We Need to Talk About Carbon Removal
Carbon dioxide removal — removing carbon dioxide (CO2) from the atmosphere — is one of the most important yet under-resourced parts of our climate solutions portfolio. It comes down to two important facts:
- CO2 has a lifetime in the atmosphere of decades up to thousands of years [1]
- Humans add 40 billion metric tons (40 gigatons) of CO2 to the atmosphere every year [2][3]
Even if we stopped emitting CO2 today, we would still have an atmospheric carbon surplus to clean up.
To give you an idea of scale, one metric ton of CO2 can be visualized as a sphere 33 feet across. The folks at Carbon Visuals have illustrated what one year of New York City’s CO2 emissions (.05 gigatons, 0.1% of total global emissions) looks like in the form of these spheres.
If I asked you to name a few ways that we are combating climate change today, you might say something like: solar and wind energy, electric vehicles, reducing food waste, eating less meat. All of these go under the umbrella of “reducing our emissions into the atmosphere”. But we also need to clean up what’s already there. It took me countless hours to wrap my head around carbon dioxide removal (CDR) and its solutions ecosystem, so here is the 101 I wish I had from the start.
How much CO2 is out there, where is it from, and where does it go?
Since the pre-industrial period, the concentration of atmospheric CO2 has risen from 280 to 408 parts per million (ppm) today. That means that today, for every 1 million air molecules, 408 of those molecules are CO2. CO2 concentrations have not been this high for millions of years.
Between 1750 and 2011, cumulative emissions totaled:
- 1376 ± 110 gigatons (Gt) of CO2 from the combustion of fossil fuels (coal, gas, oil, gas flaring) and cement production [4]
- 660 ± 294 Gt CO2 from land use change (i.e. developing land for human use), mainly from deforestation [4]
40% of these emissions have remained in the atmosphere. Natural carbon sinks that absorb atmospheric carbon — namely the ocean and land (soil and vegetation) — have evenly absorbed the other 60% of the anthropogenic (human-created) CO2. [5]
You may have heard that 2 degrees Celsius is the maximum temperature increase from pre-industrial times that is allowed in order to avoid the worst of climate change. This 2°C increase doesn’t just mean sea level rising or saying goodbye to polar bears — it also means global instability, climate migration, increased extreme weather events, and resource scarcity, all requiring high levels of adaptation.
The Intergovernmental Panel on Climate Change (IPCC), the United Nations body that reports on climate change, reported that in order to avoid that 2°C increase, cumulative CO2 emissions from all anthropogenic sources must remain below 3650 GtCO2 (1000 Gt of carbon). [6] This 3650 Gt of CO2 has been called our carbon budget. Unfortunately, as mentioned above, we already emitted more than half of this allotted budget by 2011, so we must remove atmospheric CO2.
Further, IPCC scenarios that are “likely” to maintain warming at below 2°C are characterized by a 40–70% reduction in greenhouse gas emissions by 2050, relative to 2010 levels, and emissions levels near or below zero by 2100. [7] Note that in order to reverse climate change, we need to be even more aggressive.
What usually happens to CO2 in the atmosphere?
For a very short 4-minute explainer, this video is very good at explaining natural carbon cycles and our atmospheric carbon surplus.
Carbon has natural sinks: the oceans, soil, and vegetation. However, these sinks cannot adapt fast enough to absorb the unnatural amount of carbon we’re releasing — by burning fossil fuels, we’ve taken carbon that would have naturally been sequestered (stored) essentially forever, and released it in a short span of time. Let’s take a closer look at these sinks:
Soil
With 2500 petagrams (1 Pg = 1 Gt)* of carbon in the Earth’s top 1 meter, soil contains more carbon than the atmosphere and plants combined. Unfortunately, soil can release stored carbon when it’s disturbed, and almost half of land that had native vegetation has been converted to croplands, pastures, and rangelands. Through both land use and soil cultivation, about 214 ± 67 Pg of carbon have been released to the atmosphere. [8] This also impacts food, as we’ve stripped agricultural soil of carbon and nutrients. Further, terrestrial ecosystems can potentially become saturated and turn from sink to source. [9] It’s worth noting that increased warming is expected to melt permafrost, a frozen layer of soil, rock, or sediment in polar regions, releasing immense amounts of CO2 and methane and contributing to a positive feedback loop with global warming.
