurred in Greenland, Alaska, Northern Canada and Siberia. Significant warming did not begin in Greenland until the mid-1990s, i.e. temperatures have risen by over 2°C in just twenty years. "This is a much quicker rise than anybody expected, even in the Arctic region," explains Jóhannesson. "The explanation is probably that a localised, natural change – which was due on the back of low rises in temperature in previous years – coincided with general global warming. Most people expect that, before long, the pace of warming in this region will slow down and approach long-term averages. When the current period of natural warming ends – and nobody expects it to last forever – a period of slower warming will commence."
That said, Jóhannesson adds that temperatures in the Arctic region could rise at double the rate of the rest of the world over the next 100 years. "There is general agreement that this means a wildly different climate for the Arctic region – including Iceland – bringing completely different conditions for animal and plant life."
Several causes of global warming
Global temperatures have always fluctuated. For instance, temperatures in the Arctic region are thought to have been much higher 6-8,000 years ago. "There are several other examples of warm times," Jóhannesson points out. "Temperatures in Iceland – and in most of the Arctic region – back in 1930-40 were about as high as they are now. The difference is that climate warming is occurring for different reasons now than in the past, i.e. by human influence. By this I mean emissions of greenhouse gases – if nothing is done about this trend, the world will continue to heat up more quickly than ever before."
According to Jóhannesson, it is difficult to forecast global warming for the next century, as it is not yet clear what the international community will agree upon in their efforts to reduce greenhouse-gas emissions. Some predictions assume similar or higher emission levels than now, others lower. Population growth is also a factor, and forecasts from the United Nations are used in this context. Jóhannesson indicates that temperatures in Iceland could rise by 2-3°C by the end of the century if little is done to control emissions, or by 1-2°C if radical action is taken. "These forecasts have not changed significantly in over twenty years," he says.
Glaciers are an accurate ‘thermometer’
Glaciers act as an accurate ‘thermometer’ and global warming obviously affects them. The years 2009-14 saw twice as much ice melt in Greenland as in 2003-09, and three times as much in Antarctica. "Around the year 2000, glacial input into the world’s oceans was highest from ‘small glaciers’, such as Iceland’s Vatnajökull and glaciers in Alaska, Patagonia and elsewhere," explains Jóhannesson. "Nowadays, the Greenland ice sheet pours more into the sea than all of these smaller glaciers put together. The small glaciers added 0.5-1 mm per year to the world’s seas, although there is a good deal of uncertainty about this figure. The Greenland ice sheet has now reached a figure of 1 mm per year, up from 0.5 mm per year just a few years ago."
According to Jóhannesson, scientists expect this trend to continue as long as the Arctic region continues to warm up.
He indicates that changes appear to be quickest where glaciers break off into the sea, as both sea temperature and pack ice in front of glacier ice tongues determine to a significant extent the rate of glacier melting. Reductions in pack ice also affect temperatures. Where before expanses of pack ice reflected sunlight away, open seas reflect less sunlight back into space and heat up.
Changes to run-off
What impact could this fast-melting ice have on Iceland? Jóhannesson’s first answer is glacial run-off. He also mentions possible changes in water course, e.g. water that previously flowed to a waterfall outside of the glacier could begin to flow elsewhere. Changes could also occur in courses of water on the outskirts of glaciers. The best example of this in Iceland is the Skeiðará river, which changed course in 2009 and merged with Gígjukvísl river. Lakes could form with run-off in different places to where glacier rivers traditionally flow from.
Furthermore, increased glacial melting could bring changes to glacier-edge lagoons and, in turn, to glacier river floods. Some lagoons may stop flooding while new ones begin. Floods could also become weaker as their flow out into lagoons, meaning all sorts of changes to water flows. If lagoons form on the edges of glaciers, sediment will settle, altering the deposits and colour of rivers. Other factors, such as fish migrations, may also be affected.
On top of all this, land rises when glacial pressure decreases. This can alter the coastline and have an effect on sea erosion. Jóhannesson gives the example of the harbour in Höfn, South Iceland, which is quickly getting shallower as the Vatnajökull glacier recedes. Land is expected to rise by more than one metre this century, which will make entering the harbour considerably problematic. "This is a big issue for the community," warns Jóhannesson, adding that in most places in Iceland sea levels are actually rising, since world sea levels are rising and the land is not being altered by changes in glacial pressure. Sea is encroaching on land rather than the other way round.
Vatnajökull gone in ten years
On the subject of the Greenland ice sheet, Jóhannesson explains that the glacier is shrinking and is therefore exerting less of a gravitational pull on the sea towards Greenland than before. "It is reasonable to expect the sea to retreat to some extent from Greenland, meaning sea levels will in many places drop or at least not rise as much as they otherwise would," he says. "This is not, however, a particular problem since in Greenland the land descends steeply into the sea. These changes will therefore not cause problems for harbours. Sea-levels around Iceland will also rise less than the world average for the same reason."
