The best shot at large-scale climate action under the Trump administration might lie with a lawsuit set to go to trial early next year.
The plaintiffs pose with climatologist James Hansen (top, third from left) and two attorneys. Clayton Aldern/Grist
Juliana v. United States has a plot suitable for a Disney movie:
An eclectic group of 21 kids (and their lawyers) fighting to save the
world by forcing the federal government to adopt a science-based plan to
reduce emissions. Their lawsuit got a boost this past week when climate
scientist James Hansen published a paper in support of their cause.
The time may be right for Juliana
and other lawsuits like it to gather real momentum, paving the way for
meaningful victories, says Michael Burger, executive director of the
Sabin Center for Climate Change Law at Columbia University. He says that
a "groundswell of litigation" could put "real pressure" on industries
and governments to pay for local adaptation projects and make firm
commitments to reduce emissions, all within Trump's first term.
Legal experts say Juliana
has helped open a new front in the battle against climate change in the
United States and around the world. It's the culmination of years of
legal strategizing by Our Children's Trust, the advocacy group that
helped organize the effort. Our Children's Trust has brought related
suits in all 50 states, as part of a buckshot strategy to get one of them to break through.
"This
case is especially crucial in the fight against climate disruption,"
says Kassie Siegel, director of the Center for Biological Diversity's
Climate Law Institute. Cases like Juliana, she says, empower young people to advocate for their rights, and that "drives social change."
The buzz about Juliana
comes amid a flurry of legal challenges to the Trump administration's
efforts to dismantle environmental rules. Just this week, a series of lawsuits
were filed in California as a direct challenge to the oil industry on
climate change grounds, using a legal theory similar to the landmark
tobacco industry lawsuits of the 1990s. The administration's quest to
roll back or reverse pending Obama-era EPA regulations is also getting
blocked in the courts.
When it comes to climate change, "so far, the Trump administration is losing more frequently than it's winning," says Burger.
At the heart of this suit is the principle of intergenerational equity. In essence, the 21 plaintiffs in Juliana
say that the federal government's refusal to take serious action
against climate change unlawfully puts the well-being of current
generations ahead of future generations.
This argument might have helped spur legal action abroad, too. Since Juliana was filed in 2015, similar lawsuits have been brought by youth in Pakistan, New Zealand, and India, Burger says.
"Worldwide, there is a great deal of interest in the Juliana
case not just because of the practical outcome that it might or might
not achieve, but because of what it represents," he says. "Deeply held
values about environmental protection, about intergenerational equity,
about the need to address climate change — these things can be linked to
specific legal rights embodied in constitutions or in common law."
So far, the courts agree. In November, they scored their first major victory,
when a federal district court allowed the suit to go to trial. Judge
Ann Aiken set a judicial precedent in her decision, ruling that climate
change may pose an unconstitutional burden on younger generations. "I
have no doubt that the right to a climate system capable of sustaining
human life is fundamental to a free and ordered society," she wrote.
Late last month, a trial date for the Juliana
case was scheduled for next February in Eugene, Oregon. It's sure to
set a dramatic spectacle of the kids and their lawyers on one side of
the room against representatives of the Trump administration on the
other, with the future of the climate on the line.
In his paper published on Wednesday, Hansen — whose granddaughter Sophie Kivlehan is a plaintiff in the case — presented an updated scientific basis
for the suit's claims. The new study, which has 14 coauthors from
around the world, concludes that the burden climate change has placed on
younger generations is now so huge that continuing on a high-emissions
scenario would cost a minimum of $89 trillion (and as much as $535
trillion) to clean up by the end of this century. And that cleanup job
would rely mainly on the still-unproven technology of negative emissions
— literally sucking carbon dioxide out of the atmosphere.
Such a
burden "unarguably sentences young people to either a massive,
implausible cleanup or growing deleterious climate impacts or both," the
paper argues. The best alternative, Hansen says, is a court-ordered
mandate to reduce emissions now.
After decades working as a NASA climate scientist and at times being politically pressured into silence, Hansen quit his post in 2013 in part to help build the scientific evidence backing the Juliana
case. "It's hard to solve this politically," he said on a conference
call with the media this week. "That's why we need to take advantage of
the fact that the judiciary is less subject to that pressure."
To be sure, the ultimate success of Juliana
hinges on the composition of the Supreme Court, if the case makes it
that far. That fact makes Burger and his colleague, Michael Gerrard,
less optimistic. "I can't foresee a scenario where there are five votes
to uphold such a ruling," says Gerrard. Burger called success in a
Supreme Court during Trump's first term "a near impossibility."
But
victory in the Supreme Court isn't the only objective for the kids and
their lawyers. This is a trailblazing case, designed to pave the way for
future success of other cases, too.
"This is strategic impact
litigation," says Burger. "As you can see from the global interest, it's
already had a real impact. It's starting to shape the conversation
about climate change."
