A Californian solar and battery storage power purchase agreement is
plumbing new lows for the cost of electricity from solar – a US-dollar
price of 1.99c/kWh for 400MW of PV and 1.3c/kWh for stored solar power
from a co-located 400MW/800MWh battery storage system.
The record
setting deal, struck by a team at the Los Angeles Department of Water
and Power (LADWP) with renewables developer 8minute, seeks to lock-in a
two-stage, 25-year contract to serve 7 per cent of L.A.’s electricity
demand from the massive solar and battery project.
The project,
called the Eland Solar and Storage Center, would be built in two 200MW
stages in Kern County north of Los Angeles, with an option to add a
further 50MW/200 MWh of energy storage for 0.665 cents per kWh more.
The
project aims not only to help power L.A. during the day with dirt-cheap
solar power but to use the stored battery power in the evening peak
period to ease the effect of fossil fuel “ramping” as the solar leaves
the system.
And while the project’s size is impressive –
particularly the size of the battery system, which would be twice the
size of the world’s current biggest big battery, Australia’s own
Hornsdale Power Reserve – it has been the prices quoted for the PPA that
have really caught the market’s attention.
As PV Magazine’s John Weaver noted,
the current world record solar power price was set in Mexico at
1.97¢/kWh as part of a batch of projects averaging just over 2¢/kWh. A
lower bid submitted in Saudi Arabia at 1.79¢/kWh was not ultimately
signed.
“This is the lowest solar-photovoltaic price in the United
States, and it is the largest and lowest-cost solar and high-capacity
battery-storage project in the U.S., and we believe in the world today,”
said the LADWP’s manager for strategic initiatives, said James Barner.
“So this is, I believe, truly revolutionary in the industry.”
Barner
has also noted that the project has been able to make “full use” of a
“substantial” federal solar investment tax credit, which amounted to
around 30 per cent “basically knocked off the capital cost of the
project.”
According to reports, Barner told a June briefing on the
project that net peak load in the evening would be offset by the Eland
facility, to keep gas powered generation “not running at the full
amount.”
“The battery can be dispatched differently, depending on
the system need,” he said. “So you could run that four-hour battery over
16 hours at one-fourth of the output so that you can vary it over time.
It’s not just fixed over four hours.
“The battery is able to take
a portion of (the) solar from that facility …and then store it into the
battery so that the facility can provide a constant output to the grid.
It can turn this solar facility, which is not typically dispatchable,
into a dispatchable type of facility.”
According to data from the U.S. Energy Information Agency, and quoted in Forbes,
a natural-gas plant opening at the same time as the Eland facility
would produce power at more than twice the price, or 4-4.3¢/kWh.
Presuming
the power off-take contract is approved, the Eland project is expected
start construction in 2022, with the first production expected in the
first half of 2023, and a guaranteed commercial operation date of the
last day of that year, PV Magazine reported.
Environmental activists demonstrate during a Extinction Rebellion protest April 17 in London. (Henry Nicholls/Reuters)
The consulting firm Moody’s Analytics says climate
change could inflict $69 trillion in damage on the global economy by the
year 2100, assuming that warming hits the two-degree Celsius threshold
widely seen as the limit to stem its most dire effects.
Moody’s says in a new climate change report that
warming of 1.5 degrees Celsius, or 2.7 degrees Fahrenheit, increasingly
seen by scientists as a climate-stabilizing limit, would still cause
$54 trillion in damages by the end of the century.
The
firm warns that passing the two-degree threshold “could hit tipping
points for even larger and irreversible warming feedback loops such as
permanent summer ice melt in the Arctic Ocean.”
The
new report predicts that rising temperatures will “universally hurt
worker health and productivity” and that more frequent extreme weather
events “will increasingly disrupt and damage critical infrastructure and
property.”
Moody’s Analytics chief economist
Mark Zandi said that the report was “the first stab at trying to
quantify what the macroeconomic consequences might be” of climate
change, written in response to European commercial banks and central
banks.
Climate change, Zandi said, is “not a
cliff event. It’s not a shock to the economy. It’s more like a
corrosive.” But, he added, it’s one that is “getting weightier with each
passing year.”
Moody’s Investors Service, a
major credit ratings agency, has already said that it wants to take
climate into account when weighing the financial health of companies and
municipalities.
The new report highlights the harm done to human health, labor productivity, crop yields and tourism.
It
says that “water- and vector-borne diseases such as malaria and dengue
fever will likely be the largest direct effect of changes in human
health and the associated productivity loss.”
The
report also says that rising temperatures will allow mosquitoes, ticks
and fleas to move to new areas, resulting in more sick days. It would
also raise public and private spending on health care.
Labor productivity will take a hit, especially among outdoor workers, including those working in agriculture.
The
hardest-hit economies will be some of the fastest-growing ones —
Brazil, Russia, India, China and South Africa, the report says.
The
Moody’s Analytics report also forecasts lower oil and natural gas
demand, dealing a blow to oil-exporting countries, especially in the
Middle East. It forecasts that Saudi GDP will drop more than 10 percent
by 2048; the kingdom would be the country harmed the most by climate
change, hurting government revenue, Moody’s says.
