Australian researchers set record for carbon dioxide capture

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Researchers from Monash University and the CSIRO have set a record for carbon dioxide capture and storage (CCS) using technology that resembles a sponge filled with tiny magnets.

Using a Metal Organic Frameworks (MOFs) nanocomposite that can be regenerated with remarkable speed and low  cost, researchers have developed sponge-like technology that can capture  dioxide from a number of sources, even directly from air.

The magnetic sponge is used to remove carbon dioxide using the same techniques as induction cooktops using one-third of the energy than any other reported method.

Associate Professor Matthew Hill (CSIRO and Department of Chemical Engineering, Monash University) and Dr. Muhammad Munir Sadiq (Department of Chemical Engineering, Monash University) led this research.

In the study, published in Cell Reports Physical Science, researchers designed a unique adsorbent material called M-74 CPT@PTMSP that delivered a record low energy cost of just 1.29 MJ kg-1CO2 , 45 per cent below commercially deployed materials, and the best CCS efficiency recorded.

MOFs are a class of compounds consisting of metal ions that form a crystalline material with the largest surface area of any material known. In fact, MOFs are so porous that they can fit the entire surface of a football field in a teaspoon.

This technology makes it possible to store, separate, release or protect valuable commodities, enabling companies to develop high value products.

“Global concerns on the rising level of greenhouse gas emissions and the associated  has led to renewed calls for emissions reduction and the development of green and renewable alternative energy sources,” Associate Professor Hill said.

“However, existing commercial carbon capture technologies use amines like monoethanolamine, which is highly corrosive, energy intensive and captures a limited amount of carbon from the atmosphere.

“Our research shows the lowest reported regeneration energy calculated for any solid porous adsorbent, including monoethanolamine, piperazine and other amines. This makes it a cheap method that can be paired with renewable solar energy to capture excess  from the atmosphere.

“Essentially, we can capture CO2 from anywhere. Our current focus is for capture directly from the air in what are known as negative emissions technologies.”

For MOFs to be used in CCS applications, it is essential to have materials that can be easily fabricated with good stability and performance.

The stability of M-74 CPT@PTMSP was evaluated by estimating the amount of CO2 and H2O captured and released via the researchers’ magnetic induction swing adsorption (MISA) process over 20 consecutive cycles.

The regeneration energy calculated for M-74 CPT@PTMSP is the lowest reported for any solid porous adsorbent. At magnetic fields of 14 and 15 mT, the regeneration energy calculated for M-74 CPT was 1.29 and 1.44 MJ kg CO2-1.


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New material captures carbon dioxide

What Causes Climate Change?

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Graph providing evidence that atmospheric CO2 has increased since the Industrial Revolution

  

 

    

Who emits the most CO2?

 

     

   

      

    

  

Seabed fossils show the ocean is undergoing a change not seen for 10,000 years

ocean circulation may have caused a shift in Atlantic Ocean ecosystems not seen for the past 10,000 years, new analysis of deep-sea fossils has revealed.

This is the striking finding of a new study led by a research group I am part of at UCL, funded by the ATLAS project and published in the journal Geophysical Research Letters. The shift has likely already led to political tensions as fish migrate to colder waters.

The climate has been quite stable over the 12,000 years or so since the end of the last Ice Age, a period known as the Holocene. It is thought that this stability is what allowed human civilisation to really get going.

In the ocean, the major currents are also thought to have been relatively stable during the Holocene. These currents have natural cycles, which affect where marine organisms can be found, including plankton, fish, seabirds and whales.

Yet climate change in the ocean is becoming apparent. Tropical coral reefs are bleaching, the oceans becoming more acidic as they absorb carbon from the atmosphere, and species like herring or mackerel are moving towards the poles. But there still seems to be a prevailing view that not much has happened in the ocean so far – in our minds the really big impacts are confined to the future.

Looking into the past

To challenge this point of view, we had to look for places where seabed fossils not only covered the industrial era in detail, but also stretched back many thousands of years. And we found the right patch of seabed just south of Iceland, where a major deep sea current causes sediment to pile up in huge quantities.

Scientists gathered fossils from an area with lots of seabed sediment. Peter SpoonerAuthor provided

To get our fossil samples we took cores of the sediment, which involves sending long plastic tubes to the bottom of the ocean and pushing them into the mud. When pulled out again, we were left with a tube full of sediment that can be washed and sieved to find fossils. The deepest sediment contains the oldest fossils, while the surface sediment contains fossils that were deposited within the past few years.

One of the simplest ways of working out what the ocean was like in the past is to count the different species of tiny fossil plankton that can be found in such sediments. Different species like to live in different conditions. We looked at a type called foraminifera, which have shells of calcium carbonate. Identifying them is easy to do using a microscope and small paintbrush, which we use when handling the fossils so they don’t get crushed.

Electron microscope image of the tiny fossil plankton G. bulloides, a type of foraminifera found during the study. Alessio Fabbrini, UCLAuthor provided

recent global study showed that modern foraminifera distributions are different to the start of the industrial era. Climate change is clearly already having an impact.

Similarly, the view that modern ocean currents are like those of the past couple of thousand years was challenged by our work in 2018, which showed that the overturning “conveyor belt” circulation was at its weakest for 1,500 years. Our new work builds on this picture and suggests that modern North Atlantic surface circulation is different to anything seen in the past 10,000 years – almost the whole Holocene.