When it comes to convincing climate change deniers, Al
Gore says, "Mother Nature is more persuasive than the scientific
community." Claire Harbage/NPR
Former Vice President Al Gore helped shape the conversation about climate change with An Inconvenient Truth. Now he's back with a sequel — called An Inconvenient Sequel: Truth to Power, due out next month —and it follows Gore as he continues the crusade he made famous with that first film.
The
movie shows Gore standing in Miami floodwater, flying over imploding
boulders of ice in Greenland and in Paris — trying to push the climate
agreement over the finish line.
President Trump, however, promised last month to undo that victory when he announced plans to pull the U.S. from the Paris climate accord.
"I did my best to convince him to stay in the Paris agreement," Gore tells NPR's Steve Inskeep in one of two recent Morning Edition interviews. "And I thought that there was a chance he would come to his senses, but I was wrong."
Still, Gore is hopeful about reversing the effects of global climate change.
"[O]ne
of the big differences between today and a decade ago is that we do
have the solutions now," he says. Renewable energy like solar and wind
electricity, he says, have evolved just like other technologies such as
mobile phones and TVs so that "when production scales up they come down
even faster in cost."
The first clip from the sequel to 'An Inconvenient Truth'. Paramount Pictures
Interview Highlights On recutting the movie to address President Trump's withdrawing of the Paris climate accord
We
always anticipated that we could not end the movie until we realized
who was going to win the election and what would happen thereafter. And I
will tell you that when President Trump made his announcement that the
U.S. will pull out of the Paris agreement I was deeply concerned that
other countries might use that as an excuse to withdraw themselves. But
I've been gratified that the entire rest of the world has doubled down
on their commitments to the Paris agreement and that here in this
country so many governors and mayors and business leaders have stepped
up to fill the gap and say "We're still in Paris." And I really think,
and the scientists think now as well, that we have an excellent chance
of meeting the commitments that former President Obama made in the Paris
agreement regardless of what Donald Trump says. On whether he thinks Trump believes in human-caused climate change
I don't know. I have heard him say different things. I've heard him
say in public things that would lead you to believe that he doesn't
believe in it. But the scientific community has been virtually unanimous
for a couple of decades and now there's a new participant in the
debate: Mother Nature. The other big change from 10 years ago is that
these climate-related extreme weather events are way more common —
unfortunately way more destructive. Here in the U.S. we've had 11
once-in-a-thousand-year events in the last seven years. Last year was
the hottest year globally ever measured. The second hottest was the year
before, the third hottest was the year before that. And Mother Nature
is more persuasive than the scientific community.
On those who dismiss climate change science because they've lost faith in experts
I
think that one cause of this populist authoritarianism that we've seen
not just in the U.S. but in Poland and Turkey and the Philippines and in
Hungary ... is that the expert blueprint for globalization that has
been touted for quite some time has caused those who feel left behind to
feel real anger that middle-income wages have stagnated for decades and
I think that generalized anger at how things are going extends over
into a vulnerability to listen to demagogic claims that the scientific
community doesn't know what it's talking about when they warn us of the
climate crisis.
On climate change's role in the 2016 election for Hillary Clinton
I
know the events I did for [Hillary Clinton] in the 2016 election evoked
a powerful response. I didn't see any other events that were devoted to
climate so maybe I missed that. I think that a lot of national politicians are told by their
pollsters and experts that they ought to focus on other issues, but I
think that's changing quite a bit. And I think that the partisan divide
is now fading on climate, I really do. I think the Democratic
Party should focus much more on [climate change]. And I believe that's
beginning to happen. If you look at Jerry Brown in California, Jay
Inslee in the state of Washington, Andrew Cuomo in the state of New York
and many others, we're now beginning to see a surge of interest in
people who want to get away from the fossil fuel utilities, they want
energy freedom, they want energy choice, and I think it will be a much
bigger political plus in the years to come.
Links
Watch the first clip from the sequel to 'An Inconvenient Truth.' Paramount Pictures.
USA TODAY NETWORK
A new global temperature baseline casts doubt on humanity's ability to meet the Paris target
Credit: MamiGibbs Getty Images
The temperature baseline used in
the Paris climate agreement may have discounted an entire century's
worth of human-caused global warming, a new study has found.
Countries in the Paris climate agreement set a target of keeping
warming below 2 degrees Celsius by curbing carbon emissions compared to
their preindustrial levels. But a new study shows that the preindustrial
level used in the agreement, based on temperature records from the late
19th century, doesn't account for a potential century of rising
temperatures caused by carbon dioxide emissions. Accounting for those
gases, released from about 1750 to 1875, would add another one-fifth of a
degree to the baseline temperature, the study found.
Published yesterday in Nature Climate Change, the research
suggests there's less time than previously believed to address global
warming, said Michael Mann, a climatologist at Pennsylvania State
University.
