Direct Air Capture: How the fight against climate change will be won or lost

Fifteen years from now, when the Great Barrier Reef is a thing of the past, when downtown Atlantic City, Bangkok, Boston, Charleston, Dhaka, Galveston, Honolulu, Jakarta, Lagos, Manhattan, Miami, Mumbai, New Orleans, Newark, Rotterdam, San Francisco, Seattle, Tampa, and Venice relocate, and when Australia and California burn, everyone — from farmers to stock brokers, peasants to politicians– will be asking the same question: Are the machines working?

DAC.jpg

Those machines will be sucking carbon out of the air and burying it deep in the ground or under the sea. We don’t know exactly where they will be, what they will look like, or even how well they will work. All we know is that we need them (Lackner et al 2013).

Reducing our carbon emissions, which humans have proved incapable of, is not enough now. Even reducing to zero emissions tomorrow is insufficient. We are too far gone in the wrong direction. What’s more, like a ship heading for the end of the world where the water falls off the edge, our foot is still on the accelerator. Slowing down is good, but insufficient to avert disaster; we must turn the ship around and head the other way. We need to not just reduce emissions, we need to reduce the amount of CO2 already in the atmosphere. That means negative emissions– sucking carbon out of the air.

Direct Air Capture vs Flue Capture; Sequestration vs Re-Use

Carbon capture from ambient air, also called Direct Air Capture (DAC), is different from conventional carbon capture at factory chimney flues (i.e. point source carbon capture). First, it’s a lot easier to capture carbon from flues because the CO2 is concentrated. Second, typically the goal of flue carbon capture is to minimize CO2 emissions and often to re-use the CO2 in a process that reduces the need for fossil fuels. If it is re-purposed, you’ve reduced CO2 emissions from fossil fuels, but the CO2 is still released into the atmosphere. This is a process to reduce emissions; it is not net-negative.

There are also plans to capture carbon, from the air or from flues, and use it in a variety of other industrial processes, from putting bubbles in soda to (wait for it)… extracting more oil. These plans are merely meant to reduce emissions and also to incentivize the private sector to capture carbon. But it’s not net-negative.

Feasibility

Back to direct air capture. Here’s the catch: we don’t know if we can do it at the scale needed. Fortunately, humans have been much better at finding technological solutions than political ones. There are more than a dozen pilot projects in Iceland, Switzerland, and elsewhere showing it can be done– on a very small scale. There are a host of questions, but the biggest challenge is sucking it out of the air in an efficient and cost-effective way.

Funding

Feasibility aside, there’s the question of how to pay for it. Suppose we wanted to capture and sequester 7 billion metric tons of CO2 annually, which is the IPCC goal by 2050. Currently we emit 43 billion. Early estimates are that it would cost $700 billion/year (at $100/ton) and require an enormous amount of energy, up to a 12% of annual worldwide energy use. But those are early estimates. Technology gets better and cheaper with time. The Center for Negative Carbon Emissions at Arizona State University thinks it can be done for $210 billion/yr (using $30/ton) and require only 1% of worldwide energy use.

For context, worldwide military spending is $1.8 trillion/yr (or $1,800 billion), nearly half of which is by the US. If the armies of the world ever wanted to save a city, let alone a village, they have the money to do it.

Ultimately, governments will have to pay for carbon capture and sequestration. There is no way to incentivize the private sector to bury a product rather than re-use it. In the near term, we can benefit from private sector carbon capture and re-use because, although it is not net-negative, it can incentivize research into DAC technology. And it does reduce emissions.

DAC on a meaningful level requires international coordination and, of course, cost sharing. The two most obvious models would be to apportion cost share based on current or past CO2 emissions.

Each nation will likely be up to its own to develop their own funding mechanism. A carbon tax is an obvious solution. If DAC costs $100/ton, that translates to 88 cents/gallon at the pump. Other fossil fuel uses would also have to be taxed as well. While this sounds affordable, there are two complicating factors: 1) we can’t just address the gallons of gas we are buying now; we have to address all the gas we have ever bought and all our parents have ever bought; and 2) carbon taxes are regressive, hitting the poor more than the rich (as a percentage of their income). There are ways around that, a subject for another blog post.

The enormity of the task means that technological innovations to lower the cost are critical. This should not be left to small policy initiatives like research grants and tax incentives. This requires the full weight of all the major governments and universities in the world. Progressive governments in Europe and California (where Democrats have super-majorities in both houses of the legislature) could and should embark on DAC projects immediately.