The effects of the unusual circulation can be found across the North Atlantic. Just south of Iceland, a reduction in the numbers of cold-water plankton species and an increase in the numbers of warm-water species shows that warm waters have replaced cold, nutrient-rich waters. We believe that these changes have also led to a northward movement of key fish species such as mackerel, which is already causing political headaches as different nations vie for fishing rights.

Members of the team collect ocean sediment. Ian Hall, Cardiff UniversityAuthor provided

Further north, other fossil evidence shows that more warm water has been reaching the Arctic from the Atlantic, likely contributing to melting sea ice. Further west, a slowdown in the Atlantic conveyor circulation means that waters are not warming as much as we would expect, while furthest west close to the US and Canada the warm gulf stream seems to be shifting northwards which will have profound consequences for important fisheries.

One of the ways that these circulation systems can be affected is when the North Atlantic gets less salty. Climate change can cause this to happen by increasing rainfall, increasing ice melt, and increasing the amount of water coming out of the Arctic Ocean. Melting following the peak of the Little Ice Age in the mid 1700s may have triggered an input of freshwater, causing some of the earliest changes that we found, with modern climate change helping to propel those changes beyond the natural variability of the Holocene.

We still don’t know what has ultimately caused these changes in ocean circulation. But it does seem that the ocean is more sensitive to modern climate changes than previously thought, and we will have to adapt.

The Case for Climate Pessimism

Kena Betancur/Getty Images

A frightening report on climate change has some experts pondering the perils of optimism about the future.

Carbon Dioxide Reached a New High in Humanity’s Existence

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Illustration for article titled Carbon Dioxide Reached a New High in Humanitys Existence
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We’re not even through the first month of 2020, and we already broke the record for the day with the most carbon dioxide in all of human history.

Carbon dioxide in Earth’s atmosphere hit 415.79 parts per million (ppm) at Mauna Loa Observatory on Tuesday. It’s not surprising carbon dioxide levels hit a new daily high, but the new atmospheric record underscores the fact that carbon emissions are rising to new all-time highs when they need to be dropping.

Atmospheric carbon dioxide follow seesaw pattern over the course of a year, rising from fall into spring as plants decay and then declining over the summer as plants grow and suck carbon out of the atmosphere. The cycle has been driven by natural processes for all of human existence until the world began emitting carbon dioxide. Now, the seesaw still exists but it’s been steadily rising with each passing year of continued carbon emissions. The daily record on Tuesday recorded at Mauna Loa Observatory, the gold standard of measuring sites, is an indicator of more records to come in the next few months. The monthly carbon dioxide record is usually set in March or April, though last year’s happened in February owing to human activities that burn fossil fuels.

Scientists can take a long view of carbon dioxide by looking at air trapped in ice cores to understand what the atmosphere of the past looked like. Those record stretch back 800,000 years, as long as humans have walked the Earth. For most of those 800,000 years, average carbon dioxide levels stayed beneath 280 ppm. Things started changing quickly during the industrial era, when humans started burning fossil fuels. The atmosphere humanity has created to day pre-dates our very existence by millions of years.

Despite the clear risks a more carbon dioxide-laden atmosphere poses, emissions are rising faster and faster. As long as humans continue emitting carbon, we’re guaranteed to keep setting new milestones. Just last May, we crossed 415 ppm for the first time ever. That record topped the previous one, which we hit just three months prior. We never even crossed 400 ppm before 2015.

All this carbon is heating up the planet, which is increasing the odds and intensity of heat waveswildfiresstorms and floods. It’s also ruining our air quality, causing public health crises, and even making it harder to think. All the while, science continues to show the risks have never been clearer of what will happen if humanity keeps emitting carbon.

Researchers warn that we’re approaching key tipping points that can trigger runaway global warming and fundamentally disrupt the planet’s climate system. Old Arctic sea ice is on the brink of disappearing. On land, massive ice sheets in Antarctica face the risk of unstoppable collapse and could raise sea levels 10 feet or more. And as forest become more prone to burning, some are beginning to emit carbon and worsening the climate crisis. All this, combined with continued carbon emissions, means we’re headed for even more climate devastation.

We can still change that. It will take radical changes to the global economy, which won’t be easy. But the alternative is complete catastrophe.

Greta Thunberg hits back after Mnuchin says she should study economics at college

KEY POINTS
  • “My gap year ends in August, but it doesn’t take a college degree in economics to realise that our remaining 1,5° carbon budget and ongoing fossil fuel subsidies and investments don’t add up,” the 17-year-old said via Twitter.
  • Her comments come shortly after Treasury Secretary Steven Mnuchin criticized her financial credentials at the World Economic Forum.
  • Thunberg, alongside 20 other young climate activists, had called on the world’s decision-makers and business leaders to stop all investments in fossil fuel exploration and extraction.
VIDEO01:35
Mnuchin criticizes climate activist Greta Thunberg: ‘Who is she?’

DAVOS, Switzerland — Swedish climate activist Greta Thunberg hit back at Steven Mnuchin on Thursday, after the Treasury Secretary suggested she needed to study economics at college before lecturing the U.S. on fossil fuel investments.

“My gap year ends in August, but it doesn’t take a college degree in economics to realise that our remaining 1,5° carbon budget and ongoing fossil fuel subsidies and investments don’t add up,” the 17-year-old said via Twitter.

“So either you tell us how to achieve this mitigation or explain to future generations and those already affected by the climate emergency why we should abandon our climate commitments,” she added.