The study estimates that there may have already been 0.2 degree
Celsius of warming, or 0.36 degree Fahrenheit, built into Earth, he
said. That means the Paris Agreement would have to be more aggressive,
according to the study, which was also written by researchers from the
universities of Edinburgh and Reading in the United Kingdom.
“When you take that into account, it turns out we have 40 percent less carbon to burn than we thought we had,” Mann said.
When it comes to climate change science, researchers typically use
atmospheric carbon dioxide levels from the late 19th century as a
guideline, because that's when instrumentation was developed to
accurately measure temperatures. Researchers use models that combined
observed temperatures with simulated sea surface temperatures and
surface air temperatures to determine temperatures from 1401 to 1800.
The new baseline casts doubt on humanity's ability to meet the Paris
target of holding temperatures below 1.5 to 2 degrees Celsius above
preindustrial levels.
“The probability of exceeding the thresholds and timing of exceedance
is highly dependent on the pre-industrial baseline,” the authors wrote.
Mann cautioned that there is still time to stave off the worst
effects of warming, and that the Paris Agreement is the best path to get
there. Still, he said, the study suggests the world's carbon budget —
the amount of carbon dioxide the world can burn while keeping global
temperatures below 2 degrees — may be smaller than nations realize.
The advent of the internal-combustion engine sparked a major release
of carbon dioxide into the atmosphere that has warmed the Earth. The
Paris climate accord is the broadest attempt in human history to limit
those emissions. Re-establishing a new baseline would put more pressure
on countries around the world. The study came after Trump announced he
was withdrawing the United States from the Paris Agreement in order to
get a “better deal.”
Before the age of industrialization, the amount of atmospheric carbon
dioxide was about 280 parts per million (ppm), scientists have
determined. They measured air bubbles frozen in Arctic ice to ascertain
that number. The early decades of industrialization, fueled by economic
growth in Europe, may have added 30 to 40 ppm of carbon dioxide to the
atmosphere, according to Mann.
Now, atmospheric CO2 is rising at a record pace and is already at 410
ppm. It's expected to climb for decades. A growing body of research
suggests that the continuing rise in atmospheric CO2 could eventually
make some places on the planet uninhabitable, cause sea levels to swamp
coastal cities and lead to millions of refugees.
“The Paris commitments were seen as at least getting us on to the
right path and putting in place a framework where we could tighten the
framework in the years ahead,” Mann said. “Our studies suggest it's even
more urgent than we might have thought, because Paris, at least by this
measure, doesn't even get us halfway there. It gets us a third of the
way there.”
The global pact is supposed to review the best available science
every few years to inform progress toward limiting global temperature
rise. The study released yesterday is exactly the type of research that
could inform future negotiations, said Andrew Light, a distinguished
fellow at the World Resources Institute and a former senior climate
change adviser in the Obama administration.
“There has always been a strong tie between the scientific community
and the negotiations process,” he said. “The forum where most of this
stuff gets hashed out is the IPCC [the Intergovernmental Panel on
Climate Change] ... [and] there will be more of an ongoing opportunity
for parties to think about whether or not they need to revise their
targets in response to this.”
Reprinted from Climatewire with permission from E&E News. E&E provides daily coverage of essential energy and environmental news at www.eenews.net.
A young, fit US soldier is marching in a Middle
Eastern desert, under a blazing summer sun. He's wearing insulated
clothing and lugging more than 100 pounds of gear, and thus sweating
profusely as his body attempts to regulate the heat. But it's 108
degrees out and humid, too much for him bear. The brain is one of the
first organs affected by heat, so his judgment becomes impaired; he does
not recognize the severity of his situation. Just as his organs begin
to fail, he passes out. His internal temperature is in excess of 106
degrees when he dies.
An elderly woman with
cardiovascular disease is sitting alone in her Chicago apartment on the
second day of a massive heatwave. She has an air conditioner, but she's
on a fixed income and can't afford to turn it on again—or maybe it broke
and she can't afford to fix it. Either way, she attempts to sleep
through the heat again, and her core temperature rises. To cool off,
her body's response is to work the heart harder, pumping more blood to
her skin. But the strain on her heart is too much; it triggers cardiac
arrest, and she dies.
Such scenarios could
surely happen today, if they haven't already. But as the world warms due
to climate change, they'll become all too common in just a few
decades—and that's according to modest projections.
AFP/Getty Images
This is not meant to scare you quite like this month's cover story in New York magazine, "The Uninhabitable Earth." That story was both a sensation and quite literally sensational, attracting more than two million readers
with its depiction of "where the planet is heading absent aggressive
action." In this future world, humans in many places won't be able to
adapt to rising temperatures. "In the jungles of Costa Rica, where
humidity routinely tops 90 percent, simply moving around outside when
it's over 105 degrees Fahrenheit would be lethal. And the effect would
be fast: Within a few hours, a human body would be cooked to death from
both inside and out," David Wallace-Wells writes. "[H]eat stress in New
York City would exceed that of present-day Bahrain, one of the planet's
hottest spots, and the temperature in Bahrain 'would induce hyperthermia
in even sleeping humans.'"