Vegetation
Plants absorb CO2 through photosynthesis, and naturally, carbon is returned as CO2 or methane to the atmosphere through respiration or decomposition (rotting or decay). Unfortunately, deforestation and forest fires release years of accumulated carbon back to the atmosphere. For agriculture, we have cleared dense forests for farmland, which sequesters less carbon. A recent study showed that due to deforestation and disturbance, tropical forests, which sequester a third of land carbon, are becoming a carbon source of 1.6 ± .3 GtCO2/yr (~4% total annual global emissions). [10] The relationship between agriculture and vegetation plays a major role here, as feeding the world is extremely important.
It’s worth discussing blue carbon, carbon stored in coastal ecosystems like mangroves, salt marshes, and sea grasses. These habitats have been shown to sequester carbon faster and store more carbon per acre than tropical forests, mostly because a lot of the carbon is stored in the soil and not in the plant matter above ground. [11] Though these forests are smaller than terrestrial forests, degradation of blue carbon has been estimated to account for 3–19% of carbon emissions from deforestation. [12] Cumulative losses of seagrasses, salt marshes, and mangroves are estimated at 29%, 35%+, and 67%+ respectively. [13]
Oceans
The uptake of anthropogenic CO2 by oceans is generally influenced by the concentrations of CO2 both in the atmosphere and ocean, as well as surface mixing (impacted by wind, currents, and temperature). The ocean has two main CO2 pumps: 1) The solubility pump, by which CO2 is taken up in colder water at high latitudes, sinks to the deep ocean for several hundred years, and then resurfaces where water is warm (e.g. the tropics) where CO2 is less soluble and released back to the atmosphere. 2) The biological pump, by which phytoplankton absorb CO2 via photosynthesis, and sequester a small amount of carbon when they die and sink to the deep ocean, where they are buried in sediment. Side note: oil is formed from marine life that died and was buried in sediments before fully decaying!
You might think “Great! Let’s let the oceans absorb CO2.” Well, not so fast… When CO2 is absorbed in the ocean, carbonic acid is formed, acidifying the ocean. In a more acidic ocean, shell-building animals like coral and shellfish have a harder time building their shells. Worse, carbonic acid may also directly dissolve these animals’ shells. It’s also worth noting that global warming warms the oceans and in turn decreases water’s ability to hold CO2.
How can we remove CO2 from the air?
Fortunately, people all over the world are working on CDR — the field appears larger every time I dig deeper. It’s an exciting time, with momentum really building over the past few years.
I should note that this list is not exhaustive and there is ongoing work in many areas. Broadly, solutions can be broken down into three categories:
- Biological Approach: Enhance natural removal pathways
- Engineered Approach: Remove CO2 from the air using engineered solutions
- Hybrid Approach: Combine elements of both engineered and biological approaches
Biological Approach
There are many options to enhancing natural carbon sinks:
Plant more trees (afforestation/reforestation)
(potential to remove 4–28 GtCO2/yr)** — You know this one. Just plant more trees where they used to be (reforestation) or in new places (afforestation)! Some folks, like those at Propagate Ventures, are working on incentivizing farmers to integrate trees into their practices (agroforestry). Others, like OpenForests, are working to provide better tools to manage land and forests.
Regenerative agriculture
(potential to remove 4.8 GtCO2 equivalent/yr) — I am honestly fascinated now with soil, which has been widely degraded through industrial agriculture and its reliance on synthetic fertilizers and pesticides. There is currently a growing movement called regenerative agriculture, a set of practices used to improve soil health, both restoring carbon content and the vast microbial life that makes soil healthy. Among other benefits, crops become healthier and more nutritious, water and nutrients are retained better, and erosion is reduced. Practices include: reduce soil disturbance (e.g. tilling), diversify soil biota by rotating crops, and plant cover crops to cover the soil and keep something living in the soil year-round. Carbon can potentially be stored in soils for millennia, but can also be quickly released, depending on how soil is managed, as well as other factors like climate conditions, soil type, and drainage. [14]
Organic farming was one giant step in the right direction, away from synthetic pesticides and fertilizers. Regenerative agriculture goes one step further, to rejuvenate the soil sustainably. Big names are getting into the movement as well. Dr. Bronner’s, Patagonia, and others have teamed up with the Rodale Institute to fill the gap they see left and create a regenerative organic certification for regenerative agriculture while advocating for better animal husbandry and farm worker rights.