Although
Saudi Arabia has suffered drops in GDP when highly cyclical oil prices
sink, Moody’s says that the kingdom would suffer more lasting harm as a
result of climate change.
Of the 12 largest
economies, India will be the worst hit, the report says, with GDP
growing 2.5 percentage points more slowly than it would without the
effects of climate change. The country’s service industry will be hit by
heat stress, agricultural productivity will fall, and health-care costs
will climb.
The firm carried out different
scenarios using an international study by the World Bank, taking
different locations into account and weighing different economic
sectors. It said that rising sea levels would damage coastal real
estate, wiping out rental incomes in some areas and thus cutting
consumer spending.
But the scenarios only go
through 2048. The Moody’s report says “the distress compounds over time
and is far more severe in the second half of the century.”
“That’s
why it is so hard to get people focused on this issue and get a
comprehensive policy response,” Zandi said. “Business is focused on the
next year, or five years out.”
He added: “Most
of the models go out 30 years, but, really, the damage to the economy is
in the next half-century, and we haven’t developed the tools to look
out that far.”
Other businesses are peering ahead on climate change, too.
Chubb,
one of the biggest insurance firms in the United States, on Monday said
it would no longer sell insurance to new coal-fired power plants or
sell new policies to companies that derive more than 30 percent of their
revenue from the mining of coal used in power plants.
Although
more than a dozen leading insurance companies in Europe have already
cut off insurance for coal companies, U.S. firms have resisting pressure
to take climate change into account.
Chubb’s
step was just an initial one. “A major U.S. insurer like Chubb
restricting insurance for coal projects and companies is a
game-changer,” said Ross Hammond, a senior strategist for the Insure Our
Future campaign, which has tried to pressure insurance companies to
pull out of the coal market. But Hammond said that the company still
needs to stop insuring new coal mines and the oil sands, or tar sands,
in northern Alberta.
Lindsey Allen, executive
director of Rainforest Action Network, said that “new coal projects
cannot be built without insurance, and Chubb just dealt a blow to the
dozens of companies that are still betting on the expansion of coal
globally.”
Separately, the chief economist of
Equinor, the Norwegian oil company previously known as Statoil, has
written a report that looks at three scenarios for climate change and
its impact on global economies, especially on energy.
Only
one of those, the report said, would lead to a sustainable path, but
that path comes with enormous challenges. To reach that set of targets
by 2050, “almost all use of coal must be eradicated,” oil demand would
need to be halved, and natural gas demand trimmed by more than
10 percent. Renewables as well as carbon capture and storage or
utilization would have to increase sharply, helped by continuing
advances in technology.
“In
order to hit 1.5 degrees Celsius, the model to get there is enormously
challenging,” said Eirik Waerness, senior vice president and chief
economist of Equinor. He said more than half of new cars would have to
be electric vehicles by 2030. Electricity demand will double, yet wind
and solar would equal the entire current electricity output, a leap from
current levels.
The threshold of 1.5 degree Celsius is the target set by most climate scientists for avoiding dire climate change.
Waerness
also said that the company currently assumes a carbon price of $55 a
ton when considering whether to finance new energy projects. As a
result, Equinor has been investing more in projects such as offshore
wind, where it can also tap into its experience with offshore platforms
and technology.
To scientists in Antarctica, President Trump is weirder than a sea pig.
On Tuesday, Trump tweeted a quote from Patrick Moore, a well-known climate denier who claims to have been a co-founder of Greenpeace. (He wasn’t, and Greenpeace has disavowed him as a “paid lobbyist.”)
“The whole climate crisis is not only Fake News, it’s Fake Science,” Trump quoted Moore as saying on an episode of Fox & Friends.
A day later, I asked Rob Larter, the chief scientist aboard the Nathaniel B. Palmer, where we have spent the past six weeks in Antarctica doing Real Science, what he thought of Trump’s tweet. Larter can talk about the movement of the Earth’s continents 500 million years ago as breezily as other men talk about off-season baseball trades. And of course out here in Antarctica, Larter had been far too busy during the past 24 hours actually contributing to the sum of human knowledge to pay attention to tweets from the conspiracy theorist in the Oval Office.
I showed Trump’s tweet to Larter on my iPhone. As he read it, he smiled slightly and shook his head. “It’s crazy talk,” said Larter, who is British. “Do any Americans really believe that stuff?”
Patrick Moore, co-founder of Greenpeace: “The whole climate crisis is not only Fake News, it’s Fake Science. There is no climate crisis, there’s weather and climate all around the world, and in fact carbon dioxide is the main building block of all life.” @foxandfriends Wow!
The 55 scientists and crew members from around the world who are aboard the Palmer with me have been living in a Trump-free paradise for weeks. We get very little news, as we are bandwidth-starved and have only intermittent connection to the outside world via internet and satellite phone.