These scenarios are
supported by the science. "For heat waves, our options are now between
bad or terrible," Camilo Mora, a geography professor at University of
Hawaii at Manoa, told CNN last month. Mora was the lead author of a recent study, published in the journal Nature,
showing that deadly heat days are expected to increase across the
world. Around 30 percent of the world's population today is exposed to
so-called "lethal heat" conditions for at least 20 days a year. If we
don't reduce fossil-fuel emissions, the percentage will skyrocket to 74
percent by the year 2100. Put another way, by the end of the century
nearly three-quarters of the Earth's population will face a high risk of
dying from heat exposure for more than three weeks every year.
Even the best-case scenario shows that nearly half of humanity will be exposed regularly to deadly heat by the year 2100.
This
is the worst-case scenario. Even the study's best-case scenario—a
drastic reduction in greenhouse gases across the world—shows that 48
percent of humanity will be exposed regularly to deadly heat by the year
2100. That's because even small increases in temperature can have a
devastating impact. A study published in Science Advances
in June, for instance, found that an increase of less than one degree
Fahrenheit in India between 1960 and 2009 increased the probability of
mass heat-related deaths by nearly 150 percent.
And
make no mistake: Temperatures are rising, in multiple ways. "We've got a
new normal," said Howard Frumkin, a professor at the School of Public
Health at the University of Washington. "I think all of the studies of
trends to date show that we're having more extreme heat, and we've
having higher average temperatures. Superimposed on that, we're seeing
more short-term periods of extreme heat. Those are two different trends,
and they're both moving in the wrong direction." Based on those trends,
the US Global Change Research Program predicts
"an increase of thousands to tens of thousands of premature
heat-related deaths in the summer ... each year as a result of climate
change by the end of the century." And that's along with the deaths
we've already seen: In 2015, Scientific American noted that nine out of the ten deadliest heat waves ever have occurred since 2000; together, they've killed 128,885 people.
In
other words, to understand how global warming wreaks havoc on the human
body, we don't need to be transported to some imagined dystopia.
Extreme heat isn't a doomsday scenario but an existing, deadly
phenomenon—and it's getting worse by the day. The question is whether
we'll act and adapt, thereby saving countless lives.
There
are two ways a human body can fail from heat. One is a direct heat
stroke. "Your ability to cool yourself down through sweating isn't
infinite," said Georges Benjamin, executive director of the American
Public Health Association. "At some point, your body begins to heat up
just like any other object. You go through a variety of problems. You
become dehydrated. Your skin dries out. Your various organs begin to
shut down. Your kidneys, your liver, your brain. As gross as this may
sound, you in effect, cook." (So maybe Wallace-Wells wasn't being
hyperbolic after all.)
Heat
death can also be happen due to a pre-existing condition, the fatal
effects of which were triggered by high temperature. "Heat stress
provokes huge amounts of cardiovascular strain," said Matthew Cramer of
the Institute of Exercise and Environmental Medicine. "For these people,
it's not necessarily that they've cooked, but the strain on their
cardiovascular system has led to death." This is much more common than
death by heat stroke, but is harder to quantify since death certificates
cite the explicit cause of death—"cardiac arrest," for instance, rather
than "heat-related cardiac arrest."
In both
scenarios, the body's natural ability to cool itself off through
sweating has either reached its capacity or has been compromised through
illness, injury, or medication. There are many people who have reduced
capacity for sweating, such as those who have suffered severe burns over
large parts of their bodies. Cramer,
who studies heat impacts on burned people, says 50,000 people suffer
severe burn injuries per year in America, and the World Health
Organization considers burns "a global public health problem," with the majority of severe burn cases occurring in low- and middle-income countries.
Bodies
that are battling illness or on medication may also struggle with heat
regulation. Diuretics tend to dehydrate people; anticholinergics and
antipsychotics reduce sweating and inhibit heat dissipation. An analysis
of the 2003 heat wave in France that killed 15,000 people suggested
that many of these deaths could have been avoided had people been made
aware of the side effects of their drugs. As for illnesses, "Anything
that impairs the respiratory or circulatory system will increase risk,"
said Mike McGheehin, who spent 33 years as an environmental
epidemiologist at the Centers for Disease Control and Prevention.
"Obesity, diabetes, COPD, heart disease, and renal disease." Kidney
disease, mental illness, and multiple sclerosis. The list goes on and
on.
This summer has presented many opportunities for bodies to break down from heat. Temperature records, some more than a century old, have been broken across California, Nevada, Utah, Idaho and Arizona. (Speaking of Arizona, it's been so hot there that planes can't fly.) And it's not just America. Last month, Iran nearly set the world record for highest temperature ever recorded. The May heatwave that hit India and Pakistan set new world records as well, including what the New York Timescalled
"potentially the hottest temperature ever recorded in Asia": 129.2
degrees Fahrenheit. Worldwide, 2017 is widely expected to be the second-hottest year, after 2016, since we began keeping global average temperature records in 1880.
