Crow Fritters

"Try to imagine half the numbers of commercial passenger flights in 2025 as today, or half the numbers of gas-powered engines. Half the numbers of WalMart SuperStores bringing full cargo ships from Shenzhen to Houston."

It is always painful to admit you were wrong, especially about something that has taken on a lot of significance in your life and you have been repeating for decades. I have that sense of contrition now as I look back on the past week and the realization that came from it.

Can one get an epiphany from YouTube? I guess so.

From Tuesday to Thursday my astral body was 3000 miles away, in the auditorium of Chalmers University in Gotebörg, while my wetware remained motionless, jacked into my laptop; tractor-beamed to an ISP tower at my rural county seat, 40 miles away. The astral body wanted to occasionally cruise the hall to one of the four other seminar rooms where important papers were being delivered but the webcast confined it to the plenary hall. The lump of flesh mostly wanted bathroom breaks and sandwiches.

What had me so enthralled was the First International Conference on Negative CO2 Emissions with 11 keynote speakers, 150 powerpoint presentations, 231 abstracts and 30 poster presentations.

The plenary hall called RunAn (Run an’ what? Hide?) had been transformed into an Emergency Planetary Care ward and the patient was dying. More than 250 of the world’s leading scientists — flying or ferrying in from 30 countries — leaned forward in their seats in upper gallery of the operating theater and exchanged banter with the surgeons reading the beeping monitors and pacing around the gurney. There was even a machine that goes ping!

Some of these surgeons were the very same ones that had created the need for the emergency measures now being mustered. They had labored for decades on committees of the IPCC, trying to get across to politicians too busy with the minutiae of realpolitik the seriousness of setting hard decarbonization targets, first at Kyoto, then Copenhagen, then Paris, and had failed repeatedly. All that was left to do now was either (a) bend over and kiss your posterior goodbye; or (b) bend the curve.

The IPCC Fifth Assessment Report quantified budgets for the 1.5ºC and 2ºC Paris targets at about 200 and 800 billion tons (gigaton or Gt )of CO2. With unchanged present emissions at about 40 Gt CO2/year, the 1.5 target will be passed in 3 to 5 years and 2 degrees within 20 years.We must bend the curve away from adding carbon to the atmosphere each year — currently a concave curve pointing up — to subtracting carbon — a convex curve peaking out and trending down. To have a realistic chance of averting disaster, we need to reach an 11 percent decline rate per annum from 2036 (preventing catastrophic climate change above 2 degrees) or better, a 20 percent decline slope from 2037 (limiting ourselves to dangerous climate change at around 1.5 degrees).

This type of curve will not be easily achieved. An 11 percent decline slope is the inverse of doubling your fossil economy every 7 years — so, halving every 7 years. Try to imagine half the numbers of commercial passenger flights in 2025 as today, or half the numbers of gas-powered engines. Half the numbers of WalMart SuperStores bringing full cargo ships from Shenzhen to Houston. Then halve that by 2032 and again by 2039. You get the picture. Phasing out the worst fossil fuels in favor of the less evil heritage fuels (sunlight, wind, firewood), will not bring carbon back into the safety zone fast enough.

The IPCC got weak knees just thinking about that so its Working Group 3 bent the curve back up a bit. The revised recommendation offered last December at COP-23 in Bonn gave more attractive narratives to policymakers — really just modest tweaks to business as usual.

The IPCC emission scenarios that meet the global two-degree target require overshooting the carbon budget at first and then removing the excess carbon with large “negative emissions,” capable of withdrawing on the order of 400‑800 GtCO2, or half-again more than humans emit.

So it came to be that delegates to UN climate conference have signed up for “negative emissions technologies” that will be sprinkled around the planet like fairy dust to reclaim over the long term the fossil emissions we are allowing ourselves in the short term (and indeed, that we, the taxpayers, are still subsidizing delivery of to the tune of 5 to 6 trillion dollars per year).

But there I go again. Calling NET “fairy dust” is what I have been doing since Copenhagen, even while extolling the virtues of biochar and carbon farming as The Great Sequestrators.

There was plenty of praise from the surgical gallery for biochar and carbon farming, for sure, but what knocked me back with a Spell of Contrition were presentations by experts on Direct Air Capture (DAC), Biomass Energy with Carbon Capture and Storage (BECCS) and Enhanced Weathering.