Ice is melting in Greenland at thirty times the rate in Iceland, according to Jóhannesson. "The Greenland ice sheet is shrinking by 350 m2 per year – that is one-tenth of the size of Vatnajökull, he explains. "This means that if Vatnajökull were melting at the same speed as the Greenland ice sheet, it would be gone in ten years – a striking statistic."
According to Jóhannesson, extensive research has been carried out into the effect of climate change on glaciers in Iceland. One study predicts that Langjökull, Hofsjökull and the southern part of Vatnajökull will all have disappeared in 200 years’ time. "Both the former Icelandic Nautical Agency and the current Icelandic Road and Coastal Administration are already taking such factors into account when designing ports and infrastructure," he explains. "Similarly, the National Power Company of Iceland bases the design and management of its hydropower plants on considerations of changes in glacial run-off. For instance, in recent times it has been possible to generate more energy from the Kárahnjúkar Power Station than it was originally designed for, i.e. the new operational situation has increased hydropower revenue. Shrinking glaciers also have an effect on the appearance of the land, tourism, and many other factors. These changes will require a lot of planning."
In November, nearly 200 countries meet in Paris for UN talks to agree a new climate deal. Find out below how their pledges - known as Intended Nationally Determined Contributions or INDCs in UN jargon - compare in our in-depth analysis of 14 key countries and blocs
Without new action on carbon emissions, this happens
This is why Paris is necessary. Developing countries still have a lot of developing to do – and that means big increases in emissions that would lock in dangerous global warming. That’s why, unlike the only previous international climate protocol, Paris will apply to rich and poor countries.
The European Union’s promised emissions cut will almost certainly be the most far-reaching climate offer on the table in Paris.
If
it is fully achieved, with no loopholes or carbon accounting tricks,
the EU can say that it is walking a path that offers a greater than 50%
chance of limiting global warming to the “safe” threshold of 2C.
Despite being the host of the UN summit that led to the Kyoto
protocol on climate change in 1997, Japanese negotiators will arrive in
Paris in November with an underwhelming plan of action for greenhouse
gas reductions.
Just as US president, Barack Obama, issued a call to arms
to save the climate “while we still can,” Japan announced modest carbon
emission reductions that drew criticism from environment campaigners
and earned it Fossil of the Day award from the Climate Action Network.
In a country famed for icy temperatures, the concept of global
warming is often greeted with jovial chuckling. While many in the
Russian political elite understand the seriousness of the problem, the
current economic downturn, and conventional short-term economic
thinking, means the political will to prioritise reducing emissions is
absent.
Russia’s greenhouse gas emissions did not grow in 2014,
as the country entered economic downturn, due to western sanctions and
the falling price of oil. In recent years, greenhouse emissions have
risen, but at a much slower rate than economic growth, mainly because
the economy has been restructured from heavy industry and manufacturing
towards resource extraction and services, since president Vladimir Putin
came to power in 2000.
Barack Obama pledged the second half of his presidency to fighting
climate change – even in the face of strong opposition from industry and
a Republican-controlled Congress.
The target Obama set ahead of
the Paris climate talks of a 26-28% cut in carbon pollution by 2025 from
2005 levels is proof of that commitment, experts said.
Canada put forward one of the weakest climate targets of any major
industrialised economy, which experts said was a direct result of the
Stephen Harper government’s promotion of the highly polluting tar sands
industry.
The Canadian government proposed to reduce greenhouse gas emissions 30% below 2005 levels by 2030.
Australia’s emissions reduction target for 2030 is lower than some
comparable developed countries, but the greatest scrutiny now is whether
the new prime minister, Malcolm Turnbull, can improve policies widely
regarded as inadequate to achieve it.
Before he was ousted in a leadership coup in September, the former prime minister Tony Abbott announced Australia would reduce emissions by between 26% and 28% of 2005 levels by 2030. Turnbull has since backed the pledge.
Abbott argued it put Australia “foursquare in the middle” of the pledges comparable economies will take to the United Nations meeting in Paris in December
and argued Australia’s higher population growth and the higher economic
costs of global climate action on coal exports should also be taken
into account.
“It’s better than Japan. It’s almost the same as
New Zealand. It’s a whisker below Canada. It’s a little below Europe.
It’s about the same as the United States. It’s vastly better than Korea.
Of course, it is unimaginably better than China,” Abbott said at the
time.
Pylons running from Liddell Power Station near Muswellbrook. Photograph: Tim Wimborne/Reuters
Others
disagreed. Bernie Fraser, the chairman of an independent government
advisory body – the Climate Change Authority (CCA) – which the Abbott
government had unsuccessfully sought to abolish, said the target put Australia “at or near the bottom of the group of countries we generally compare ourselves with”. Fraser has since resigned.