Biochar
(potential to remove 1.8–3.3 GtCO2 equivalent/yr) — Another way to return carbon back to soil is through biochar, a stable form of solid carbon formed when biomass is heated to a high temperature in an oxygen-limited environment. Biochar can be produced from woody material or agricultural waste that would otherwise decompose and release carbon back to the atmosphere. Since biochar production blends engineering with plant uptake of CO2, it is considered a hybrid approach to CDR. The real magic of biochar is that it is extremely porous, and when crushed and put into soil, it can increase nutrient and water retention and serve as a home for healthy microbes. The creation of biochar can also produce usable energy and heat. Because of its porosity it has also been considered for other uses like toxin remediation, and water filtration in place of activated carbon where carbon is not typically renewably sourced. Full disclosure: When I originally published this piece, I was the product lead at a biochar company (Carbo Culture) in California creating high-carbon biochar from walnut shell waste.
Enhanced weathering
(potential to remove 0.7–3.7 GtCO2/yr) — Certain rocks*** that have available metal oxides like calcium or magnesium, react with CO2 to form solid carbonates (calcium carbonate, magnesium carbonate, respectively). Researchers are exploring the possibility of taking this rock and crushing it to increase its surface area, allowing it to speed up this natural mineralization process, which is typically a very slow part of the carbon cycle. Natural rock weathering removes approximately 1 billion tons of CO2 annually. [15] These rocks are abundant far below the Earth’s surface, and would need to be mined. Fortunately, some of this rock is actually already mined during other mining operations, and left as mine waste. These rocks have also shown fertilizing capabilities, further providing a potential benefit to agriculture. One company, Plant Nutrition Technologies Inc., is capitalizing on this concept and taking mine waste, crushing it, and producing the rock dust for use as fertilizer.
Oceans
There are also R&D efforts in sequestering carbon using the ocean’s ecosystems. There are groups working on marine permaculture, creating giant kelp forests that soak up carbon and sink to the bottom of the ocean when they die, sequestering the carbon. There is also research around promoting phytoplankton growth by seeding the ocean with iron or upwelling nutrients from the deep ocean. The idea is that a portion of these phytoplankton will sink to the bottom of the ocean and sequester the carbon. There is still ongoing research on the effects of these efforts on marine ecosystems.
Engineered Approach
Direct air capture
(potential to remove 2–5 GtCO2/yr)**: There are a few companies working on pulling CO2 directly out of ambient air, notably Climeworks in Switzerland and Carbon Engineering in Canada. This method involves giant machines that pull in air, where CO2-”grabbing” chemicals are dissolved in water or used with solid materials, and then the CO2 is released for capture through heating. A challenge here, besides scale, is just that there’s so much carbon out there — .04% of air is CO2. And to yield negative emissions, the energy used would be powered mostly by zero-carbon energy sources. This can be a costly process, though Carbon Engineering recently showed CO2 can be captured at as low as $100/ton in the next five or so years.
Carbon capture from power generation and industrial production
This is the classic and most common way to capture carbon thus far. CO2 in flue (exhaust) gas can be captured at a coal or natural gas plant or other industrial facility (e.g. fertilizer production, steel and paper mills). However, these processes are not carbon negative because they’re still taking net carbon from underground. One added advantage over direct air capture is that the CO2 is more concentrated (15%+) in a waste stream than in ambient air. [16] The process is expensive, requiring a technology where CO2 binds to amines which are then heated to a high temperature (120–150°C) to release the CO2, taking up to 30% of the plant’s own energy to separate the flue gas. [17] There are some folks who are working on making this process more sustainable, notably Mosaic Materials, which makes this process less energy-intensive.
Bioenergy with carbon capture and storage (BECCS)
(potential to remove 2–18 GtCO2/yr) — BECCS involves growing trees or bioenergy crops like grasses or oilseeds, using the biomass as fuel for power plants, then capturing the emissions and sequestering the CO2 underground. In this manner, BECCS is a hybrid approach to CDR. BECCS has the potential to generate an estimated 14–20% of global primary energy supply. [18] One start-up, Charm Industrial, is applying the BECCS model to produce industrial hydrogen, which can be used for ammonia production, transport, and other industrial processes. BECCS requires substantial land use at scale, creating a potential barrier due to its competition with agriculture and other land use. [19] According to the Global CCS Institute, there are currently only two large-scale BECCS facilities either planned or in operation worldwide.