Greta Thunberg

@GretaThunberg

My gap year ends in August, but it doesn’t take a college degree in economics to realise that our remaining 1,5° carbon budget and ongoing fossil fuel subsidies and investments don’t add up. 1/3

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Mnuchin had criticized Thunberg’s financial credentials at the World Economic Forum earlier in the day.

Speaking to reporters during a press briefing, Mnuchin was asked whether the world’s largest economy should completely and immediately divest from fossil fuels.

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Swedish climate activist Greta Thunberg attends a session at the Congres center during the World Economic Forum (WEF) annual meeting in Davos, on January 21, 2020.
FABRICE COFFRINI | AFP via Getty Images

That’s because Thunberg, alongside 20 other young climate activists, had called on the world’s decision-makers and business leaders to stop all investments in fossil fuel exploration and extraction.

“Is she the chief economist or who is she? I’m confused,” Mnuchin said, before adding this was “a joke. That was funny.”

“After she goes and studies economics in college she can come back and explain that to us,” Mnuchin said.

Carbon budget

An intensifying climate crisis is top of the agenda in Davos, Switzerland.

It follows a 12-month period that saw the hottest year on record for the world’s oceans, the second-hottest year for global average temperatures and wildfires from the U.S. to the Amazon to Australia.

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Steven Mnuchin addresses his comments about environmental activist Greta Thunberg

Earlier in the week, Thunberg cited the International Panel on Climate Change report from 2018 as she delivered remarks to a packed audience.

The IPCC report states the remaining carbon budget would need to fall below 570 gigatons of carbon dioxide in the coming years if the world is to have a 67% chance of limiting global warming to 1.5 degrees Celsius.

“With today’s emissions levels, the remaining budget is gone in less than eight years,” Thunberg said Tuesday. “These aren’t anyone’s views. This is the science.”

Thunberg was catapulted to fame for skipping school every Friday to hold a weekly vigil outside the Swedish Parliament in 2018.

It sparked an international wave of school strikes — also known as “Fridays for Future” — with millions of children taking part in rallies around the world.

US environmental policies are ‘misunderstood’

When asked to address his comments about Thunberg on CNBC’s “Squawk Box” on Thursday, Mnuchin said: “Let me just comment because obviously the climate issue is something that is being talked about this week.”

“And I think, quite frankly, our environmental policies are misunderstood. The president absolutely believes in clean air and clean water. He supports a clean environment.”

President Donald Trump has often expressed skepticism about the scale of the climate crisis and on Tuesday, he urged participants of the forum to reject the “perennial prophets of doom.”

The U.S. president did not name anyone directly during his speech, but he did encourage those in attendance to ignore environmental “alarmists” and their “predictions of the apocalypse.”

Since coming to power in 2016, Trump has taken steps to pull the U.S. — one of the world’s leading carbon emitters — out of the Paris Agreement and sought to roll back over 80 environmental regulations.

“If you look at the real environmental issues right now, they are in China, they are in India. If you look at what the U.S. has been doing on its own, without government intervention, industry has gotten a lot more efficient on carbon emissions,” Mnuchin said.

How bad can the climate crisis get if Trump wins again?

US greenhouse gas emissions are up since 2017 and Trump’s administration has ripped up curbs on climate polluters

A person wears a Donald Trump mask during the ‘March for Climate’ demanding action against climate change during the COP25 Climate Summit in Madrid, Spain, in December 2019.
 A person wears a Donald Trump mask during the ‘March for Climate’ demanding action against climate change during the COP25 Climate Summit in Madrid, Spain, in December 2019. Photograph: Kiko Huesca/EPA

Climate pollution in the US is up under Donald Trump and threatens to undermine international efforts to stall the crisis, especially if he wins re-election this year and secures a second term in the White House.

While US climate emissions fell 2.1% in 2019, they rose significantly in 2018, according to estimates from the economic analysis firm Rhodium Group. On net, emissions are slightly higher than in the beginning of 2017, when Trump’s administration began enacting dozens of environment rollbacks aimed at helping the oil and gas industry.

Trump is still working to further weaken bedrock standards. This week he proposed to allow major projects like pipelines and highways to bypass reviews of how they will contribute to global warming. The draft rule is unlikely to become final before the November election, but it is yet another reason industries weighing climate choices might delay significant action.

“What they have done is created confusion within the business community and the environmental world as to what are going to be the standards,” said Christine Todd Whitman, who led the Environmental Protection Agency under the Republican president George W Bush. “Essentially every regulation the agency promulgates gets a lawsuit that goes with it, almost inevitably … that’s the only good thing you can say about it.”

Whitman called the approach “mindless” and said “whoever is a bigger donor gets to tell them what the environmental policy should be, it seems”.

In the absence of any federal climate action, states, cities and businesses have pledged their own efforts, seeking to encourage other big emitters like China and India to continue to slow their growing climate pollution.

Andrew Light, a climate negotiator for President Barack Obama’s state department, said the world is taking note of those efforts, but if Trump is re-elected “you are going to see a lot of people who are worried anew about what the US can do.”

Americans choosing Trump would send the signal that they don’t care about the climate, Light said.

America’s Pledge, a project to quantify ongoing US emissions reductions, estimates that non-federal actors – like states and cities – could cut climate pollution 37% below 2005 levels by 2030. A Democrat in the White House could increase that to 49% with what Light described as modest, politically achievable policy changes. Experts are increasingly calling for the US to halve its emissions by 2030 and neutralize them by 2050.