The CCA had recommended much deeper cuts of between 45% to 63% on 2000 when taken from the 2005 base year. The Climate Institute thinktank said
the target was not scientifically credible, because it did not
represent Australia’s fair share of the global task to limit warming to
2C (a goal the Australian government accepts), describing it as
“pathetically inadequate”.
But the focus is now on whether Turnbull changes Australia’s climate policies, which business leaders and environment groups say have little chance of meeting the new target.
Climate policy is one of the most contentious issues in Australian
politics and Turnbull lost the Liberal leadership when the conservative
parties were in opposition in 2009 because of his insistence that they
back the then Labor government’s economy-wide emissions trading scheme.
Abbott,
who wrested the Liberal leadership from him and went on to win the 2013
federal election, said at that time he thought the “settled science of
climate change was absolute crap”. The first bill introduced by the
Abbott government after the election victory was to repeal the emissions
trading scheme, which had been eventually legislated by Labor with the
backing of the Greens party.
The Abbott government also
tried – unsuccessfully – to dramatically reduce Australia’s target for
the uptake of renewable energy and to abolish agencies aimed at
commercialising and providing finance for clean energy. Abbott and key ministers said they
found wind turbines “utterly offensive” and “ugly” and promised to
appoint a special commissioner to investigate complaints about health
impacts of windfarms.
Turnbull has been forced to promise the
conservative wing of his party that he will not revisit that argument
and will stick with the coalition’s so-called “Direct Action” climate
plan, which sets aside $2.5bn for a competitive grants process to pay
for greenhouse gas abatement.
But it is anticipated he will bring a far less hostile approach to action on global warming.
He
could change other aspects of the policy – including “baselines” for
the biggest industrial emitters, which are scheduled to be set at levels
which would allow many to increase their greenhouse pollution and without the aim of forcing any reductions.
Coal is stockpiled in preparation for loading onto ships for export at the Newcastle Coal Terminal in Newcastle. Photograph: Ian Waldie/Bloomberg/Getty Images
Abbott
once described buying international carbon permits as being like
sending “money … offshore into dodgy carbon farms in Equatorial Guinea
and Kazakhstan”, but when announcing the new target he did not rule out
allowing offshore permits after a review of Australia’s policy in
2017-18. Turnbull could bring forward their inclusion.
The Labor
opposition has not revealed what post-2020 emissions reduction target it
would favour, but environment spokesman Mark Butler has said the
government’s target is not high enough. Labor has promised to
reintroduce an emissions trading scheme if it wins the general election
in 2017.
The government modelled the economic cost of its 2030
target. It showed the 26% target would shave between 0.2% and 0.3% from
Australian GDP in 2030, but the same modelling found that – based on similar assumptions, a 35% target would cut only 0.3% to 0.5% and a 45% target would cut between 0.5% and 0.7%.
Brazil’s promise to reduce total emissions by 2025 is a bold
political move that should allow the country once again to play a
leading role in climate negotiations.
As the first major developing nation to pledge an absolute reductions target
(rather than relative to GDP), Brazil will be in a strong position to
bridge the gap between rich and poor nations at the Paris talks in
December.
China is the world’s largest carbon emitter due to its voracious
appetite for coal to fuel its massive economy. For this reason, much
attention is on China ahead of the UN climate change negotiations in
Paris and its post-2020 climate action commitment was eagerly awaited.
China has changed its approach to cutting carbon emissions since the disastrous Copenhagen negotiations in 2009 when it was blamed for blocking an agreement.
The government is now taking the need to cut emissions seriously and
this is reflected in its submission to the United Nations. As part of
its pledge to reduce carbon emissions beyond 2020, China has said it
will cut its CO2 emissions per unit of GDP by 60-65% from 2005 levels by
2030.
India was a day late in its submission of its climate change plan to the UN, and was the last of 140 countries to do so.
The
delay was partly deliberate. The government of Narendra Modi waited
until the anniversary of the birth of the Mahatma Gandhi , the revered
independence leader and campaigner for a low-tech local model of
economic development based on village communities, to give their
announcement added resonance.
Indonesia’s pledge to cuts its carbon emissions by 29% by 2030
compared to current projections has been criticised for failing to
adequately address large-scale forest and peatland loss, which account
for the majority of its emissions.
Campaigners said the final submission to the UN is full of “empty words” that are too “vague” on deforestation.
Ethiopia was until recently a byword for African famine, drought and
absolute poverty. But the climatically vulnerable country where 10
million people rely on food aid and which is responsible for just 0.3%
of global carbon emissions will go to the Paris climate talks as a
leader of other developing countries, planning to hold its emissions and
to double the size of its economy by 2030.
Officials in the
ministry of the environment in Addis Ababa say they have no option but
to act on climate change. “Ethiopia did not cause [it]. But we are
confronted by the threat that it poses. It has the potential to
destabilise us and other countries in the Horn of Africa, bring more
fierce competition for water and other resources,” says a government
spokesman.