But I’ll admit Trump’s tweet woke me up to a curious point: During this entire six-week cruise, I have lived in close quarters with my shipmates. I know what kind of cake was served at their kid’s birthday party and their views about the afterlife and why they believe that physicists who research the existence of other dimensions are likely to be crackpots. But there has been very little talk of climate politics or climate policy. The subject of Trump’s re-election comes up, and the Brits talk a lot about the disaster known as Brexit. There is much debate about internal politics at various universities, and within the National Science Foundation and the UK’s National Environment Research Council, both of which are funding this trip, which is part of a five-year-long collaboration to better understand the risks of collapse of Thwaites glacier in West Antarctica.
But as far as I can tell, the words “Green New Deal” have not been uttered on the ship by a scientist, nor have the words “carbon footprint” or “Paris climate accords.” I overheard one scientist engaged in a not-particularly-well-informed debate with the captain about the pros and cons of wind power, but that has been about it.
It’s not entirely surprising. “You don’t bring up climate politics because you have to live with people on the ship in very close quarters for seven weeks,” says Lars Boehme, an oceanographer from University of St. Andrews who has successfully tagged 11 seals on the trip. “It’s divisive.” Bastien Queste, a researcher from the University of East Anglia in the UK, has a different view: “Why talk about climate politics? We all have similar views on the ship. We all are big supporters of clean energy. We all know we have to get off fossil fuels. What is there to discuss?”
But even off the ship, the reluctance to get involved in politics persists. So far as I can tell, none of the scientists on this trip are engaged in climate-related political activism in their daily lives. Few are even comfortable talking about it. Several started squirming as soon as I brought it up. Two of the youngest researchers on the trip, one from the U.S. and one from Sweden, told me they have actually quit climate activism in recent years simply because they have no time.
Building a career in science is a brutally competitive endeavor, sucking up all your time and energy. But for many, the real problem with climate activism is that it requires dealing with the media. And if there is one thing that spooks climate scientists more than collapsing glaciers, it’s a person with a microphone. It’s not hard to see why. Scientists deal with facts, not characters or emotions.
They often see journalists as ignorant about science and all too eager to transform scientific debates into a new front in the culture wars. And they are not always wrong about that. “To be good at communicating about science, you have to spend a lot of time at it,” explains Queste. “If you try to analyze data and communicate with the public, it’s nearly impossible to find the time to do both very well.”
There is also the fear that if they are outspoken, they might be seen as too “political” and not do as well with research grants or other funding. That’s not a trivial question these days, when science budgets are slashed and tenured positions at universities are increasingly difficult to secure. It’s much easier just to keep your head down and do the work. “I am paid to do science,” one U.S. scientist on the trip told me. “So I do science.”
Others worry about offending family and friends by speaking out too bluntly. One scientist talked about a friend who published a paper on climate change in Nature, a top scientific journal, then received threats online. “This is a dangerous time to be a climate scientist,” the scientist said. And if the reaction of researchers on the Palmer is any indication, American scientists feel that danger more viscerally than most (and, not surprisingly, were more reluctant to talk on the record for this dispatch).
But to some U.S. scientists, it’s also a dangerous time to keep silent. From the Palmer, I emailed Andrea Dutton, a highly-regarded geologist at the University of Florida, about her reaction to Trump’s tweet. “This is no longer a matter of simple misrepresentation,” she wrote. “It is dangerous and reckless for our leaders to mislead the American people about the impacts of global warming. As a scientist, and perhaps more importantly, as a citizen of the U.S., I do feel that I have a moral obligation to speak out against misinformation. The American people deserve the truth about their future.”
One thing that has become very clear on this journey to Antarctica is that climate science is risky in all kinds of ways — including risks to life and limb. On the ship, instruments are dropped into the sea in the middle of the night while the deck of the ship pitches wildly in rough seas; winches spin with cables attached to 700-pound coring devices; marine technicians launch Zodiac boats in rough seas. On the Palmer, science goes on 24/7, no matter how bad the weather, no matter how exhausted you are.
Queste has been in the middle of most of it. When I sat down with him in the mess hall yesterday, he looked more tired than most. I asked him if he had seen Trump’s tweet. He hadn’t. So I showed it to him. “I can’t handle this much crap,” he moaned, his face drained from long hours in the lab. “It depresses me. Such blatant pandering and shit-stirring.”
A few minutes later, I showed Trump’s tweet to Lars Boehme, who seized onto a line in the tweet about carbon dioxide being “one of the main building blocks of life.” It’s a well-worn talking point for climate deniers. “You like carbon dioxide so much?” Boehme mused. “Try putting a plastic bag over your head and see how that works out.”
But perhaps the best response to Trump’s tweet came from Anna Wåhlin, a professor of physical oceanography at the University of Gothenburg and leader of the team that sent the Hugin, a semi-intelligent underwater research device, 1,500 feet beneath Thwaites glacier.
It was one of the most remarkable scientific achievements of the trip, and the data the Hugin collected has already helped scientists understand how ocean currents circulate in West Antarctica, pushing warm water beneath Thwaites and melting it from below. This is what science is supposed to do — go underneath our everyday world and make the unknown known.
Late Wednesday night, the lab on the Palmer boomed with the sound of the ship’s hull busting through thick sea ice. I asked Wåhlin if she’d seen Trump’s tweet. “No, I have not,” she replied.