For years I have been calling BECCS snake oil because I imagined it just a rebranding of “clean coal” — an impossible plan to switch the world from fossil energy to biomass and continue business as usual. Carbon capture is not a heavy lift, scrubbers have been doing that for decades and the new technologies are vastly better at it. The bugaboo has always been storage because, placed in geological tombs like old coal-mines or fracked wells, carbon gas has a nasty habit of getting out — about 10 percent leakage per decade. Dumped into the ocean, which has been the main plan since the idea first appeared, it would become carbonic acid and worsen the acidification problem — now the worst it has been in a million years — destroying whatever remaining corals and crustaceans are not already dead from heat stroke.

The same kind of problem besets DAC, which scrubs the atmosphere of carbon the way a tree does, only with electric fans, stainless steel and aluminum instead of sunlight, cellulose and phloem. Also, unlike BECCS, DAC doesn’t produce its own power. To get the solvent to give up its CO2, you need copious heat. To capture a million tons of CO2 per year (one 40,000th of present net annual emissions) 300 to 500 MW are required — equal to a very large coal steam plant or several hundred wind turbines.

Among the many takeaways from the conference however, was that science never sleeps. BECCS and DAC are making major improvements. Our friend Hans-Peter Schmidt of the Ithaka Institute was there to talk about PyCCS; a tweak to BECCS where the carbon would be stored as pyrolysates, either biochar in the soil or replacements for plastics composites and aggregates in cement and asphalt. Construction aggregates alone were 53 gigatonnes in 2017, up from 37 in 2010. That’s enough to build a sidewalk around the equator 5000 times. Replacing any amount over 70% of that sand and gravel with biochar (say, from municipal biosolids or landfill carbon) would more than offset current anthropogenic emissions and take us into drawdown territory. Every additional square foot of pavement or building poured at that point would be drawing legacy emissions out of the atmosphere. You could take a century’s worth out every decade if you could just bring yourself to stop adding more.

At the current stage of commercial development, many DAC operators, such as those in Sweden, plan to sell the harvested CO2 instead of storing it. It could go into carbonated beverages, for instance. To my jaundiced eye, this is catch-and-release to the atmosphere, rather than drawdown. Until the storage problem has a commercially viable, antifragile way of sequestering carbon, DAC cannot be considered a solution.

The solution to the power hunger and high price of DAC, keynoter Jennifer Wilcox told us, was to stop trying to get CO2 to 95% purity. Just take a moment to consider how much energy it takes to concentrate CO2 from 400 parts per million (the air) to 950,000 parts per million. She pointed to the idea of Klaus Lackner at Arizona State University’s Center for Negative Carbon Emissions to take CO2 at low concentrations and feed algae, thereby producing biomass (energy feedstocks and superfoods) and hydrogen (for portable fuels).

The final keynote, by Phil Renforth at the Carbonate Systems Engineering Group at Cardiff University, looked at the ways rocks take carbon out of the atmosphere by weathering. For a third the cost of a ton of biochar he showed how we could not only build better soil fertility and improve success rates for reforestation, but avoid acidifying the oceans. In fact, we could be reversing ocean acidification by creating soluble bicarbonate biological fertilizers.

Sure, there were a number of talks that were really just desperate attempts to return a poorly designed, rapacious consumer economy to its perceived former glory, future generations be damned. I’d list Columbia professor James Hansen’s opening keynote in that category, and watched with sorrow and pity as he made his too-familiar impassioned plea to give nukes a chance.

Hansen sounded like an old lefty reciting the mantra, “The Workers, United, Will Never Be Defeated!” I will happily admit I may have been wrong about DAC but I am not wrong about nukes.

So there it is. I went from being skeptical about geoengineering technologies like BECCS and DAC to seeing how they might actually work to restore health to coral reefs and forests beset by rapid climate change. Moreover, they could perform those miracles in ways that take account of humanity’s need to switch from overpopulated consumerist economies to something more attuned to Gaian rhythms and flows. And they could bring those in at scale, at low cost, or even negative cost, meaning government programs to force them onto the market would be irrelevant and unnecessary. Sounds too good to be true. 

Yet there are college kids signing up for courses, nerdy tinkers in dimly-lit garages, and lab-rat inventors cashing in their savings bonds to pursue these dreams. The one thing we have going for us, we naked apes, is we are clever little buggers.