Mexico received international praise for being the first major developing country to submit its pledge to the UN on curbing greenhouse gas emissions ahead of the Paris summit.
Mexico
promised to start reducing emissions from 2026, with an unconditional
pledge that by 2030 they would be 22% lower than business-as-usual
projections. With conditions, the government said the reductions could
be 40%.
Morocco will host next year’s UN climate summit and is becoming an
Arab leader at the Paris talks in December. Earlier this year the north
African country, which is 95% dependent on Middle East oil and gas for
its energy, committed to spending $10bn (£6.5bn) of its own money to
make a 13% reduction in greenhouse gas emissions by 2030.
But it also pledged to cut emissions a further 19% if $35bn of additional money can be generated from UN climate funds, the private sector and other countries.
A composite image of the Western hemisphere of the Earth. Credit: NASA
An international team of scientists have identified potential 'tipping points' where abrupt regional climate shifts could occur due to global warming,
In the new study, published in Proceedings of the National Academy of Sciences (PNAS), the scientists analysed the climate model simulations on which the recent 5th Intergovernmental Panel on Climate Change (IPCC) reports are based.
They found evidence of 41 cases of regional abrupt changes in the ocean, sea ice, snow cover, permafrost and terrestrial biosphere. Many of these events occur for global warming levels of less than two degrees, a threshold sometimes presented as a safe limit. However, although most models predict one or more abrupt regional shifts, any specific occurrence typically appears in only a few models.
"This illustrates the high uncertainty in predicting tipping points," says lead author Professor Sybren Drijfhout from Ocean and Earth Science at the University of Southampton. "More precisely, our results show that the different state-of-the-art models agree that abrupt changes are likely, but that predicting when and where they will occur remains very difficult. Also, our results show that no safe limit exists and that many abrupt shifts already occur for global warming levels much lower than two degrees," he adds.
Examples of detected climate tipping include abrupt shifts in sea ice and ocean circulation patterns, as well as abrupt shifts in vegetation and marine productivity. Sea ice abrupt changes were particularly common in the climate simulations. However, various models also predict abrupt changes in Earth system elements such as the Amazon forest, tundra permafrost and snow on the Tibetan plateau.
"Interestingly, abrupt events could come out as a cascade of different phenomena," adds Victor Brovkin, a co-author from Max Planck Institute for Meteorology (MPI-M). "For example, a collapse of permafrost in Arctic is followed by a rapid increase in forest area there. This kind of domino effect should have implications not only for natural systems, but also for society."
"The majority of the detected abrupt shifts are distant from the major population centres of the planet, but their occurrence could have implications over large distances." says Martin Claussen, director of the MPI-M and one of the co-authors. "Our work is only a starting point. Now we need to look deeper into mechanisms of tipping points and design an approach to diagnose them during the next round of climate model simulations for IPCC."
The latest batch of rock dates released by the MIT geochronology team "inescapably" nails the link between the end-Permian Siberian Traps eruptions and Earth’s worst mass extinction, pointing to the critical role of greenhouse gasses in the catastrophe.
The link Seth Burgess and Samuel Bowring confirmed the long-hypothesized link by comparing new, high-precision dates from volcanic rocks with equally precise dates for the mass extinction measured from volcanic ash in sediments spanning the end-Permian boundary in China. By ensuring the same labs and chemical tracers were used in both sets of measurements, they were able to compare the dates at an unprecedented precision of 0.04% or better, even though the rocks sampled were from locations thousands of miles apart.
The Siberian Traps are an example of a rare geological phenomenon called a “Large Igneous Province” (LIP) which has been linked to 4 out of the “big 5” mass extinctions since animals evolved. The new timeline enables science to zoom in to the details of the terrible events 252 million years ago, in which more than 90% of marine, and some 75% of land life went extinct.
Timeline of Earth’s worst mass extinction. Redrawn and simplified from Burgess & Bowring 2015, annotations and photos added.
The timeline
The LIP began with explosive eruptions around 252.3 million years ago, as magma and lava encountered waterlogged, swampy terrain. These eruptions blanketed the region in volcanic ash, in some areas building to a kilometer thick. Then at 252.24 million years ago, lava flows took over: curtains of bright lava gushed from fissures, emitting CO2 and SO2, before flowing through lava tubes to advancing lava fronts. Fully 2/3 of the entire Siberian Traps lava sequence erupted this way over 300,000 years, building to 4 km thick of stacked lava flows that form the “traps” landscape of the Siberian Traps today. That’s some 3 million cubic kilometers of magma – with associated gasses - erupted before and at the onset of the mass extinction.
The end-Permian mass extinction began towards the end of those lava eruptions, at the same time as a huge spike in the carbon isotope balance, indicating that massive amounts of CO2 and/or methane were released into the atmosphere and oceans from an exponentially growing pool rich in carbon-12. The rapidity of this isotope “excursion” strains the limits of even the new dating resolution, with a duration somewhere between 2,100 and 18,800 years. The smaller of those numbers is a mere 2 complete ocean circulations at today’s rates, fewer if circulation was more sluggish in the Permian. This matters because we expect abrupt global warming and ocean acidification if CO2 emissions overwhelm the oceans’ capacity to process them, as explained in this article.