A Pakistani resident helps a heatstroke victim at a market area during a heatwave in Karachi on June 23, 2015. RIZWAN TABASSUM / Getty Images
These
trends have public health professionals concerned about how people are
going to deal with the heat when it comes their way. "Clearly this is
one of the most important problems we're going to see from a public
health perspective," Benjamin said. "This is not a tomorrow problem.
It's a significant public health problem that we need to address today."
It's
a public health problem especially in cities, says Brian Stone, a
professor at Georgia Tech's City and Regional Planning Program. "Our
fundamental work shows that larger cities are warming at twice the rate
of the planet," he said, describing a phenomenon known as urban heat islands, where built-up areas tend to be hotter than surrounding rural areas, mainly because plants have been replaced by heat-absorbing concrete.
Global warming is making that phenomenon worse. "We're really worried
about the rate of how quickly we're starting to see cities heat up,"
Stone said.
According
to Stone's analysis, the most rapidly warming city is Louisville,
Kentucky, followed by Phoenix, Arizona, and Atlanta, Georgia. But he's
less concerned about cities like Phoenix, which already have
infrastructure to deal with brutally high temperatures, than he is about
Chicago, Buffalo, and other cities in the northern United States that
have really never had to deal with extreme heat. That is precisely why
the Chicago heat wave of 1995 that killed 759 people was so deadly.
According to the Chicago Tribune,
the city was "caught off guard," and had "a power grid that couldn't
meet demand and a lack of awareness on the perils of brutal heat."
In other words, Stone and others say, excessive death rates are not always due to just extreme temperatures, but unusual
temperatures. People are more likely to die when they are confronted
with temperatures they don't expect and thus aren't prepared for. That's
why officials in cities not experiencing heat-related extremes need to
improve emergency response systems, now. "Those people have got to start
thinking in term of, 'two years ago we had four hot days, the year
after we had eight hot days,'" Benjamin said. "Public health systems
should be put in place to respond to prolonged heat waves. Emergency
cooling centers where people can go should be built. Identify where the
people who are most socially isolated live." Absent preventative action,
heat-related deaths in New York City could quintuple by the year 2080,
according to recent research.
Some cities have already started to prepare. Stone recently completed a heat adaptation study
for Louisville that includes not only emergency management planning but
also ways the city can prevent itself from getting so hot (by improving
energy efficiency and installing green roofs, for instance). But as for
now, he said, it's rare to see a city actually adopt policies
supportive of heat management. "We do see flooding adaptation plans—New
York City has one, and New Orleans has one—but heat adaptation planning
is a very new idea, in the US and really around the world," he said. "It
takes a lot to convince a mayor that a city can actually cool itself
down. It's not intuitive."
The good news is
that humans adapt to heat, both physiologically (through
acclimatization) and socially (with air conditioning, for instance).
That will continue, according to the US Global Change Research Program,
which states with very high confidence that adaptation efforts in humans
"will reduce the projected increase in deaths from heat."
"It's a quintessential public health problem in that it impacts the most disenfranchised of our society."
But
there's a limit to this. "There's no way to adapt to heat that's more
than a certain amount," Frumkin said. "And socially, there's always
going to be people we miss, who don't have access to air conditioning."
McGeehin noted those people will likely be poor, elderly, and minority
populations. "It's a quintessential public health problem in that it
impacts the most disenfranchised of our society. Young, healthy,
middle-class people will largely be left alone," he said.
Air
conditioners also have limits, especially in cities where blackouts can
occur. "It is inevitable," Stone said, that large cities will see
blackouts during future heat waves. "The number of blackouts we see year
over year is increasing dramatically," he said. "Whether that's caused
by the heatwave or just happens during the heatwave doesn't really
matter.... The likelihood of an extensive blackout during a heatwave is
high, and getting higher as we add more devices and stressors to the
grid."
It's a "cruel irony," Frumkin said, that
as the world gets hotter, we need more air conditioning, and thus
consume more electricity. And if that electricity comes from fossil fuel
sources, it will create more global warming, which in turn will
increase the demand for air conditioning. The answer, he said, is to
"decarbonize the electric grid." But that's easier said than done,
especially when the Trump administration is devoted to increasing the
use of fossil fuels to support the country's electrical grid.
As with many other efforts to fight climate change, though, cities don't need Washington's help
to take action on heat adaptation. "Cities can manage their own heat
islands on their own, and that's where we most need to be focused,"
Stone said. But that will require convincing elected leaders that
extreme heat is big a threat as, say, rising seas—and one that can't be
addressed with something as obvious as a sea wall. That's the challenge,
says McGeehin: "Heat as a major natural disaster is mostly overlooked
in this country." It's a quiet killer, and perhaps more lethal because
of it. How Climate Change Is Already Affecting Earth Though the planet has only warmed by one-degree Celsius since the
Industrial Revolution, climate change's effect on earth has been
anything but subtle. Here are some of the most astonishing developments
over the past few years.