“In the case of a second Trump term, we’ve got to totally double down on the efforts to communicate how serious the non-federal actors are in the United States,” Light said. “And what you really want to try to make sure is that those people in other countries who are not in favor of strengthening their countries’ own climate target are not able to point to the United States and say nothing’s going on there.”

The Trump administration has initiated essentially all of its planned climate rollbacks – from weakening standards for cars to go farther on less gasoline to erasing rules for power companies to shift away from coal. It would be able to defend those changes in court against environment advocates and Democratic states if the president wins election.

“The biggest impact of a second term of a Trump administration would just be more lost time,” said Trevor Houser, a partner at Rhodium Group. “It would be more time in which emissions weren’t really declining when they really needed to be.”

The concentration of climate-heating greenhouse gases is at a record high, according to a report from the UN’s World Meteorological Organization. The planet is already 1C hotter than it was before industrialization.

A train of loaded coal cars heads to the Oak Creek power plant in Oak Creek, Wisconsin, earlier this month.
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 A train of loaded coal cars heads to the Oak Creek power plant in Oak Creek, Wisconsin, earlier this month. Photograph: Tannen Maury/EPA

Three-quarters of the commitments made by countries under the international Paris agreement are “totally inadequate”, according to a comprehensive expert analysis. Temperatures are still rising and the world is “gravely” unprepared for disasters, crop failures, coastal flooding and heatwaves, according to another review.

Under Trump, the oil and gas industry contributing heavily to the climate crisis is thriving. Oil and gas-related industries in the US are planning to build 157 new or expanded plants and expand drilling over the next five years – releasing as much greenhouse gas pollution as 50 new coal-fired power plants, according to a report from the Environmental Integrity Project.

As the technology for retrieving oil and gas has advanced, with hydraulic fracturing, the cost of production has plummeted. The US is now a net exporter of oil products.

Much of the expansion expected would be for feedstocks to make chemicals and plastics, explained Courtney Bernhardt, the group’s research director.

Bernhardt said the oil and gas expansion would erase about 75% of the progress in the power sector since 2012.

“The US is already struggling to meet climate commitments and transition to a low-carbon future,” Bernhardt said. “This analysis shows that we’re heading in the wrong direction and really need to slow emissions growth from the oil, gas and petrochemical industries.”

It’s not just climate change that is getting worse. Trump has loosened rules for clean water and air and safer chemicals. Air quality is already eroding, linked with 10,000 additional US deaths over two years.

Democrats, meanwhile, are offering a starkly different future for the environment. The House energy and commerce committee last week introduced a discussion draft of legislation for the US to achieve a “100% clean economy” by 2050.

In the race against Trump, all the major Democratic candidates have similarly pledged to seek at least net-zero emissions by 2050.

The League of Conservation Voters’ called the House committee effort encouraging and said the announcement “is further proof that elections have consequences”. But other groups were critical, saying the plan would not transition away from fossil fuels fast enough.

We’re Getting a Clearer Picture of the Climate Future — and It’s Not as Bad as It Once Looked

Photo: NASA/The LIFE Picture Collection via Getty Images

For once, the climate news might be better than you thought. It’s certainly better than I’ve thought.

You may not have noticed it, amid the flood of bad news about the “Emissions Gap” and the collapse of the COP25 climate conference in Madrid, but over the last few weeks a new narrative about the climate future has emerged, on balance encouraging, at least to an alarmist like me. It is this: As best as we can understand and project the medium- and long-term trajectories of energy use and emissions, the window of possible climate futures is probably narrowing, with both the most optimistic scenarios and the most pessimistic ones seeming, now, less likely.

That narrowing contains both good and bad news — what was recently the best to hope for now seems vanishingly unlikely, and what was the worst to fear much less likely, too. But let’s start with the good news, since there is typically so little of it.

A few weeks ago, the International Energy Agency released its annual World Energy Outlook 2019. The IEA is not known to be optimistic, at least to climate advocates, who have, for years, mocked its projections for future renewable growth: Every year, the agency basically predicts a plateau for renewable use, and every year renewables keep dramatically growing. This made the most noteworthy prediction in this year’s report even more so. According to the IEA report, given only current carbon policies, which nearly everyone studying climate considers terribly weak, the world is on track for about 3 degrees Celsius of warming by 2100, which could, if existing pledges were implemented, be brought down as low as 2.7 degrees — about one and a half degrees less warming than is suggested by the U.N.’s IPCC reports in what is often referred to as the “business as usual” “RCP8.5” scenario.

Now, bear with me, because this is going to get a bit technical, but, I promise, it really does matter. That RCP8.5 scenario is one of four included by the IPCC in their last major assessment report, in 2014, to model possible paths forward — the worst one, tracing the highest arc of emissions and warming outcomes this century. It has shaped a lot of scientific research conducted in the interim; a very common approach is for a particular paper to highlight projected climate impacts in a low-end emissions scenario (either 1.5 degrees or 2 degrees Celsius) and a high-end one (somewhere in the neighborhood of 4 degrees), then describe the low-end outcome as the climate future “if we achieve the goals of the Paris accords” and the high-end one as “business as usual.”

Those deep in the weeds always knew there was something misleading about that characterization, but especially in the aftermath of that IEA report, a very public conversation began, especially on “climate Twitter,” outlining the deep — and perhaps fatal — problems with using RCP8.5 in that way. To begin with, three of the four climate scenarios in the IPCC report were originally devised as “business as usual” scenarios, because none of them reflected, at first, meaningful climate policy.