Since life preferentially stores carbon-12 over carbon-13, this suggests that a large reservoir of once-living carbon was rapidly converted to CO2. Alternatively, it might indicate a mantle sourceunusually rich in carbon-12.
The mass extinction unfolded for about 61,000 years into the early Triassic. The uncertainty on the extinction episode means it might have been as short as 13,000 or as long as 109,000 years – a timespan during which complex life on Earth was nearly wiped out by the deteriorating environment and climate change.
Over the years leading into the mass extinction the oceans gradually became more acidic, resulting in the loss of shelly, carbonate producing animals, and leaving sea beds dominated by sponges. Then at the carbon isotope excursion even the sponges disappeared as the environment became heavily polluted. The terrestrial extinction happened at the same time, as acid rain fell and global temperatures soared some 10°C. As the seas warmed they became starved of oxygen so that even the worms that burrowed in the seabed disappeared. Temperatures remained high well into the Triassic, and it took 10 million years for biodiversity to recover.
As Burgess and Bowring point out, these symptoms: “…all point to anomalously high atmospheric pCO2 as a critical driver of both terrestrial and marine biotic crises”
The mystery
The mystery is: what triggered the massive carbon release in the final few millennia of the eruptions, rather than any time in the preceding 300,000 years? As Burgess and Bowring say: “The enormous total volume of LIP magmas might be less important than an aliquot of the total, erupted/emplaced in a very restricted interval.”
It may be that the progressive degradation of the Permian conditions brought the environment to a tipping point, such as the destabilization of methane clathrates in the oceans. But a recent study suggests that by the end-Permian reserves of marine clathrates were largely tapped-out.
Burgess and Bowring suggest an alternative scenario: “Early sill intrusion into, and magma transport through an untapped, volatile-rich basin may be this critical aliquot."
They dated the Noril’sk 1 underground igneous intrusion - the oldest found anywhere in the Siberian Traps – as beginning around same time as the carbon isotope excursion. Noril’sk 1 marks the beginning of a new phase of the eruptions – the injection of many underground sheets of magma (“sills” and “dikes”) into the Tunguska sedimentary basin, a thick sequence of sedimentary rocks containing fossil fuels. Some sills reach 350 meters thick and extend great distances, and cumulatively the intrusions exceed 2 million cubic kilometers of magma. Svensen et al showed in 2009 that these sills baked coal, oil and natural gas, salt, limestone, and organic-rich shales in the sediments, generating large volumes of methane and CO2, as well as a cocktail of noxious gasses, acids, ozone-eating chemicals and coal fly-ash. These gasses exploded into the atmosphere through thousands of pipe eruptions across Siberia, belching columns of gas and pollutants from vents up to 1.6 km wide, leaving behind mineral-rich pipes that are mined for iron ore today.
Earlier this year Fristad et al published a study of the carbon chemistry of one of those pipes, which showed that the carbon involved in its formation was indeed rich in carbon-12, strongly linking Permian pipe eruptions with the massive release of carbon-12 recorded in the isotope excursion.
Noril’sk 1 was amazingly long-lived, having 3 distinct magma injections over some 267,000 years. But many of the observed Siberian sills and dikes are dated to after the mass extinction, a time when the carbon isotope curve shows only minor variation. It may be that the sediments had limited reserves of carbon to bake-off. Within a few thousand years their fossil fuel reserves may have been exhausted. Then and now
As I outlined in this earlier article, emission rates matter a lot when it comes to our oceans’ ability to process them. Some LIPs, like the Paraná-Etendeka LIP, erupted slowly without causing environmental destruction and global climate change. These new dates suggest that the initial phase of the Siberian Traps had a relatively modest effect on the global environment, but later on during the eruptions, probably when widespread sill intrusions occurred and greenhouse gasses from baking of sediments were added to the load, this appears to have overwhelmed the already-stressed environment.
The irony is that back in the Permian the combustion of fossil fuels contributed to global warming and an environmental catastrophe so extreme that it came close to extinguishing complex life. Today we are embarking down a similar path, emitting at rates probably faster than in the end-Permian, even though our total emission quantities are smaller.
As new dates keep resolving the timeframes for these epoch-changing events in Earth’s past to ever-briefer intervals, their similarities with modern climate change increase. If Earth responded in a similar manner several times in its past, it is crucial that we focus research on understanding just how similar our modern path is, and how far along it we have already travelled, because the destination isn’t exactly a picnic spot.