This story originally appeared on New Republic and is part of the Climate Desk collaboration. Links
Participants looks at a screen projecting a world map with climate
anomalies during the World Climate Change Conference 2015 (COP21).
Photograph: Stephane Mahe/Reuters
In the Paris climate treaty,
nearly every world country agreed to try and limit global warming to no
more than 2°C above pre-industrial temperatures, and preferably closer
to 1.5°C. But a new study published in Nature Climate Change notes that the agreement didn’t define when “pre-industrial” begins.
Our instrumental measurements of the Earth’s average surface
temperature begin in the late-1800s, but the Industrial Revolution began
in the mid-1700s. There’s also a theory
that human agriculture has been influencing the global climate for
thousands of years, but the mass burning of fossil fuels kicked the
human influence into high gear.
We may be at 1°C or 1.2°C warming since “pre-industrial”
We know that since the late-1800s, humans have caused global surface
temperatures to rise by about 1°C. But what about the human influence in
the centuries before that, which are technically still
“pre-industrial”? The new study used climate model simulations from 1401
to 1800, during which time we know the climate influences of natural
effects like solar and volcanic activity fairly well. They found that
depending on the starting point, global surface temperatures during that
period were 0 to 0.2°C cooler than the late-1800s.
According to the last IPCC report, to have a 50% chance of staying
below the 2°C target, when accounting for non-carbon greenhouse gases,
we have a remaining budget of about 300bn tons of carbon dioxide. But
that was for 2°C warming above late-1800 temperatures. If we add another
0.1°C of pre-industrial warming, the study authors estimated that the
budget shrinks by 60bn tons (20%), and if there was an additional 0.2°C
pre-industrial warming, the 2°C carbon budget shrinks by 40%. As one of
the study authors Michael Mann put it:
Either the Paris targets have to be revised, or alternatively, we decide that the existing targets really were meant to describe only the warming since the late 19th century.
It’s an important point if we want to measure whether we’ve succeeded
or failed in meeting the Paris climate targets. And it’s important to
know if our budget should be set at no more than 300bn tons, or more
like 200bn tons of carbon dioxide pollution.
We’re moving in the wrong direction
However, we’re not yet on track to meet the Paris climate target budget. Based on current national pledges, humans will cause around 3 to 3.5°C warming above late-1800 temperatures by 2100. However, the Paris treaty included a ratcheting mechanism
through which countries can gradually make their carbon pollution
targets more aggressive. If successful, that ratcheting could limit
global warming to 1.8°C above late-1800 temperatures, which is likely
less than 2°C above pre-industrial temperatures.
Global greenhouse gas emissions and 2100 temperatures under no action,
current pledges (INDCs), and successful ratcheting scenarios.
Illustration: Climate Interactive
To accomplish that goal, the US would have to ratchet its carbon
pollution down to 45% below 2005 levels by 2030, for example. But at the
moment, America is moving in the wrong direction, shamefully becoming the only nation announcing withdrawal
from the Paris treaty, aiming to join Nicaragua (which declined to sign
due to objections that the agreement was too weak) and Syria (which did
not participate due to a civil war) as the only non-signatory
countries. Fortunately, other countries like China and the EU are stepping up to fill the global leadership role vacated by America under the Trump administration.
Regardless, we need to cut carbon pollution ASAP
It’s also important to remember that 2°C isn’t a red line – that if
we cause 2.1°C the world will end or that at 1.9°C everything will be
fine and dandy. The 2°C target is a reasonable one for two reasons:
Above about 2°C we start to get into the realm where there’s a significant risk of major climate impacts, like widespread coral bleaching, declining food production, significant sea level rise, and up to 30% of global species at risk of extinction.
From a practical political standpoint, meeting the 2°C carbon budget is about the best we can do. Even that will require aggressive global action, with countries ratcheting down their carbon pollution targets.
But the key takeaway is that the more global warming we cause, the costlier and more damaging climate impacts will be. The faster we curb our climate pollution, the lower the risk of a climate catastrophe or especially damaging climate impacts.
We’re at the point where we need to cut carbon pollution as quickly
as feasibly possible. That’s true whether Earth has warmed 1.0 or 1.1 or
1.2°C above “pre-industrial” temperatures. However, knowing which is
the case is useful for setting concrete targets and evaluating whether
we meet them. But if we’re going to meet them, we’ll have to quickly
reverse the mistakes of the Trump administration.
Extreme El Nino events will more than double in frequency, even with
the most ambitious goals to curtail global warming, exposing large
regions to severe droughts and placing coral reefs in peril, a team of
scientists including Australians say.