The Free Rider and Moral Hazard Problems

CO2 released anywhere in the world spreads everywhere, and DAC done anywhere reduces CO2 everywhere. This is both good and bad. It means that DAC can be done anywhere, allowing us to select the most expedient locations. For example, a DAC pilot study in Iceland uses clean geothermal energy to capture carbon and inject it into porous volcanic rocks.

But it also means there’s a potential free rider problem, where countries will shirk their obligations in the hopes that others will take care of it for them. One can imagine rogue nations that refuse to pay their fair share and free ride on the public service provided by other countries. The US, whose share would be large by any measure, is a candidate for such recalcitrant behavior. Public support for DAC could overcome this.

It is possible that Republicans would support DAC. The US Congress recently passed a $50/ton tax credit for DAC removal, the most ambitious such incentive in the world. Republican support, however, probably came from the associated $35/ton tax credit for carbon captured from the air and used for enhanced oil extraction. Regardless, Republicans could see DAC as an opportunity to extend fossil fuel use into the future. And therein lies the moral hazard problem. If we’re doing DAC, one could argue that we don’t need to reduce emissions as much. And if DAC became cheap and easy, fossil fuel use (aside from the spill risks and air quality impacts) could arguably continue.

But, like with a penny saved rather than earned, carbon not emitted is carbon you don’t have to capture and sequester. There are two more reasons why reducing emissions must still happen: 1) at the moment, it’s still cheaper to reduce CO2 emissions than to capture it; and 2) we are nearing the edge of the world, when it’s too late even to capture carbon.

Positive Feedback Loops

This brings us to the gremlins in the room– positive feedback loops. These are additional sources of global warming that are caused by the current global warming. They are force multipliers, accelerators, that can make global warming much worse very fast. It’s hard to predict when they will kick in. If they do, our job will become much much harder. We will lose ground, a lot more ground (read human suffering) before we win. They put victory in doubt.

Some positive feedback loops, such as increased water vapor in the air and dark seas and mountains exposed from melting ice and glaciers, have been accounted for in climate models. More pernicious are the more unpredictable “time bombs”, such as permafrost melt and massive wildfires.

Melting permafrost is the proverbial elephant of the gremlins in the room. Research suggests that rapid methane releases from melting permafrost may have been the final driver in runaway climate change that led to past mass extinction events, including the End-Permian Extinction in which 97% of all life on earth perished. This effect is already happening. NOAA recently reported that melting permafrost now contributes as much as net 0.6 billion tons of carbon (equivalent to 2.2 billion tons of CO2) to the atmosphere each year; “the feedback to accelerating climate change may already be underway.”

Forests are normally carbon sinks, taking in CO2. However, in 2006 Westerling et al warned that “forests of the western United States may become a source of increased atmospheric carbon dioxide rather than a sink, even under a relatively modest temperature-increase scenario.” Since then, wildfires have increased dramatically.

These positive feedback loops are like an increasing current threatening to pull the ship over the falls. If we are waiting for technology to save us, we may have waited too long.

Controlling the Climate

In the long run, Homo sapiens might eventually hopefully maybe win the climate battle and be able to capture and sequester enough carbon to return the earth’s atmosphere to normal conditions. But there will be suffering in the short-term, for the next two hundred years, thru sea level rise, heat waves, droughts, powerful hurricanes, and agricultural disruption. The poor will suffer most. Turning the climate around is like turning a cruise ship. There’s a lot of lag time between cause and effect. That’s why humans have found themselves in the current crisis. Only the scientists saw it coming. Nobody felt the impacts until now, and now it’s too late to avoid them. The same is true regarding corrective measures. A lot of sea level rise, caused by ice melt in Greenland and Antarctica, is already built into the system. It is coming and coming at an increasing and exponential rate. We may have to actually cool the planet beyond the recent historic level to stop it. And that may take 150 years. In the meantime, hundreds of coastal cities will go under water. This appears inevitable, even under the most optimistic scenarios.

The graphs below present the most wildly optimistic scenario, achieving the Paris goal’s peak emission in 2020 (this year), DAC of 7 billion tons of CO2 per year by 2050, plus optimistic net removal thru reforestation and new soil management practices, all of which help to get us to net-zero emissions by 2050, another Paris goal. After that, we remove more than we emit; we are net-negative, returning the earth to under 400 ppm.