The assumptions about those factors represent a variety of different no-policy futures, each reflecting different assumptions about the way the world’s energy systems and economies will evolve over the next decades. And the assumptions about those factors which are baked into RCP8.5 seem, by the year, more and more implausible — chiefly that global coal use, which is growing slowly, would dramatically increase over the rest of the century. Given that China is still opening new coal plants, and much of the developing world has yet to reach levels of prosperity where energy use explodes, some growth in coal is probably inevitable, perhaps even dramatic growth. But by 2100, RCP8.5 would require 6.5 times as much global coal use as we have today. That may be possible, given how much we don’t know about the path developing nations in south and southeast Asia and sub-Saharan Africa will take. But given recent drops in renewable pricing, and the positive signs for coal decline in the developed world, as a prediction about energy use RCP8.5 is probably closer to a “worst case,” outlier scenario than anything it would be fair to call “business as usual.”

To be clear, the IEA report only measured emissions from energy use, which is not at all the whole picture when it comes to emissions. RCP stands for “representative concentration pathways,” and theoretically climate feedback loops and other natural processes could deliver those carbon concentrations even if coal use fails to grow at the predicted rate. And it is also the case that some climate impacts are already as bad or even worse than RCP8.5 imagined they could be — arctic ice melt, for instance, including in Greenland, where the ice sheet is melting seven times faster than it was in the 1990s. Plus, the IEA only projects out to 2040, leaving large uncertainties about what would come in the second half of the century. But in a remarkably insightful paper published by the Breakthrough Institute on Wednesday — “in a right and just world, this would be the most high-impact piece of climate writing of the month of December,” the Niskanen Center’s Joseph Majkut said on Twitter — Zeke Hausfather and Justin Ritchie modeled the remainder of the century based on some very conservative assumptions. In one scenario, they assumed emissions would peak in 2040 and hold steady rather than decline until 2100; in the other, they assumed emissions would steadily grow from 2040 until the end of the century. They ran those emissions figures through the IPCC’s own basic temperature calculator and found “that transitions in the global energy system over the past decade mean that a conservative business-as-usual projection of current trends in the energy system continuing is now likely to lead to warming of around 3C by 2100.” Further, while they acknowledge a higher-emissions world than the IEA projects is possible, they conclude that “it may be possible under an optimistic business-as-usual case to have as little as 2.5C warming by the end of the century, though anything below that is very unlikely to happen in the absence of policy given the rate of emissions reductions required.”

I’ve spent the last few weeks trying to wrap my head around all of this, speaking with energy analysts and climate scientists (including Hausfather) about just what these projections mean for our understanding of where we are headed. Nearly every one has told me the IEA projections, while limited in ways, nevertheless represent a more plausible projection of the medium-term energy future than is contained in RCP8.5. Most — though not all — told me that they did not see RCP8.5 as a plausible scenario, even in the absence of meaningful climate policy. Honestly, this surprised me; while objections to RCP8.5 have been around for a decade or more, those who view it skeptically now seem to outnumber those who see it as useful — at least as a vision of a “business as usual” future.

That’s the good news. But it is not, in the end, simple good news. To begin with, there is not corresponding good news in all the other sectors of emissions — agricultural, transportation, industry. Additionally, the single-figure of 3C is a little misleading, since it is only a median projection, as the Breakthrough authors fully acknowledge; their analysis actually finds, using the IEA projections, a range of possible warming levels, from 1.9C to 4.4C (the high-end figure ultimately not very different from RCP8.5’s projections). On top of which, a next generation of more advanced models are currently being developed to better predict what amount of temperature rise would result from certain emissions levels, and while the models are by no means speaking in unison, a concerning proportion of those that have been released show that the climate could be considerably more sensitive to emissions than previously understood — meaning we could find ourselves in a better place, emissions wise, this century, and still end up in roughly the same place we thought we would, when we were expecting higher emissions. (Or perhaps, in theory, even a worse place.)

But the worst news from recent calculations is not about how much we should be lowering our high-end estimates for what amount of warming is possible, but that we have to simultaneously raise our floors. As this animation usefully shows, we are practically already at the limit of our “carbon budget” for 1.5 degrees Celsius:

The math — ten years left at current emissions — is actually bleaker than it might seem at first, since running through ten years at the current rate would only land us at 1.5 degrees if, immediately thereafter, we went all the way to zero, never again emitting another ounce of carbon, let alone a gigaton, of which we are today producing, from industrial processes and fossil-fuel burning, 37 each year. A gigaton is, keep in mind, a billion tons. Which makes not just 1.5 degrees but, I think, 2 degrees, for all practical purposes out of reach. As a reminder, this is a level of warming that the IPCC has called “catastrophic” and the island nations of the world have described as “genocide.”

This may all seem dizzyingly complicated on-the-one-hand-and-on-the-other inside baseball climate talk. But four big takeaways suggest themselves — to me, at least.

The first is that, for all of our earned confidence in the present state of scientific understanding of climate change, there is enormous uncertainty about human response to the challenge of warming. There is a reason the IEA sunsets its projections at 2040 — it’s because projecting things further out is, ultimately, a foolish game. Energy projections as recent as the pre-fracking 2000s are already very much out of date; even more so for those made during the 1970s and 1980s. Projecting what global energy use will be in the year 2100 is the equivalent of trusting projections made in 1940 about where we are today.