She read it on my iPhone, then looked at me with something beyond anger or disgust. “I’m sorry,” she said.
Researchers identified 0.9 billion hectares of land that is available to be reforested
That could buy us a 20 year pause in climate warming
Coastal ecosystems are capable of storing carbon up to 40 times faster than forests and should also be considered, expert says
Planting trees to reduce the amount of carbon dioxide in the
atmosphere seems like a no-brainer in the fight against climate change.
But until recently it's not been clearhow
much land we'd need to make a tangible difference to warming, and
whether we'd need to reclaim farm and residential land to do it.
Now new research published today in Science estimates there's enough suitable unusedland on the globe for reforestation to store around 205 gigatonnes of carbon.
That's
enough to buy us about 20 years in the fight against climate change,
according to researcher Jean-Francois Bastin from the Institute of
Integrative Biology in Zurich.
"This would definitely help to keep us at that maximum of 1.5 degrees by 2050," Dr Bastin said.
The researchers started by modelling the amount of tree cover
the earth could sustain under current environmental conditions, if
there were no humans on the planet.
They considered local climate factors like rainfall and temperature in their modelling.
Then they worked backwards, subtracting existing tree cover, urban environments and agricultural land.
They
were left with 0.9 billion hectares of degraded land, which could be
returned to canopy cover ranging from open savannah to dense forest.
The
land they identified had been affected by things like logging,
slash-and-burn fire regimes, intensive ongoing burning and clearing for
grazing.
Other technological methods for combatting climate
change, such as injecting sulphate aerosols into the stratosphere, have
been proposed but most carry significant risks or are yet to be proven
at scale.
The beauty of reforestation, according to Dr Bastin, is that it's win-win.
"When
you think about tree restoration, it's not only about fighting climate
change it's also about maintaining ecosystems," he said.
"The forests of the world protect 80 per cent of the biodiversity that exists on land."
Reforestation needs to happen before 'tipping point'
The
researchers also modelled the effect that climate change will have on
how much of the earth's surface will be able to support trees in future.
Their findings suggest that reforestation needs to happen soon if it is to be effective.
Under current forecasts, they project that global tree canopy cover will shrink by up to 223 million hectares by 2050.
The impacts will be most significant at the tropics, according to Dr Bastin.
"The tropics will be under a lot more climatic stress. There will be more severe droughts," he said.
"Forests are a little bit resilient. But at some point we are afraid
that it might shift, hit a tipping point and we are going to lose a
lot."
An argument often espoused by climate-change sceptics is that more carbon in the atmosphere will equal more plant growth.
But
David Ellsworth, an expert in the response of forests to climate change
from the University of Western Sydney, said that wasn't the case.
Instead, tree growth is limited by a range of factors, including water availability and how nutrient-rich the soil is.
"What we know is that phosphorous is very limiting [in places like Australia]," Professor Ellsworth said.
He
has conducted experiments where plants are exposed to the levels of CO2
predicted in the future, and observed no significant changes in growth
rate.
While today's research points to exciting possibilities, he
warned that the amount of CO2 that could be absorbed should be treated
with some caution.
He said that by not factoring in soil nutrients
or the full range of carbon densities of different vegetation types,
there was room for error.
Most potential reforestation land in Australia and five other countries
More
than half of the land available for what the researchers call "tree
restoration potential" was identified in just six countries.
Australia ranked fourth on the list, behind Russia, the United States and Canada, and was followed by Brazil and China.
Twenty million trees are expected to be planted in Australia by 2020 under a federal government program.
But critics say any reforestation efforts in Australia are being undermined by land clearing.
Deforestation in Australia in recent years has spiked, drawing comparisons with tree-clearing hotspots like the Amazon rainforest in Brazil.
In
2017 around 1,000 football fields were being cleared each day in
Queensland, and more than a million hectares were cleared in that state
between 2012 and 2016.
The Nature Conservation Council (NCC) claims around onefootballfield of bushland was cleared in New South Wales every 10 minutes, in 2017-18.
"We are in an extinction and climate emergency. We must stop
destroying wildlife habitat if we are going to stop more species
disappearing," NCC CEO Kate Smolski said in a statement last week.
A million species worldwide are now under threat of extinction, according to a UN-backed report published in May this year.
In Australia, 121 species are listed as critically endangered by the IUCN, with 41 species having gone extinct.
A further 239 are endangered.
Numerous
critically endangered and endangered species, including Leadbeater's
possum, swift parrots and bettong could benefit from forest restoration
in Australia.
'Armpits of the ocean' can store carbon 40 times faster
But forests aren't the only ecosystems that can help fight climate change.
While trees are able to draw down carbon dioxide from the atmosphere and store it for the duration of their lives, blue carbon ecosystems can do it up to 40 times faster, and can potentially lock away carbon for 1,000 years or more.
Blue carbon is the term referring to stored carbon in coastal ecosystems like mangroves, seagrass and salt marshes.