It would be great to just use natural approaches to sequester carbon (e.g. reforestation and soil management). But the numbers just don’t add up fast enough. During past global warming events (e.g. the Paleocene Eocene Thermal Maximum), it took the earth’s natural processes tens of thousands of years to restore balance. We have put so much carbon up so fast thru industrial processes that we need the same kind of speed sucking it back in. Nevertheless, looking at the graph below, reduced carbon emissions are still the biggest player, followed by DAC and the natural processes. We need it all to the maximum extent possible as soon as possible.

But this wildly optimistic scenario still has us peaking at 510 ppm in 2050, high enough to hit 2.0 Celsius warming, which is perilously close to unleashing enough carbon and methane from permafrost and other positive feedback loops to launch us toward 3 or 4 or 5 C warming and create another mass extinction event  (which we know from the past the world will recover from, re-evolving new life forms, in a few million years).

DAC chart1.jpg

The graph of CO2 levels below is derived from the assumptions regarding CO2 emissions and removal above. This is a best case scenario.

DAC chart2.jpg

But suppose humanity gets past this. Successful implementation of carbon capture and sequestration would mean that Homo sapiens can control the earth’s climate. That brings with it a host of other questions. At what level do we set atmospheric CO2? Do we return to 300 ppm or lower? Who decides? Because carbon released or captured anywhere affects everywhere, who will police it? These are questions for our children, if they are fortunate.

Buying Greenland: Destroying the planet to make some money

Trump’s apparently serious bid to buy Greenland seemed like something out of The Simpson’s or SNL. It is not. It reveals something far more treacherous, like a ploy concocted by the villain in a superhero comic.

villian.jpg

Setting aside the massive hubris of white privilege, that land and indigenous people can be bought and sold by colonial powers (and Trump has mentioned trading some US land away to make the deal), and setting aside the question of how to pay for it (perhaps by ignoring Congress and diverting funds from another source, like he did for his wall), his proposal means he believes in climate change and wants to profit from it—from the suffering of billions and the destruction of earth as we know it.

It’s not hard to understand the mastermind of Trump. His strategies are as transparent as a third grader’s plotting to steal cookies. At the Arctic Council meeting in May, Secretary of State Mike Pompeo dismissed climate concerns and instead highlighted “new opportunities for trade” created by the melting ice, the “opportunities and abundance” created by an ice-free Arctic. In preparation for the Arctic summit, Pompeo was probably briefed about the economic opportunities of an ice-free Arctic Ocean—not just the shipping lanes but also the massive reserves of oil under the seabed. And perhaps that briefing mentioned Greenland, with massive reserves of coal and uranium and an estimated 13% of the world’s undiscovered oil reserves.

Pompeo shares the information with Trump. Trump offers to buy Greenland. Ca-ching.

They’ve also figured out that Greenland is melting. And it is melting much faster than climate scientists predicted. A new report by NASA revised its estimate of sea level rise from Greenland alone from 3 feet to 5 feet over the next 200 years. During a heat wave last month, it melted at a rate that it was not predicted to reach until 2070. While billions will be underwater, Trump sees opportunity and abundance.

greenlandice.jpg

A dramatic photo of pooling meltwater on sea ice off Greenland. July, 2019.

In the same way he has hijacked the Republican Party and wed it to a small and diminishing demographic (rural white men), he has wedded his personal investment strategy to “disaster capitalism”, a plan to make money off the destruction of the earth. Along with all of Big Oil and the Republican Party, he has a financial conflict of interest with curtailing CO2 emissions. If Greenland was part of his investment portfolio, he’d also have a conflict with solutions to climate change. He’d even have a conflict with a magic technological breakthrough that sequesters carbon. He’d need the ice to melt.

He has become the diabolical villain of superhero cartoons. The desire to make money off the destruction of the earth is not only an impeachable offense, it disqualifies him from any responsible role on the planet. He is a threat to all humanity and the world.

The only superhero to thwart him is us, the unorganized millions. It’s time to stop tweeting about his hair and his wife and his rudeness and his gaffes. It’s time to think strategically and take to the streets. It’s time to make his life a living hell before he does that to the planet.