This is especially problematic because, ultimately, that range of inputs — how much carbon we put into the atmosphere over the next decades — is the major determinant of warming levels. We can know, with pretty good if not absolute confidence, that putting X amount of carbon into the atmosphere will produce Y amount of warming on a timescale of a century, say. But just how big that X turns out to be is, ultimately, a matter of very gestural guesswork. Whether China’s coal use grows slowly, plateaus and then drops slowly, or drops precipitously over the next two decades — that is not something it is even possible to know, really, though we can guess. Even less possible is knowing whether the next wave of developing nations — India, Indonesia, much of sub-Saharan Africa — will follow the patterns of energy use of the nations just ahead of them on the economic growth. If coal use grows in other parts of the world as dramatically as it did in China in the 1990s and 2000s… well, there are billions of people in those parts of the world, and a rapid energy expansion there could conceivably bring us a lot closer to RCP8.5 than the IEA (or Breakthrough) suggest.

Perhaps a sixfold increase in coal use seems implausible, globally. But even a steady trajectory of coal emissions — new use in the developing world counterbalancing the growth of renewables elsewhere — would be quite bad, if it extended for decades. The IEA predicts it will remain stable, at least for the time being. Exxon, for its part, predicts no decline in carbon emissions from the energy sector through 2040 — and no point, at all, where they reach zero. (By the way, a little-noticed 2018 methane leak at an Exxon plant in Ohio was recently found to have released more of the powerful greenhouse gas than the entire oil and gas industries of many countries.) And we do of course have enough carbon on the planet to reach RCP8.5, should we choose to burn it.

The second takeaway is that anyone, including me, who has built their understanding on what level of warming is likely this century on that RCP8.5 scenario should probably revise that understanding in a less alarmist direction. Scientists who are studying particular impacts should probably stop using RCP8.5 as a stand-in for “no policy” or “business as usual” climate trajectories, and certainly stop describing research that does use it as reflecting a “business as usual” world. We could still get to an RCP8.5-like situation, theoretically, but it is pretty unlikely, and would probably require a departure from the blithe stumbling-down-our-current-path-blindly pattern of the last few decades. This is all, absolutely, cause for optimism, even if it is optimism in the face of great uncertainty. (In climate, we’ll take what we can get.)

The third takeaway is that anyone who sees a world of 3 degrees warming — or even 2.5 degrees — as a positive or happy outcome has a pretty grotesque, or at least deluded, perspective on human suffering. At just two degrees, the U.N. estimates, damages from storms and sea-level rise could grow 100-fold. Cities in South Asia and the Middle East that are today home to many millions of people would be so hot during summer heat waves, scientists have projected, even going outside during the day could mean risking heatstroke or heat death. The number of climate refugees could pass 200 million, according to the U.N., and more than 150 million would die from the impacts of air pollution alone. North of two degrees, of course, the strain accumulates and intensifies, and while some amount of human adaptation to these forces is inevitable, the scale of adaptation required at even two degrees begins to seem close to impossible.

The fourth is that these findings do not, actually, make it look easier to get to “safe” levels of warming — say 1.5 degrees, or even, for that matter, 2. All future emissions paths are charted from the present forward, of course, not from some projected scenario backward. And the state of things is in the present tense is really quite dire — new emissions records every year. To stay safely below 2 degrees, we would still need to roughly halve our carbon output by 2030 and zero it out entirely by 2075, as the U.N. warned last October in its “Doomsday” report. Neither of those tasks look any easier today than they did six months ago, since in fact the world is still moving in the wrong direction, growing our emissions and making more radical future cuts necessary with each passing day. According to the UN’s Emissions Gap report, we now need to cut emissions by 7.6 percent per year every year for the next decade, globally, to hit the Paris targets — a rate faster than any single nation has ever achieved in any single year, pursued globally, including by many countries with populations collectively in the billions pursuing high-energy prosperity for the very first time.

How we respond to these challenges — decarbonization but also the climate impacts brought about by delay — is, of course, another uncertainty, perhaps the most significant one. And even in a year of dramatic political mobilization on climate, on this question, personally, I’ve been growing more concerned that one major response among the world’s well-off, at least, will be normalization, compartmentalization, and continued complacency.

In the spring, I spent some time reporting on life in California under the threat of wildfires — traveling to Los Angeles expecting I’d be seeing a glimpse of our climate future, a city buckled under with climate anxiety, but which I found ultimately to be a journey through normalization and compartmentalization. One woman I met had personally lived through nine fires, a fact I thought about a lot in the months that followed, whenever I found myself considering the problem of climate normalization.

But over the last few weeks, I’ve been thinking more about another encounter, from earlier this fall, one that followed a climate panel I’d just participated in. After the discussion, I was cornered by a middle-aged businessman, who assured me that despite what I might think, he did believe in climate change, then asked, in an almost conspiratorial tone — seeking, it seemed, a kind of a secret answer — “How bad is it going to be?”

It was a bit of a confusing question, after 90 minutes of conversation on stage — a conversation he’d chosen to attend and paid attention to, he pointed out, which he suggested was a self-evident sign that he took the issue seriously.

“Well,” I began, “at just 2 degrees of warming, which is basically a best-case scenario, it’s been estimated that 150 million people would die from air pollution — ”

“But out of 8 billion,” he said quickly, cutting me off and smiling strangely.