The interactive Third Way carbon capture projects map and the Global CCS Institute project database do a fantastic job of showing where these projects are.
What happens to captured CO2?
The landscape for use and storage of captured CO2 is evolving, but one constant remains: with all of these solutions, the goal is to store carbon permanently.
Store as-is
Captured CO2 can be injected and sequestered deep in geological formations. There’s an estimated 5,000+ GtCO2 of geological storage capacity, though not all of it is viable for actual storage. [19]
Mineralize the CO2 and store as a solid
Captured CO2 can be reacted with certain metal oxides to form carbonates, solids such as magnesium carbonate or calcium carbonate. This form of storage is attractive because there is less potential long-term leakage than there is with gas storage. Climeworks is one partner of a project in Iceland called CarbFix2 that stores captured CO2 in basalt, which reacts with the CO2 and forms carbonates within a couple of years, storing it permanently.
(Edit Feb. 2021) Since this article’s original publication, Climeworks has started a program by which individuals like you or me can pay for them to pull CO2 out of the air on a subscription basis. I’ve been signed up for a couple of years now.
Recycle it into a product
Many companies are reframing CO2 as a resource, rather than waste, creating what is called the new carbon economy. They’re making products out of CO2 including: plastics, synthetic fuels, concrete, carbon composites, and other carbon-based materials. Let’s look at plastics, synthetic fuels, and concrete here:
Plastics/synthetic fuel: Through conversion technologies, bonds in water and CO2 can be rearranged to form new molecules. These processes enable companies like Berkeley-based Twelve (fka Opus 12) and Carbon Engineering to take captured CO2 and turn them into synthetic fuels, plastics, and other products that would otherwise have used petroleum as a feedstock.
Cement: Cement production actually accounts for about 5% of all global carbon emissions. [20] It’s mind-blowing until you look around you… it’s likely you can identify concrete near you right now. The typical process to create Portland cement (which is mixed with sand and gravel to make concrete) releases CO2 in two main ways: by burning fossil fuels to heat and break down limestone, and through the resulting release of CO2 from the limestone’s decomposition. For every ton of Portland cement produced, nearly a ton of CO2 is released. [21] Notable companies, CarbonCure Technologies, Solidia Technologies, and Carbicrete, among others, are changing the process through which cement is made. Solidia replaces a portion of limestone with a low-carbon mineral that emits less CO2 in cement production, can produce their cement with less energy, and cures their concrete with CO2 instead of water. Carbicrete uses industrial waste steel slag instead of cement as their concrete’s primary binder, and injects CO2 into the wet concrete to strengthen it. CarbonCure injects CO2 into wet concrete as it’s mixed, turning CO2 into calcium carbonate (limestone), and reducing the amount of cement needed.
Note that the process to create cement, where calcium carbonate is broken down into calcium oxide and CO2, is reversed as cement deteriorates (lime reacts with water and atmospheric CO2 to make calcium carbonate again). One study has estimated that this process has meant the absorption of 4.5 billion tons of CO2 taken up by cement since 1930, actually offsetting some of the emissions from cement production. [22]
Use as-is
There are currently a handful of uses for CO2 today, including beer production, stunning pigs before slaughter, and preserving packaged products. Ironically, the largest use for CO2 today is for enhanced oil recovery by which supercritical CO2 is injected into an oil reservoir, pushing out the last bits of hard-to-reach oil. 70 million metric tons of CO2 a year are used for this purpose in the US alone, but most of the CO2 used for this today is mined from CO2 reservoirs underground. [23]
Challenges
Cleaning up carbon at the scale that matters is a monumental but achievable task. Much of carbon tech is at the pilot or R&D phase, and natural solutions also have their own challenges. We need an “all of the above” “all hands on deck” kind of portfolio for some serious catch-up. Let’s talk about some important challenges and who’s tackling them.
Market demand
Companies are increasingly seeking to offset their own emissions, either by government mandate or simply because it’s part of their own business strategy (Lyft comes to mind). There’s a potential opportunity to increase the market for carbon removal. As more options become available, an individual like you or me can also participate in the carbon market by buying carbon-based products or funding carbon projects! There are three markets that I want to frame: captured carbon, captured carbon-based end products, and natural carbon drawdown.