In 2015, almost 200 nations
signed the Paris Climate accord, agreeing to curb greenhouse gas
emissions to prevent global temperatures warming more than 1.5-2 degrees
compared with pre-industrial times. National pledges so far point to
warming of closer to 3 degrees.
El Ninos are marked by abnormally warm temperatures in the tropical eastern Pacific that has global impacts. Photo: NASA
Even at the lower end of that range, which implies atmospheric levels
of carbon dioxide peak by about 2040-2050 before starting to decline,
big El Ninos will still become twice as common as their natural
frequency to an average of about 10 per century and continue to rise
further, according to research published in Nature Climate Change.
During
El Ninos, the eastern equatorial Pacific is unusually warm, triggering a
reversal of trade winds and a shift in rainfall patterns that often
have consequences - such as droughts in Australia and the Horn
of Africa, heavy rain in South America - well beyond the region. During
extreme events, most recently in 2015-16, impacts can intensify.
"[During] big blockbuster El Ninos, if they happen more frequently,
we can expect more damage and loss of life because of that," said
Michael McPhadden, a senior scientist at the US National Oceanic and
Atmospheric Administration and an author of the report that analysed 13
climate models.
"The number [of El Nino] might not necessarily increase but the stronger ones will get stronger," he said.
Cai Wenju, a principal research scientist at the CSIRO and one of the
paper's lead authors, said the frequency of extreme El Ninos is
beginning to emerge from the natural variability. There have been four
such events since 1950 compared with one in the previous half century.
"To our surprise, if you stabilise GMT at 1.5 degrees, the extreme El
Ninos continue to rise," Dr Cai said. "After that, the frequency of
extremes rises another 40 per cent" to as often as one in every seven
years before finally stabilising.
Aiming for that 1.5-degree
warming cap is still worthwhile not least because the frequency of
severe El Ninos will increase even faster if temperatures climb higher,
Dr Cai said.
A young Somali girl displaced by drought wears mock spectacles cut from
an antibiotics medicine box at a relief camp near the capital,
Mogadishu, in March 2017. Photo: AP
Moreover, the flipside pattern, extreme La Ninas, do not increase in
frequency at 1.5 degrees, the researchers found, but do so at higher
warming levels. Complex circulation patterns mean the threshold for
extreme El Nino events is more easily crossed with on-going warming than
La Ninas.
"El Ninos are more sensitive to greenhouse forcing than
La Nina but you'll reach a point where radiative forcing from excess
greenhouse gas where both El Ninos and La Ninas will experience more
extreme events," Dr McPhadden said.
Coral reefs, already struggling as water temperatures rise, will face severe threats during heat spikes, scientists say. Photo: WWF-Aus/BioPixel
Heat goes on
Apart from the regional impacts, El Ninos typically drive surface
temperatures higher as the Pacific absorbs less of the excess heat being
collected in the atmosphere from the additional greenhouse gases.
The
past three years – 2014, 2015, and 2016, each broke annual records as
the Pacific flirted and then fell into a full-blown El Nino. Even
2017 is likely to be among the hottest, with the first six months the
second warmest on record, trailing only last year, NOAA said last week. (See NOAA chart below.)
Impacts
La Ninas have their own negative impacts, including above-average
numbers of cyclones in northern Australia, but the global effects of El
Ninos tend to be worse, Dr Cai said. That's even taking into account big
floods in China in 1998 during a record strong La Nina.
"El Ninos
tend to have huge areas of drought and the impacts may be more
long-lasting than flood," Dr Cai said. With droughts, farmers may miss
out on several planting seasons and natural eco-systems can take longer
to recover compared with floods.
El Nino years have also seen
severe coral bleaching and mortality as the corals respond to excess
heat by expelling the algae that provide them with the bulk of their
energy. As much as half of the Great Barrier Reef corals have died
during the past two summers.
The rising background temperatures
from climate change mean the heat spikes during El Ninos can be expected
to make coral bleaching more common in the future.
"You can envisage these kinds of impacts with the more frequent [extreme El Nino] events in the future," Dr McPhadden said.
The
recent bleaching "was shocking how extensive it was, and how it
affected so severely areas that had not been affected before", he said.
"Can they adapt? If not, there are some hard times ahead."
The Greenland ice sheet covers an area about seven times the size of the UK. Kate Stephens
Scientists are "very worried" that
the melting of the Greenland ice sheet could accelerate and raise sea
levels more than expected.
They say warmer conditions are encouraging algae to grow and darken the surface.
Dark ice absorbs more solar radiation than clean white ice so warms up and melts more rapidly.
Currently the Greenland ice sheet is adding up to 1mm a year to the rise in the global average level of the oceans.
It
is the largest mass of ice in the northern hemisphere covering an area
about seven times the size of the United Kingdom and reaching up to 3km
(2 miles) in thickness.