Faster all the time: The basics of sea level rise

I was lucky to be out of town for a week during “the greatest statewide heat wave ever recorded in California.” When I arrived in Seattle, I was quickly informed that they had just set a record of 55 consecutive days without rain—and that the record would still be increasing had it not been for 0.02 inches late one night a few weeks earlier. Seattle has also set a number of heat records the past four summers. The same people that bragged about this “beautiful weather” scoffed that I believed in climate change. They asserted that no sea level rise would occur during our, our children’s, or our grandchildren’s lifetimes because, 1) Puget Sound was not really part of the ocean; and 2) those NOAA flood maps are “bureaucratic bullshit”.  These same people live on the water in homes that are a few feet above current maximum high tides. Days later we all swept ashes off decks while marveling at the sun, which was reduced to a rosy red disc by smoke from a record 68 large uncontained fires burning across the West.

Astounded by the number of homes, roads, and railroad tracks located just toe-dipping distance above Puget Sound, I set out to learn about sea level rise, talking to experts and reading published studies and reports from the Intergovernmental Panel on Climate Change (IPCC) .  Here are the basics.

  • Increases in sea level lag quite a bit behind climate change. We set the record for the warmest year on earth in 2016, breaking the record from 2015, which broke the record from 2014. For something as variable as weather, which has all kinds of ups and downs, this kind of consecutive record-breaking suggests runaway global warming. It is dramatic. But not so with sea levels.
  • Sea level rise is a function of several different factors:
    1. Thermal expansion: This happens because, like air or most anything else, water expands when it is warmer, taking up more space. As ocean temperatures increase, they bulge up a bit, and the sea level rises. This can be quantified with pretty good precision and is already occurring. In fact, this explains nearly all of the sea level rise currently underway.
    2. Antarctic Ice Sheet: While melting ice in the Arctic Ocean affects weather and ocean currents, it doesn’t add to the sea level because the ice was already in the ocean to begin with. An ice cube that melts in a glass of water does not change the water level. But glaciers that are on land, like in Antarctica, will flow into the sea when they melt, thus adding to sea levels. They are like an ice cube perched on the edge of the glass, melting into it.
    3. Greenland Ice Cap: While not as big as the Antarctic Ice Sheet, the Greenland Ice Cap will melt faster. In fact, it is already becoming the next big contributor to sea level rise.
    4. Other glaciers and other factors: Smaller glaciers from Alaska to New Zealand are melting, and also adding to sea level.
  • Sea level rise is underway, currently at a rate of 3.2 mm/yr (about a foot per 100 years). It has already risen 2 ½ inches since the year 2000, and 6 ½ inches since 1900.
  • The rate of sea level rise is increasing as ice melt from Greenland, Antarctica, and other glaciers begin to contribute. The standard practice is to estimate total sea level rise by the year 2100 as compared to 2000. Because the rate is increasing, it will certainly be more than the one foot described above, because ice melt from Greenland, Antarctica, and other places is just beginning. However, estimating that increase is difficult. The 2013 report from the IPCC estimated total sea level rise by 2100 at 1 foot to 3.2 feet, depending upon assumptions about CO2 levels. Because Greenland and other Arctic glaciers are melting faster than anticipated, the IPCC report has come under criticism from scientists, who have now adjusted their estimates up to 1.7 feet to possibly 6 feet by 2100. (Revision from November 2017:  A new study estimates sea level rise at 6 to 11 feet by 2100.)
sealevel3

The projected range of sea level rise, depicted in scale over a waterfront home.

  • The rate of sea level rise will continue to increase at an increasing rate for several hundred years. The Antarctic Ice Sheet and Greenland have a lot of ice, and melting takes time. This melting, which is only just beginning, will increase with time, but may still take hundreds of years to really pick up steam. This appears to be “virtually certain”. The Antarctic Ice Sheet is now considered to be “past the point of no return”, with large scale melting “unstoppable.” Still, the exact timing is unknown. It will begin slowly but then suddenly increase rapidly, possibly during this century. This caveat is included in all predictions. The “conservative” estimate is that ocean levels will rise 3 to 10 feet by the year 2300, depending upon future CO2 levels and temperature increases. At that point, however, it will still be rising at a rate more than double the current rate. It thus appears that a total sea level rise over 10 feet, largely if not entirely due to anthropogenic CO2 emissions, is inevitable in the long run.
  • In the next few decades, sea level rise will be mostly felt during acute events, such as during high tides or large storms, or a combination of the two. This will, unfortunately, cause my friends in Puget Sound to attribute their flooded living rooms to unusually high tides or large storms, but not to rising sea levels.

To examine flooding in Puget Sound under various levels of sea level rise, you can surf a map and toggle the level of sea level rise at this interactive website.