Delegates attend the opening of the Intergovernmental Panel on Climate
Change (IPCC) at the Tivoli Congress Center in Copenhagen on Oct. 27,
2014. (Keld Navntoft/AFP/Getty Images)
Let’s face it: Climate science isn’t always the easiest subject to explain to non-scientists. However, the political charge surrounding global conversations about climate change makes it all the more important to communicate the science to the general public as clearly and accurately as possible. Unfortunately, new research suggests that the world’s foremost body dedicated to reviewing and communicating climate science may be falling short in this area.
The U.N.’s Intergovernmental Panel on Climate Change holds some of the greatest responsibility when it comes to communicating climate science, if only because it is so high-profile and regarded as the gold standard of climate science. Every five to seven years or so, the IPCC releases an assessment report reviewing the recent research of thousands of climate scientists around the world. Each assessment report is released in a series of sections devoted to specific topics, and each section is accompanied by a “summary for policymakers” (SPM),which is intended to summarize the findings for a non-scientific audience, particularly government officials who can use the information to help create new climate policies.
The reports also tend to receive extensive coverage in the media, and more so as the years go on and the international focus on climate change continues to sharpen. This means that the IPCC’s assessments are reaching a bigger audience than ever before.
But although the IPCC’s reach has been expanding, its reports have not necessarily become easier for the layperson to understand — in fact, just the opposite, argues a new study, published today in Nature Climate Change. The study uses analysis software to find that the readability of the IPCC’s SPMs has generally deteriorated over time, even as media coverage of it has become increasingly readable.
“We started looking into IPCC communications because we (in line with many other people) had the feeling that IPCC summaries for policymakers are quite simply difficult to read and to understand,” said Ralf Barkemeyer, an associate professor at the KEDGE Business School and the study’s lead author, in an e-mail to The Post. Although the organization does employ a communications staff, the IPCC has been criticized in the past for problems with communication, not only when it comes to the language of the reports, but also when it comes to relaying its internal decision-making processes to the public.
Barkemeyer and his colleagues used two different tools to analyze the texts of the SPMs and their corresponding media coverage: an algorithm which assesses readability and a separate software which assesses how optimistic a text is in tone. They applied these analysis tools to four types of publications: the IPCC reports and related articles in popular science publications (namely, the journals Science and Nature), newspapers and tabloids.
In general, the IPCC reports were the least readable and newspapers and tabloids were the most readable, with popular science publications occupying a middle ground between them. For instance, one of the SPMs from the latest assessment report includes such complex phrasing as, “Mitigation scenarios reaching concentration levels of about 500 ppm CO2eq by 2100 are more likely than not to limit temperature change to less than 2 °C relative to pre-industrial levels, unless they temporarily ‘overshoot’ concentration levels of roughly 530 ppm CO2eq before 2100, in which case they are about as likely as not to achieve that goal.”
Media coverage was also generally more pessimistic in tone than the IPCC reports themselves — perhaps unsurprisingly. As the authors note, “Newspapers need to turn a piece of scientific information into a piece of news, which among other aspects requires bringing future climate change consequences into the sphere of immediate interest of the reader. Using emotive language is one of the journalistic strategies for bringing the future into the immediate.”
What was surprising, according to Barkemeyer, was that there was no improvement in the SPMs’ readability as more reports were released over time. “Given the huge amount of attention that has been paid to this topic in recent years, we would definitely have expected to see some improvements over time,” Barkemeyer said in his e-mail — but in fact, some sections of the reports seemed to become less readable as time went on.
The assessment reports are typically released in different sections, which address specific topics and are published by three designated committees, or “working groups,” each of which also provides its own summary for policymakers. The researchers found that while the readability of working group I’s SPMs remain fairly stable over time, working groups II and III deteriorate over time. In contrast, readability for newspapers and popular science magazines did increase as time went on, peaking in 2007.
The authors also found that political tensions may play a role in an SPM’s readability. Every time an assessment report is released, it goes through a round of edits known as the plenary process. As the authors note, “The plenary process is important to the SPM because its ‘approval’ means that the material has been subjected to detailed line-by-line discussion and agreement between government delegates and authors.” Yet when they compared the SPMs’ readability pre- and post-plenary, they found that the plenary process actually lowered readability in five out of eight cases.
“We found a strong relationship between political mood and SPM readability,” the authors write. They assessed political mood by examining reports on the plenary processes from the Earth Negotiations Bulletin reporting service. When political tensions were running high, the readability went down after the plenary process was complete.
Low readability is a problem if it means that the reports aren’t clear to the policymakers they’re meant to inform, Barkemeyer said. “Hard-to-understand summaries are more likely to be misunderstood – and it will then be necessary that intermediaries ‘translate’ information from these summaries into a language that policymakers can understand,” he wrote in his e-mail. “Thus, the communication process becomes more complicated, with more actors involved, and a higher likelihood of misinterpretations and disagreements along the way.”