But
according to Peter Macreadie from the Blue Carbon Lab at Deakin
University, these systems which he calls the "armpits of the ocean" have
an image problem.
"That's a big, big problem," Dr Macreadie said.
"I'm working on a program in the Maldives where they're ripping out
seagrass because people don't like the look of the dark patches in the
water."
Getting public support to conserve and restore habitats that
might be muddy and smelly and home to mosquitoes and sand flies is a
difficult ask.
But in terms of a carbon sequestration investment,
blue carbon is better value for money than tree planting, according to
Dr Macreadie.
"If you're a carbon offset provider you're going to
think, 'I can store the same amount of carbon in a fortieth of the land
area'," he said.
Like planting trees, restoring coastal ecosystems
has other benefits as well like boosting fish stocks and buffering
coastlines from storm surges and sea-level rise.
While we focus on decarbonising our economies, restoring natural ecosystems may buy us precious time, according to Dr Bastin.
"We cannot be too picky. We need to use every good idea we can develop to fight climate change."
Researchers say an area the size of
the US is available for planting trees around the world, and this could
have a dramatic impact on climate change.
The study shows that the space available for trees is far greater than previously thought, and would reduce CO2 in the atmosphere by 25%.
The authors say that this is the most effective climate change solution available to the world right now.
But other researchers say the new study is "too good to be true".
The ability of trees to soak up carbon dioxide has long made them a valuable weapon in the fight against rising temperatures.
The
Intergovernmental Panel on Climate Change (IPCC) said that if the world
wanted to limit the rise to 1.5C by 2050, an extra 1bn hectares (2.4bn
acres) of trees would be needed.
The problem has been that accurate estimates of just how many trees the world can support have been hard to come by.
This
new report aims to show not just how many trees can be grown, but where
they could be planted and how much of an impact they would have on
carbon emissions.
A map showing only the potential for restoring forests and excluding desert, agricultural and urban areas. Crowther
The scientists from ETH-Zurich in Switzerland used a method called
photo-interpretation to examine a global dataset of observations
covering 78,000 forests.
Using the mapping software of the Google
Earth engine they were able to develop a predictive model to map the
global potential for tree cover.
They found that excluding
existing trees, farmland and urban areas, the world could support an
extra 0.9bn hectares (2.22bn acres) of tree cover.
Once these
trees matured they could pull down around 200 gigatonnes of carbon
dioxide, some two-thirds of extra carbon from human activities put into
the atmosphere since the industrial revolution.
This is a quarter of the overall amount of CO2 in the air.
"Our
study shows clearly that forest restoration is the best climate change
solution available today and it provides hard evidence to justify
investment," said Prof Tom Crowther, the senior author on the study.
"If we act now, this could cut carbon dioxide in the atmosphere by up to 25%, to levels last seen almost a century ago."
The
researchers identify six countries where the bulk of the forest
restoration could occur: Russia (151m hectares), US (103m), Canada
(78m), Australia (58m), Brazil (50m) and China (40m).
Crowther Lab
But they say speed is of the essence because as the world continues
to warm then the potential area for planting trees in the tropics would
be reduced.
"It will take decades for new forests to mature and achieve this potential," said Prof Crowther.
"It
is vitally important that we protect the forests that exist today,
pursue other climate solutions, and continue to phase out fossil fuels
from our economies."
The new study has been welcomed by Christiana
Figueres, former UN climate chief, who was instrumental in delivering
the Paris climate agreement in 2015.
"Finally an authoritative
assessment of how much land we can and should cover with trees without
impinging on food production or living areas," she said in a statement.
"A hugely important blueprint for governments and private sector."
What do the critics say?
However not everyone was as effusive about the new study.
Several
researchers expressed reservations, taking issue with the idea that
planting trees was the best climate solution available to the world
right now.
"Restoration of trees may be 'among the most effective
strategies', but it is very far indeed from 'the best climate change
solution available,' and a long way behind reducing fossil fuel
emissions to net zero," said Prof Myles Allen from the University of
Oxford.
Planting trees is important say some scientists but cutting emissions is paramount. Getty Images
Others are critical of the estimates of carbon that could be stored if these trees were planted.
"The
estimate that 900 million hectares restoration can store an addition
205 billion tonnes of carbon is too high and not supported by either
previous studies or climate models," said Prof Simon Lewis from
University College London.
"Planting trees to soak up two-thirds
of the entire anthropogenic carbon burden to date sounds too good to be
true. Probably because it is," said Prof Martin Lukac from the
University of Reading.
"This far, humans have enhanced forest
cover on a large scale only by shrinking their population size (Russia),
increasing productivity of industrial agriculture (the West) or by
direct order of an autocratic government (China). None of these
activities look remotely feasible or sustainable at global scale."
The study has been published in the journal Science.
Research shows a trillion trees could be planted to capture huge amount of carbon dioxide
Redwood trees in Guerneville, California.
Photograph: Gabrielle Lurie/The Guardian
Planting billions of trees across the world is by far the biggest and
cheapest way to tackle the climate crisis, according to scientists, who
have made the first calculation of how many more trees could be planted
without encroaching on crop land or urban areas.