- Captured carbon: The price of bulk CO2 typically has fallen to around $20 or less, so the return for selling that carbon has to justify the cost of capture. The current CO2 market is supplied mostly from natural CO2 reservoirs or as a by-product from industrial sources, so new sources would have to be competitive.
- Captured carbon end products: Captured carbon based products (e.g. plastics, fuels) need to compete on the market against cheap conventional options.
- Natural carbon drawdown: Enhancing natural sinks, like vegetation or soils, also requires demand. On the soil health side, there is the dual benefit that keeping carbon in the ground also happens to benefit agriculture. But it can be risky for farmers to take that leap. Enter Nori, a company creating a carbon marketplace with a market-driven carbon price, so as more participate, the value of a carbon credit will increase. Their blockchain-based market seeks to address issues with conventional greenhouse gas marketplaces, and enables companies to pay farmers directly for carbon to be sequestered, while making the CDR transaction transparent and verifiable. Even more broadly, there are a number of blockchain groups working to create markets based in natural capital like trees. One organization, Generation Blue, has offered a coin by which you can sponsor a new mangrove tree in Myanmar, while being able to hold some percentage of liquidity.
Governments
The public sector has a major role to play to incentivize carbon drawdown. We saw this with solar and renewable energy — in the US, government levers at the federal and state level helped bring solar to the masses by making it more affordable. Governments can use mechanisms like tax credits, regulations, R&D funding, to push in the right direction. You’ve probably heard about carbon taxes and cap-and-trade systems, which are slowly starting to pick up worldwide, as methods to reduce emissions.
But here I’m going to write about developments specific to removing atmospheric carbon. The 45Q extension, called the FUTURE Act, was the first time a federal price was put on carbon in the US. It does a number of things to incentivize carbon capture, utilization, and storage including:
- Increase the tax credit given for sequestering captured carbon underground from $20/ton to $50/ton over the next 10 years.
- Introduce a new $35/ton credit for putting captured emissions into a product.
- Increase the tax credit for pumping CO2 underground for enhanced oil recovery from $10/ton to $35/ton. These credits can be claimed for 12 years, incentivizing projects with a longer term payout. Carbon180 does the math: “A large-scale coal power plant capturing 90% of its 5 million tons a year would eke out a lifetime value of $1.89 to $2.7 billion.”
The extension also makes carbon capture from the atmosphere eligible for tax credits for the first time ever. In California, and hopefully eventually other state governments, there will be further incentives like the Low Carbon Fuel Standard*** in California. And earlier this year, a bipartisan group of senators introduced a bill called the USE IT Act to further support direct air capture and carbon capture, use, and storage.
Governments can incentivize carbon drawdown on the natural side as well. In my agricultural state of California, SB-5 was passed, opening funding for better soil and carbon restoration practices.
Funding
Carbon removal is an emerging space, and fundamental knowledge is necessary for investors to put money into them. There are really good signals in the market that funding and support is coming around:
- Y Combinator, the legendary incubator, which called for carbon tech startups earlier this year
- Packard Foundation, which is opening up a major fund around bioenergy and CDR
- Carbontech Labs, a new accelerator for carbon tech run by Carbon180
- The XPrize competition, promising $20 million to the winner in 2020
- Cyclotron Road, a fellowship for entrepreneurial scientists and their startups, currently including Opus 12 (now Twelve) and Mosaic Materials.
- Even NASA is offering a prize for ways to make products made out of CO2, for future use on Mars
This is just the start as investors start seeing carbon as a major opportunity — from new products, waste-to-resource, and better agriculture, there are massive opportunities in this space that also make good business.
System sustainability
Some solutions compete with other resources like agricultural land, and require inputs like water and energy. It’s important that the model for carbon removal takes into account overall sustainability, and scales in a way that is better for land, food, ecosystems, social equality, and biodiversity. If we’re going to build it, we should build it right and just.
R&D and Academia
There is so much more work to be done in developing ways to draw down CO2. In addition to companies and NGOs, universities around the world are breaking ground in these areas, some of whom are part of the The New Carbon Economy Consortium. One day, I hope carbon removal is a core part of a college education the way renewable energy was for me when I studied environmental engineering.
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What can I do?