“There is no doubt that more needs to be done to make IPCC reports more readable and accessible,” said an IPCC statement on the study e-mailed to The Post. “The newly elected Chair of the IPCC, Hoesung Lee, has made this point and we are determined to tackle it. The challenge is to do it in a way that does not damage the scientific rigor and robustness of the reports, or allow important nuances in them to be lost.”
The IPCC has already made some steps toward improving its communication, the statement noted. “The previous Session of the IPCC, in Nairobi in February this year, took decisions to enhance the usability of IPCC reports, for instance by using digital technology to share and disseminate information, and to draw on specialists (such as science writers and graphical designers) to enhance the readability of IPCC reports. The IPCC is holding an expert meeting in February 2016 to discuss lessons learned from communicating the Fifth Assessment Report, and when the scoping process for the Sixth Assessment Report starts next year the Panel will have an opportunity to tackle this.”
But it may be that the low general readability scores indicated in this study don’t actually pose that much of a problem for the documents’ intended audiences, said Michael Oppenheimer, a professor of geosciences and international affairs at Princeton University who was a lead author in the IPCC’s fourth assessment report and a coordinating lead author on the IPCC’s special SREX report on extreme climate events and disasters.
“This and other reviews of IPCC communication don’t emphasize enough that the target is primarily governments (for example, the staff of EPA or DoE or an environment ministry), not the average newspaper reader (or even a scientifically attuned reader),” Oppenheimer said in an e-mail to The Post. “The main point of the four-day plenaries which produce the SPMs is so that the material drafted by scientists can be converted to a form that is understandable to governments while still accurately reflecting the science.”
He added: “One might ask this: If, as the study finds, newspapers and other intermediaries are doing a progressively better job of communicating IPCC findings to the larger public, and if governments are happy with the SPMs, is there really a problem?”
Still, it remains unclear whether the science in the documents is actually being interpreted correctly by the policymakers and journalists who read them. On this front, Oppenheimer agrees with the authors that improvements could still be made to the IPCC’s writing teams in order to ensure that the documents are likely to be understood correctly by their readers.
One option would be to hire professional science communicators to help write the reports, Barkemeyer said. But, he cautioned, “potential benefits could be outweighed by the addition of yet another set of actors in the process, potentially distorting and politicizing the original voice of the scientific panel.” A simpler course of action could be to simply provide science communication training for the reports’ existing authors. A U.S. based climate communication group has already begun providing such a service for U.S. climate reports. A team of experts from the organization served as communication advisers on the 2014 U.S. National Climate Assessment in order to improve its readability and accessibility to the general public.
In any case, the increasing urgency of international efforts to combat climate change, along with corresponding growth in media coverage and public interest, means the need for effective science communication will only become more relevant as time goes on.
And while the authors note that the IPCC is already aware of the challenges associated with translating climate science to a lay audience, and has taken steps over the years to improve its communication, Barkemeyer concludes: “Our findings illustrate that there is still a lot of room for improvement.”
The 2015 Arctic sea ice summertime minimum — which was 699,000 square
miles below the 1981-2010 average. A new study cites Arctic sea ice
collapse as a possible ‘abrupt’ consequence of climate change. (NASA’s
Goddard Scientific Visualization Studio via Reuters)
It has been quite the week for climate change news: We’ve learned that scientists can now quantify the United States’ expected levels of inundation by rising seas, that droughts in the Amazon could triple, and much more.
But the most troubling research — depending, that is, on how you interpret it — may have appeared in a less-noticed, first-of-its-kind study just published in the influential Proceedings of the National Academy of Sciences. In it, the researchers attempted something that seems never to have been successfully done before. Namely, they mined the data from a large suite of computerized climate change simulations, or models, to determine how often they produced abrupt and disruptive changes in a few decades or even less — surely the most feared impact of climate change.
The result — that out of 37 abrupt changes detected in these climate simulations, fully 18 of them occurred at temperature levels less than 2 degrees Celsius of warming — is simultaneously dramatic and yet also difficult to assess. Models, after all, are mathematically sophisticated simulacra that embed scientists’ best current physical understanding of how the Earth system and its components work, but still should not be confused with reality.
Nonetheless, the authors — led by Sybren Drijfhout, a professor at the Royal Netherlands Meteorological Institute — assert that their results represent a sign of how unstable the future could really be, even before we reach warming levels of 2 degrees Celsius above pre-industrial levels (often thought of as a kind of guardrail in international climate negotiations). “It is likely that the Earth system will experience sharp regional transitions at moderate warming,” they write, “although the prediction of any particular event has a very high uncertainty.”
So what’s going on here — and should we really believe this? Mining models for major disruptions. The study — which Drijfhout undertook with a large team of researchers at institutes in Britain, the Netherlands, Germany and France — is in effect a massive “big data” inquiry into an urgent mystery about climate change. That mystery is this: When, precisely, can a relatively slow and steady rate of global warming trigger abrupt or sudden shifts in particular regions or Earth systems?