As trees grow, they absorb and store the carbon dioxide emissions
that are driving global heating. New research estimates that a worldwide
planting programme could remove two-thirds of all the emissions that
have been pumped into the atmosphere by human activities, a figure the
scientists describe as “mind-blowing”.
The analysis found there are 1.7bn hectares of treeless land on which
1.2tn native tree saplings would naturally grow. That area is about 11%
of all land and equivalent to the size of the US and China combined.
Tropical areas could have 100% tree cover, while others would be more
sparsely covered, meaning that on average about half the area would be
under tree canopy.
The scientists specifically excluded all fields used to grow crops
and urban areas from their analysis. But they did include grazing land,
on which the researchers say a few trees can also benefit sheep and
cattle.
“This new quantitative evaluation shows [forest] restoration isn’t
just one of our climate change solutions, it is overwhelmingly the top
one,” said Prof Tom Crowther at the Swiss university ETH Zürich, who led
the research. “What blows my mind is the scale. I thought restoration
would be in the top 10, but it is overwhelmingly more powerful than all
of the other climate change solutions proposed.”
Crowther emphasised that it remains vital to reverse the current trends of rising greenhouse gas emissions from fossil fuel burning and forest destruction,
and bring them down to zero. He said this is needed to stop the climate
crisis becoming even worse and because the forest restoration envisaged
would take 50-100 years to have its full effect of removing 200bn
tonnes of carbon.
Guardian graphic. Source: Bastin et al, Science, 2019
But tree planting is “a climate change solution that doesn’t require
President Trump to immediately start believing in climate change, or
scientists to come up with technological solutions to draw carbon
dioxide out of the atmosphere”, Crowther said. “It is available now, it
is the cheapest one possible and every one of us can get involved.”
Individuals could make a tangible impact by growing trees themselves,
donating to forest restoration organisations and avoiding irresponsible
companies, he added.
Other scientists agree that carbon will need to be removed from the atmosphere to avoid catastrophic climate impacts and have warned that technological solutions will not work on the vast scale needed.
Jean-François Bastin, also at ETH Zürich, said action was urgently
required: “Governments must now factor [tree restoration] into their
national strategies.”
Christiana Figueres, former UN climate chief and founder of the Global Optimism
group, said: “Finally we have an authoritative assessment of how much
land we can and should cover with trees without impinging on food
production or living areas. This is hugely important blueprint for
governments and private sector.”
René Castro, assistant-director general at the UN Food and
Agriculture Organisation, said: “We now have definitive evidence of the
potential land area for re-growing forests, where they could exist and
how much carbon they could store.”
The study, published in the journal Science,
determines the potential for tree planting but does not address how a
global tree planting programme would be paid for and delivered.
Crowther said: “The most effective projects are doing restoration for
30 US cents a tree. That means we could restore the 1tn trees for
$300bn [£240bn], though obviously that means immense efficiency and
effectiveness. But it is by far the cheapest solution that has ever been
proposed.” He said financial incentives to land owners for tree
planting are the only way he sees it happening, but he thinks $300bn
would be within reach of a coalition of billionaire philanthropists and
the public.
Effective tree-planting could take place across the world, Crowther
said: “The potential is literally everywhere – the entire globe. In
terms of carbon capture, you get by far your biggest bang for your buck
in the tropics [where canopy cover is 100%] but every one of us can get
involved.” The world’s six biggest nations, Russia, Canada, China, the
US, Brazil and Australia, contain half the potential restoration sites.
Tree planting initiatives already exist, including the Bonn Challenge,
backed by 48 nations, aimed at restoring 350m hectares of forest by
2030. But the study shows that many of these countries have committed to
restore less than half the area that could support new forests. “This
is a new opportunity for those countries to get it right,” said
Crowther. “Personally, Brazil would be my dream hotspot to get it right –
that would be spectacular.”
The research is based on the measurement of the tree cover by
hundreds of people in 80,000 high-resolution satellite images from
Google Earth. Artificial intelligence computing then combined this data
with 10 key soil, topography and climate factors to create a global map
of where trees could grow.
This showed that about two-thirds of all land – 8.7bn ha – could
support forest, and that 5.5bn ha already has trees. Of the 3.2bn ha of
treeless land, 1.5bn ha is used for growing food, leaving 1.7bn of
potential forest land in areas that were previously degraded or sparsely
vegetated.
“This research is excellent,” said Joseph Poore, an environmental
researcher at the Queen’s College, University of Oxford. “It presents an
ambitious but essential vision for climate and biodiversity.” But he
said many of the reforestation areas identified are currently grazed by
livestock including, for example, large parts of Ireland.
“Without freeing up the billions of hectares we use to produce meat
and milk, this ambition is not realisable,” he said. Crowther said his
work predicted just two to three trees per field for most pasture:
“Restoring trees at [low] density is not mutually exclusive with
grazing. In fact many studies suggest sheep and cattle do better if
there are a few trees in the field.”
Crowther also said the potential to grow trees alongside crops such
as coffee, cocoa and berries – called agro-forestry – had not been
included in the calculation of tree restoration potential, and neither
had hedgerows: “Our estimate of 0.9bn hectares [of canopy cover] is
reasonably conservative.”