This means that the average sea level would rise around the world by about seven metres, more than 20ft, if it all melted.
That
is why Greenland, though remote, is a focus of research which has
direct relevance to major coastal cities as far apart as Miami, London
and Shanghai and low-lying areas in Bangladesh and parts of Britain.
Algae
were first observed on the Greenland ice sheet more than a century ago
but until recently its potential impact was ignored. Only in the last
few years have researchers have started to explore how the
microscopically small plants could affect future melting.
A
five-year UK research project known as Black and Bloom is under way to
investigate the different species of algae and how they might spread,
and then to use this knowledge to improve computer projections of future
sea level rise.
The possibility of biologically inspired melting
was not included in the estimates for sea level rise published by the
UN's climate panel, the IPCC, in its latest report in 2013.
Scientists are investigating the different species of algae and how they might spread. Marian Yallop
That study said the worst-case scenario was a rise of 98cm by the end of the century.
One
concern now is that rising temperatures will allow algae to flourish
not only on the slopes of the narrow margins of the ice-sheet but also
on the flat areas in the far larger interior where melting could happen
on a much bigger scale.
We joined the latest phase of research in
which scientists set up camp on the ice-sheet to gather accurate
measurements of the "albedo" or the amount of solar radiation reflected
by the surface.
White snow reflects up to 90% of solar radiation
while dark patches of algae will only reflect about 35% or even as
little as 1% in the blackest spots.
When we flew by helicopter
onto the ice sheet, the rolling landscape seemed surprisingly grey - my
first impression was that it looked dirty.
Much of the surface
was covered with what looked like patches of soot and it was pockmarked
with countless holes at the bottom of which were pitch-black layers of a
mix of algae, bacteria and minerals known as cryoconite.
Prof Martyn Tranter of Bristol University, who is leading the project, told me:
"People are very worried about the possibility that the ice sheet might be melting faster and faster in the future.
"We
suspect that in a warming climate these dark algae will grow over
larger and larger parts of the Greenland ice sheet and it might well be
that they will cause more melting and an acceleration of sea level rise.
"Our project is trying to understand just how much melting might occur."
Over
the last 20 years, Greenland has been losing more ice than it gains
through snowfall in winter - a change in a natural balance that normally
keeps the ice-sheet stable.
Biological darkening has not been built into scientists' climate projections. Kate Stephens
And one of the project scientists, Dr Andrew Tedstone, a glaciologist
and also of Bristol University, said that over much of the same period,
images from the MODIS satellite showed a darkening trend with the years
of greatest dark producing most meltwater.
He said: "We still
don't think we've reached a point where we've seen the maximum darkness
that we're going to see in this area so the fieldwork we're doing is to
try to find out in a warming climate 'do we think the area is going to
get any darker than we've already seen in the last 15 years?'"
Earlier
research had found that the ice sheet is covered with a range of
contaminants carried on the winds including dust and soot from as far
away as Canadian prairie fires and the industrial heartlands of China,
America and Europe.
But studies over the past five years have
shown that the majority of the dark material may be biological with
different kinds of algae turning the ice black, brown, green and even
mauve.
"This is a living landscape," according to Dr Joe Cook, a glacial microbiologist at Sheffield University.
"This
is an extremely difficult place for anything to live but, as we look
around us, all this darkness we can see on the ice surface is living -
algae, microbes, living and reproducing in the ice sheet and changing
its colour."
Ice retreat does not have to be total to have a damaging impact. Kate Stephens
"We know they're very widespread and we know that they're very dark
and we know that that's accelerating melt but that's not something
that's built into any of our climate projections - and that's something
that needs to change."
The final phase of the Black and Bloom
project involves weaving the new factor of biological darkening into
climate models to come up with revised estimates for future sea level
rise.
And, as Dr Cook explained, the retreat of the Greenland ice
sheet does not need to be total to have a widespread and damaging
impact.
"When we say the ice sheet is melting faster, no one
saying it's all going to melt in next decade or the next 100 years or
even the next 1,000 years but it doesn't all have to melt for more
people to be in danger - only a small amount has to melt to threaten
millions in coastal communities around world."
Meanwhile,
another factor that may be driving the melting has been identified by an
Austrian member of the team, Stefan Hofer, a PhD student at Bristol.
In a paper recently published in Science Advances,
he analysed satellite imagery and found that over the past 20 years
there has been a 15% decrease in cloud cover over Greenland in the
summer months.
"It was definitely a 'wow' moment," he told me.
Although
temperature is an obvious driver of melting, the paper estimated that
two-thirds of additional melting, above the long-term average, was
attributable to clearer skies.
What is not known is how this
might affect the algae. Their darker pigments are believed to be a
protection from ultra violet light - so more sunshine might encourage
that process of darkening or prove to be damaging to them.
The
Black and Bloom project, funded by the Natural Environment Research
Council (Nerc), aims to publish its new projections for sea level rise
in two years' time.