The topic has been much discussed — but also remains very murky. So to examine it in a new way, the researchers looked at the results of no less than 37 separate computerized climate change simulations, or models, which were used in the U.N. Intergovernmental Panel on Climate Change’s 2013 assessment report of the state of climate science. Each model’s results were examined out to the year 2100 — or farther, in cases where that was possible — under different assumptions about levels of greenhouse gas emissions, and resulting planetary warming.
In doing this, the work is entering new territory. “There has been no systematic study of the potential for abrupt shifts in state-of-the-art Earth System Models,” the research noted, calling the paper “a first step toward a robust assessment of abrupt change.”
A high-resolution global atmospheric modeling run on the Discover
supercomputer at the NASA Center for Climate Simulation at Goddard
Space Flight Center in Greenbelt, Md. (NASA/Goddard)
And sure enough, the models did produce many abrupt changes — but they were also rarely in agreement with one another. Some changes — for instance, a massive oceanic algal bloom in the Indian Ocean in the next century, which only appeared in one model — are dismissed by the researchers as a possible fluke. “That’s the one we are really most unsure about,” says Drijfhout.
On the other hand, other changes that showed up more frequently are precisely the types of things that scientists have long forecast might result from a warming of the climate. For instance, multiple models showed rapid collapses of Arctic sea ice, particularly in extreme global warming scenarios. And multiple models also produced partial or full shutdowns of circulation in the North Atlantic— a change that sometimes occurred for only moderate levels of warming (less than 2 degrees Celsius above pre-industrial levels).
“A striking feature is that the majority of abrupt transitions occur in the ocean-sea ice system, implying that this Earth system component is more prone to abrupt change than other components,” the research added. “These are very nonlinear processes that are reasonably well resolved in the models,” says Drijfhout — suggesting that if they turn up again and again, they may be something that can really happen in the real world. Other experts react. But here, perhaps, we should pause. Models are not predictions of the future — they’re more about understanding than about forecasting. And when an abrupt change shows up in just one model but not others, that could be simply due to the equations embedded in that particular simulation. Indeed, “no type of abrupt shifts occurs in all models,” the authors say.
Researchers asked to look at the study by The Washington Post offered some criticism, while also noting that the research certainly has consistencies with other evidence about abrupt climate changes. Until now, such work has largely been based on studies of the Earth’s past using so-called “proxy” evidence like ice cores or ocean sediments.
“As the authors note, it’s unclear whether these events are related to specific simplifications or perhaps even bugs in the codes, and without some consistency across models it’s hard to make any useful predictions,” said Gavin Schmidt, director of the Goddard Institute for Space Studies at NASA — which runs one of the models in question — by e-mail. “The places where most of these events occur are not surprising of course — the North Atlantic stands out.”
A similar take came from Richard Alley, a glaciologist at Penn State University who chaired a National Academy of Sciences panel on abrupt climate change. “Many questions exist about the ability of models to simulate ‘tipping points’ or abrupt changes accurately,” Alley said. “But the paleoclimate record shows clearly that such abrupt jumps have occurred, and this new paper shows that they are fairly common and widespread in the modeled climate system.”
The most critical take came from Kevin Trenberth, a climate researcher at the National Center for Atmospheric Research in Boulder, Colo. “I don’t find anything in this paper surprising or very illuminating,” he said by e-mail. “The paper does not validate the models to be able to say that any of them are realistic or likely. It is likely that some of these are more the result of model flaws. But it is a start,” Trenberth added.
Drijfhout said by e-mail that he agrees that climate models have not been validated based on their ability to capture abrupt changes — rather, he argues, they are validated based on their ability to capture the present climate and even “tuned” to be good at this. “There is consensus that climate models tend to be more stable than the real climate,” he said in his e-mail. For this reason, Drijfhout believes that models may underestimate its real instability and capability for abrupt shifts.
“In general there seem to be more missed cases than false alarms,” he said.
It’s also important to note that the simulations were not capable of detecting one possible abrupt shift that worries many climate scientists right now — the potential for a collapse of the West Antarctic ice sheet. “They are clearly correct in noting that some potential abrupt events aren’t possible in this class of models — no ice sheet components, or sub-surface methane hydrate routines,” noted Gavin Schmidt, director of the Goddard Institute for Space Studies at NASA, by e-mail.
In the end, the most striking finding from the study remains how many abrupt shifts occur — at least in the models — with relatively modest levels of warming. Granted, the paper also acknowledges that abrupt changes were most likely to occur at the highest warming scenarios.
“There is of course a certain tendency for the whole climate system to become more unstable when the warming gets larger,” said Drijfhout, “but we cannot say, ‘as long as it’s this and this much, nothing will happen.’ Every .1 or .2 degrees in temperature is as dangerous as any other, I would say. And that’s the main message of this exercise, or this paper.”
It remains to be seen how many other scientists agree with this assessment — and whether through future research, they can alter or improve on our abilities to detect truly abrupt climate change scenarios with modern computer simulations.