However, some scientists said the estimated amount of carbon that
mass tree planting could suck from the air was too high. Prof Simon
Lewis, at University College London, said the carbon already in the land
before tree planting was not accounted for and that it takes hundreds
of years to achieve maximum storage. He pointed to a scenario from the
Intergovernmental Panel on Climate Change 1.5C report of 57bn tonnes of
carbon sequestered by new forests this century.
Other scientists said avoiding monoculture plantation forests
and respecting local and indigenous people were crucial to ensuring
reforestation succeeds in cutting carbon and boosting wildlife.
Earlier research by Crowther’s team calculated that there are currently about 3tn trees in the world,
which is about half the number that existed before the rise of human
civilisation. “We still have a net loss of about 10bn trees a year,”
Crowther said.
The Australian icon could lose its fight against climate change, disease, habitat destruction and cars — but not if dedicated conservationists get the tools they need to protect the species.
Photo: University of Sydney
Ten years ago the shaky video of a dehydrated, wildfire-damaged koala captured headlines and the world’s attention.
Crouched next to a charred tree trunk, a volunteer firefighter named
David Tree gingerly poured bottled water into the open mouth of the
burned koala. A tiny gray paw rested in his own large, calloused hand,
allowing the animal to remain upright as she drank.
The young koala, later nicknamed “Sam,” quickly became the iconic
emblem of the fires — the first stages of what would be known as the
Black Saturday bushfires that burned through the forests of southeastern
Australia in February 2009. The fires occurred during a massive
heatwave. They burned more than 1.1 million acres, killed 180 people,
and caused more than 1 million animal fatalities.
Sam, who was lucky to survive, received treatment at a nearby wildlife center for second-degree burns.
Unfortunately she didn’t last long. Veterinarians soon discovered she
was also suffering from severe cysts caused by inoperable chlamydia, one of a few diseases plaguing wild koalas. With no other options, Sam was euthanized that August.
Today her remains reside at the Melbourne Museum, where she serves as
a symbol of not only the bushfires but the multitude of threats facing
Australia’s wild koalas.
Those threats have taken a terrible toll on koalas (Phascolarctos cinereus), which once numbered in the millions. This May the nonprofit Australian Koala Foundation announced that the marsupials’ wild populations have fallen below 80,000 individuals and the species may now be “functionally extinct.”
In this case “functionally extinct” means that populations have been
reduced so drastically that the animals no longer play a significant
role in the ecosystem.
The news made headlines, but other biologists countered that while
koalas have declined tremendously, the Australian endemics have not yet
reached functional extinction. Regardless, koalas are indeed facing a
whammy of threats in the country, and without serious and timely
intervention it might not be long before the marsupial goes the way of
another famous Australian animal, the extinct Tasmanian tiger.
But even as the koala’s decline continues, many people are stepping
up to help — and what they’re learning may help the species survive the
newest threat from climate change.
A History of Decline, an Uncertain Future
The koala was once ubiquitous in eastern Australia, ranging from tall eucalyptus forests to low woodlands and coastal islands.
Even today “they cover a huge geographic range,” says Christine
Hosking, a koala biologist at the University of Queensland’s Global
Change Institute. Indeed koalas can still be found in all four of the
country’s six eastern states, although their remaining habitats have
shrunk and become fragmented from each other, and many sites hold
increasingly few animals.
“Population sizes vary from place to place,” Hosking says. “That’s
why you can’t come up with a statement saying they’re all functionally
extinct. However, some pockets aren’t doing so well.”
The decline was a long time coming. The fur trade was the first to decimate the koala population. Between 1890 and 1927, more than 8 million pelts were exported to England, according to research compiled by the Australian Koala Foundation.
Habitat loss followed. Eucalyptus groves were bulldozed for suburbs.
People moved in. If the koalas weren’t killed by cars when crossing
roads, they’d be found dangling in the jaws of pet dogs.
A koala injured by powerlines. Photo: Ausgrid (CC BY 2.0)
Then came chlamydia, thought to have crossed over to koalas from
imported sheep and cattle. The marsupials are keenly susceptible to the
sexually transmitted disease, especially when stressed by other factors.
In some areas more than 50 percent of koalas exhibit symptoms, which
can often prove fatal in its late stages. Climate change and heat
stress, therefore, are only the latest in a series of unfortunate events
for the vulnerable koala.
Hosking conducts scientific models to understand how climate change
has and will affect the koala’s range. She’s found that koalas, already
facing reduced and fragmented habitats, will likely now move eastward to
the coast, which has a more moderate climate compared to the inland
areas increasingly experiencing extreme heat and drought.
“The farther you go inland, there’s already evidence of koala populations crashing by as much as 80 percent,” she explains.
Koalas, it turns out, can’t handle the heat. “We did some modeling on
the thermoregulation of koalas and found that over 37 degrees Celsius
(98.6 degrees Fahrenheit) seems to be about their threshold.” As the
climate changes, Australia frequently experiences 10 days in a row of 45
degrees Celsius (113 degrees Fahrenheit). “They’re not coping with that
at all. There’s heat stress, lack of water, and their food trees are
drying out,” says Hosking.