At the very least, talk about carbon removal! And if you can, get involved and take action. Support legislation for carbon removal, do your own research, maybe even enter the CDR field! You can also reach out to me. I’d love to hear your questions and feedback, or talk to you or your organization about CDR. My goal is to start a dialogue and have others join me and work together.
Other resources
- One of the best books to read is Project Drawdown, an extremely comprehensive look at the most substantial ways to solve climate change.
- I’ve also learned a ton by listening to the fun Reversing Climate Change podcast run by Nori, where really interesting folks in the space are interviewed about their work in reversing climate change. (Edit Feb. 2021) I recently joined the podcast as a guest to talk climate career pivots and my recent article Chasing a Job With Purpose.
- Carbon 180 (formerly The Center for Carbon Removal) is one of the most engaged groups in the carbon community. They’re focused on both policy and industry, and are generally a fantastic resource.
- Air Miners (previously ManyLabs) is a growing digital CDR community based out of San Francisco, a great place to connect with others and get plugged in. (edit: July 2020) In early 2020, they hosted the very first carbon negative CDR conference. Air Miners also curates a really comprehensive and evolving list CDR companies and projects, and has a great CDR 101 resource (full disclosure: this article is on the recommended reading list).
About me: I’m an environmental engineer (Harvard ’14) and product manager who spends a lot of time talking to people about CDR, environmental justice, and agriculture in real life as well as on Twitter. Currently, I’m working on reversing CO2 emissions at Twelve (fka Opus 12), and spend a lot of time with the broader CDR community. Lastly, I’d like to say I’m grateful for all the folks who helped me edit this article!
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References
I invite you to look further into my source documents, ask questions, and learn more. Here are my rough citations, not adhering to particular rules.
[1] IPCC Fifth Assessment Report, WGI: The Physical Science Basis, Chapter 6, Pg. 472 (note that the IPCC only creates a report every 5 or so years)
[2] Global Carbon Budget 2017, Global Carbon Project, Slide 40
[3] This number increases to ~50 Gt CO2 equivalent when accounting for other greenhouse gases such as methane and nitrous oxide. Citation: Creating a Sustainable Future, World Resources Institute Report 2013–2014, Pg. 85
[4] IPCC Fifth Assessment Report, WGI: The Physical Science Basis, Chapter 6, Pg. 486 (Note the source data was in petagrams of carbon*)
[5] IPCC Climate Change 2014: Synthesis Report, Pg. 45
[6] IPCC Climate Change 2014: Synthesis Report, Pg. 63
[7] IPCC Climate Change 2014 Synthesis Report, Pg. 82
[8] Global Sequestration Potential of Increased Organic Carbon in Cropland Soils, Zomer et al., 2017.
[10] Tropical forests are a net carbon source based on aboveground measurements of gain and loss, Baccini et al., 2017 (Source data was 425.2 ± 92.0 Tg C, and I converted to GtCO2 for uniformity).
[11] “Coastal Blue Carbon”, NOAA Fisheries
[12] “Blue Carbon”, The Blue Carbon Initiative
[14] “Carbon Sequestration in Soils”, Ecological Society of America, 2012.
[15] Project Drawdown, Paul Hawken, 2017. Pg. 177
[17] ”New material captures carbon at half the energy cost”, Berkeley News, 2015.
[19] Emissions Gap Report 2017, A UN Environment Synthesis Report, pg. 62
[21] “Emissions from the Cement Industry”, Earth Institute, Columbia University, 2012.
[22] Cement materials are an overlooked and substantial carbon ‘sink’, Science Daily, 2016.
[23] “The seemingly illogical reason Europe is running low on carbon dioxide… and beer”, Quartz, 2018.
*Quantities of carbon are typically in terms of grams, whereas CO2 are typically in tons, where 1 PgC = 1 GtC, and when carbon is in the air as CO2, it is about 3.67x the quantity of carbon due to atomic weight. The atomic weight of carbon and CO2 respectively are 12 atomic mass units (amu) and 44 amu, so one ton of carbon is approximately 44/12, or 3.67 tons of CO2.
** All estimates of potential removal are from the Emissions Gap Report 2017, A UN Environment Synthesis Report, Chapter 7
*** I published this piece when Carbon180 was transitioning from The Center for Carbon Removal and migrating their blog in the move. I’ll update these links when they are live again.