“Right,” I said, “I don’t think human extinction or total civilization collapse is likely, though the pressures are going to get pretty intense and we don’t really know how societies will respond. But even if they respond pretty well — I mean, 150 million is 150 million. That’s a lot of people. That’s dying at the scale of 25 Holocausts.”

“But out of 8 billion,” he repeated, smiling, like he’d caught me in a trap. At which point I understood what he’d actually meant by the question he’d posed, and why it was so important to him to get a precise answer. What he was asking was not, how bad is it going to be. What he was asking was, how bad is it going to be for me?

The tragic thing was, in learning about 150 million deaths from air pollution, which were today concentrated in India and China and would likely grow in other areas of the developing world in the future, he seemed to have gotten the comforting answer he was looking for: not that bad, relatively speaking. He walked away triumphantly. I didn’t have the chance to tell him that, just in 2017, pollution killed 197,000 Americans.

The Human Brain Evolved When Carbon Dioxide Was Lower

Pedestrians are seen wearing masks as smoke haze from bushfires in New South Wales blankets the central business district in Sydney.
Australia’s bushfires choked Sydney with soot and have emitted about 195 million tons of carbon dioxide this year, equivalent to half of the country’s normal carbon-emissions footprint.REUTERS
SAN FRANCISCO—Kris Karnauskas, a professor of ocean sciences at the University of Colorado, has started walking around campus with a pocket-size carbon-dioxide detector. He’s not doing it to measure the amount of carbon pollution in the atmosphere. He’s interested in the amount of CO₂ in each room.

“I did this at home, just having fun with it, and in a bedroom overnight it can get over 1,000 parts per million very quickly,” he told me. Even here, he added—gesturing at the city-block-size basement of the Moscone Convention Center, filled with thousands of earth scientists milling about their discipline’s giant annual science fair—the CO₂ probably exceeds 500 parts per million.

“This is a hidden impact of climate change … that could actually impact our ability to solve the problem itself,” he said.

He proposed the idea last week at the American Geophysical Union’s fall meeting, the largest annual gathering of earth and space scientists in the world. He also previewed it in an online paper written with Shelly Miller, a mechanical-engineering professor at the University of Colorado, and Anna Schapiro, a neuroscience professor at the University of Pennsylvania. The paper, while not yet peer-reviewed, was uploaded to a website where academics can discuss early-stage or provocative research.

The science is, at first glance, surprisingly fundamental. Researchers have long believed that carbon dioxide harms the brain at very high concentrations. Anyone who’s seen the film Apollo 13 (or knows the real-life story behind it) may remember a moment when the mission’s three astronauts watch a gauge monitoring their cabin start to report dangerous levels of a gas. That gauge was measuring carbon dioxide. As one of the film’s NASA engineers remarks, if CO₂ levels rise too high, “you get impaired judgement, blackouts, the beginning of brain asphyxia.”

“They knew they’re going to go nuts and not do 2+2 if that gauge gets too high,” Karnauskas said. The same general principle, he argues, could soon affect people here on Earth. Two centuries of rampant fossil-fuel use have already spiked the amount of CO₂ in the atmosphere from about 280 parts per million before the Industrial Revolution to about 410 parts per million today. For Earth as a whole, that pollution traps heat in the atmosphere and causes climate change. But more locally, it also sets a baseline for indoor levels of carbon dioxide: You cannot ventilate a room’s carbon-dioxide levels below the global average.

In fact, many rooms have a much higher CO₂ level than the atmosphere, since ventilation systems don’t work perfectly. On top of that, some rooms—in places such as offices, hospitals, and schools—are filled with many breathing people, that is, many people who are themselves exhaling carbon dioxide. As Karnauskas said: “We’re little CO₂-producing machines ourselves.”

“Imagine a conference room,” he said. “You have middle-aged people—20 of them—sitting in a small room, breathing. That CO₂ easily exceeds 1,000 parts per million.”

And that leads to the final part of his and his colleagues’ argument: As the amount of atmospheric CO₂ keeps rising, indoor CO₂ will climb as well. They project that, in a worst-case emissions scenario, it may be impossible to ventilate a crowded room below about 1,300 parts per million. That could induce some real cognitive damage. In 2016, researchers at Harvard and Syracuse University found that human cognitive function declined by about 15 percent when indoor CO₂ reached 945 parts per million, and crashed by 50 percent when indoor CO₂ reached 1,400 parts per million.

Under a very high carbon-emissions scenario, “our complex decision-making functions could be reduced by as much as half by the end of the century,” Karnauskas said.

He and his colleagues admit that their calculations are back of the envelope. “There’s got to be a lot more work on this,” he told me. And I had to wonder: Is this for real? Why hadn’t I heard about it before? Is carbon pollution not only heating the planet but actually making us more sluggish thinkers?

“Since then, we’ve learned a little bit more, but we know less,” he said. There’s been a surge of studies on the topic in the past few years. What they’ve found is inconsistent.

For instance, in one 2016 study Danish scientists cranked up indoor carbon-dioxide levels to 3,000 parts per million—more than seven times outdoor levels today—and found that their 25 subjects suffered no cognitive impairment or health issues. Only when scientists infused that same air with other trace chemicals and organic compounds emitted by the human body did the subjects begin to struggle, reporting “headache, fatigue, sleepiness, and difficulty in thinking clearly.” The subjects also took longer to solve basic math problems. The same lab, in another study, found that indoor concentrations of pure CO₂ could get to 5,000 parts per million and still cause little difficulty, at least for college students.