But moving east also means moving into more urbanized areas. That’s
why scientists are hoping to mitigate this migration, using new tools to
save the species.
Drink Up
Koalas get most of their moisture from eating juicy eucalyptus leaves, but they’re limited by how much they can eat.
“Not only are these leaves not particularly nutritious, they’re full
of toxins,” explains Valentina Mella, a researcher at the University of
Sydney. Koalas have developed a specialized intestinal tract to deal
with the toxins, but, they have to wait until they’ve digested the
toxins before eating more. “If you’re thirsty and there’s no water, it’s
not as simple as, ‘I’ll just have another bunch of leaves.’ ”
Can human assistance help koalas get past that biological limitation?
In 2016 Mella and her team placed 10 pairs of drinking stations across
the Liverpool Plains in New South Wales, an area where koalas hadn’t
been doing well. They wanted to see if the marsupials would supplement
their all-leaf-diet with water found in tanks on the ground and in
trees. To her surprise, when presented with the opportunity, the koalas
were enthusiastic drinkers. Mella documented more than 600 visits by
koalas during the course of a year. Other species such as sugar gliders,
brushtail possums, kangaroos and echidnas also took advantage of the
tanks. During hot and dry periods, the koalas chugged down even more.
This gives Mella hope that conservationists might be able to help the
species by maintaining water stations in the wild for koalas — something
that’s already done in rangeland for domestic cattle. Based on this
research, the New South Wales government has already adopted water
stations as a strategy to assist koalas during heatwaves and droughts
Dr. Valentina Mella with a koala joey during research fieldwork Gunnedah, NSW. Photo: University of Sydney
The next step, Mella says, will be to assess exactly how the water stations affect the overall health and survival of koalas.
“On the properties where we have these stations, we check on the
‘regular drinkers’ every six months. So far, they seem to be okay,” she
says. But that’s just in terms of heat and dehydration. “When you add in
the disease situation, then it’s a whole different story. Water is not a
medicine. It can’t cure. But it probably helps in terms of making the
animal more healthy to fight the infection.”
Medicine for Marsupials
To help koalas battling disease, dog bites, and automobile collisions, koala hospitals still play an essential role.
At the Port Macquarie Koala Hospital in New South Wales, about 200
koalas pass through the facility every year. That’s down from around 300
in previous years. “There are just fewer koalas now,” says Cheyne
Flanagan, clinical director at the hospital.
Of the koalas that come in with chlamydia, about 40 percent are
euthanized due to severe damage to their urogenital tracts. The other 60
percent can be treated with antibiotics or surgery. In addition to
affecting internal organs, chlamydia also affects koalas’ eyes, causing
infections or an overgrowth of tissue.
Recovering in a koala hospital. Photo: Tobias Spaltenberger (CC BY-SA 2.0)
“We’ve made progress,” says Flanagan. “It’s definitely better than it
used to be because a lot of research is going on. We’ve learned what
drugs are knocking chlamydia down. You can never cure chlamydia… but you
can put it in remission and sometimes, if the koalas are healthy
enough, their own immune system kicks in and keeps it under control.”
Antibiotic treatment has been problematic in the past because it
often kills the gut microbes that allow koalas to eat eucalyptus leaves.
But scientists have recently discovered one particular protective
microbe that, if kept alive, allows the koala to survive the course of
antibiotics. Researchers are also working on alternative treatments,
such as fecal transplants, probiotics and a chlamydia vaccine.
Yet pressure on state and federal government from the international
community, Flanagan says, is still critical. “Some of the laws for
biodiversity in this country are disgusting.”
Australia’s Federal Failure, a Local Opportunity
Before the federal election in May, koala conservationists had hoped
to turn the tide after decades of apparent governmental neglect.
In its press release ahead of the vote, the Australian Koala
Foundation wrote that it had spent 31 years working with “13 environment
ministers, many of which could be described as the ‘Who’s Who’ of the
political elite and nothing has happened except dead koalas in the wild…
No one has written anything to protect the koala in the last six years
of government.” A national recovery plan, mandated by law, has never
been established. Notably, Australia’s Department of Environment and
Energy web page for koalas
still says, as of this writing, that the planned publication date of a
recovery plan for the species “is expected to be late 2014.”
Further federal progress seems unlikely. On May 18 Australian
citizens re-elected the Liberal-National Coalition, notorious for its
refusal to sharply reduce carbon emissions and coal. Opposing parties
had made far bolder promises on addressing climate change.
Though the federal election was a disappointment to most
environmentalists, Hosking notes it’s now up to local and state
governments to play the bigger roles in koala conservation.
“There’s a lot of lobbying going on with local government,” she says.
“And we’re trying to engage more with state-level governments right now
to come up with strategies to protect the koalas. It’s a matter of
keeping populations viable, allowing them to move safely and stay
healthy. It’s really difficult. It’s gloomy. But it’s certainly not
over.”