But other research is not as optimistic. When scientists at NASA’s Johnson Space Center tested the effects of CO₂ on about two dozen “astronaut-like subjects,” they found that their advanced decision-making skills declined with CO₂ at 1,200 parts per million. But cognitive skills did not seem to worsen as CO₂ climbed past that mark, and the intensity of the effect seemed to vary from person to person.

In September, some of the issue’s leading scientists—including those from the Denmark lab mentioned above—reviewed all 10 studies on the topic since 2012. On moderate tests of cognition, they found, the evidence was very ambiguous: Sometimes higher CO₂ seemed to decrease ability, sometimes it didn’t at all. But more worryingly, they noted “substantial, but still inconsistent, evidence” that human performance can decline on especially challenging problems at moderate concentrations. Pilot performance on flight simulators, for instance, starts to fall at 1,200 parts per million. “The mechanisms underlying the reductions in performance are unknown,” they added.

In other words: There’s evidence that carbon-dioxide levels may impair only the most complex and challenging human cognitive tasks. And we still don’t know why.

In their September review, the authors noted that many aspects of the problem remain unexplored. For instance, does CO₂ make the effects of other brain-impairing pollutants worse? It’s unclear. No one has looked at the effects of indoor CO₂ on children, the elderly, or people with health problems. Likewise, studies have so far exposed people to very high carbon levels for only a few hours, leaving open the question of what days-long exposure could do.

“The unfortunate conclusion,” Gall said, “is, I think the science so far is unsettled for that direct role for CO₂” on human cognition. “Until we pinpoint CO₂ itself as a causative agent, there’s a lot of ways that a changing atmosphere could impact indoor air quality.”

Perhaps the most intriguing omission of the research is also the most ominous. Modern humans, as a species, are only about 300,000 years old, and the ambient CO₂ that we encountered for most of our evolutionary life—from the first breath of infants to the last rattle of a dying elder—was much lower than the ambient CO₂ today. I asked Gall: Has anyone looked to see if human cognition improves under lower carbon-dioxide levels? If you tested someone in a room that had only 250 parts per million of carbon dioxide—a level much closer to that of Earth’s atmosphere three centuries or three millennia ago—would their performance on tests improve? In other words, is it possible that human cognitive ability has already declined? Gall said he wasn’t aware of such an experiment.

But of course, a large-scale experiment is under way—it’s just not happening under clinical conditions. You and I are its subjects, and the CO₂ in the chamber rises with every passing year. Clock your baseline cognition now: In another 20 years, you might miss these clearheaded times.

Climate change: Greenhouse gas concentrations again break records

Power plantImage copyrightGETTY IMAGES

Atmospheric concentrations of carbon dioxide and other greenhouse gases once again reached new highs in 2018.

The World Meteorological Organization (WMO) says the increase in CO2 was just above the average rise recorded over the last decade.

Levels of other warming gases, such as methane and nitrous oxide, have also surged by above average amounts.

Since 1990 there’s been an increase of 43% in the warming effect on the climate of long lived greenhouse gases.

The WMO report looks at concentrations of warming gases in the atmosphere rather than just emissions.

The difference between the two is that emissions refer to the amount of gases that go up into the atmosphere from the use of fossil fuels, such as burning coal for electricity and from deforestation.

Concentrations are what’s left in the air after a complex series of interactions between the atmosphere, the oceans, the forests and the land. About a quarter of all carbon emissions are absorbed by the seas, and a similar amount by land and trees.

This increase was above the average for the last 10 years and is 147% of the “pre-industrial” level in 1750.

The WMO also records concentrations of other warming gases, including methane and nitrous oxide. About 40% of the methane emitted into the air comes from natural sources, such as wetlands, with 60% from human activities, including cattle farming, rice cultivation and landfill dumps.

Methane is now at 259% of the pre-industrial level and the increase seen over the past year was higher than both the previous annual rate and the average over the past 10 years.

Nitrous oxide is emitted from natural and human sources, including from the oceans and from fertiliser-use in farming. According to the WMO, it is now at 123% of the levels that existed in 1750.

Last year’s increase in concentrations of the gas, which can also harm the ozone layer, was bigger than the previous 12 months and higher than the average of the past decade.

What concerns scientists is the overall warming impact of all these increasing concentrations. Known as total radiative forcing, this effect has increased by 43% since 1990, and is not showing any indication of stopping.

deforestationImage copyrightGETTY IMAGES

“There is no sign of a slowdown, let alone a decline, in greenhouse gases concentration in the atmosphere despite all the commitments under the Paris agreement on climate change,” said WMO Secretary-General Petteri Taalas.

“We need to translate the commitments into action and increase the level of ambition for the sake of the future welfare of mankind,” he added.

“It is worth recalling that the last time the Earth experienced a comparable concentration of CO2 was three to five million years ago. Back then, the temperature was 2-3C warmer, sea level was 10-20m higher than now,” said Mr Taalas.

The UN Environment Programme will report shortly on the gap between what actions countries are taking to cut carbon and what needs to be done to keep under the temperature targets agreed in the Paris climate pact.

Preliminary findings from this study, published during the UN Secretary General’s special climate summit last September, indicated that emissions continued to rise during 2018.

Both reports will help inform delegates from almost 200 countries who will meet in Madrid next week for COP25, the annual round of international climate talks.