Farming Feeds Billions But Climate Impacts Need Fixing
Many of us hold romantic ideas about farming. We imagine wise stewards of the land who preserve soil for future generations. We think of gentle nurturers of livestock who ruefully cull it for food for the world. We think of farms as bucolic and climate friendly places.
Most of that is utter nonsense.
To start with, about 10% of total greenhouse gas emissions come from agriculture, which is why changing how we do it is on the short list of climate actions that will work.
Agriculture and animal husbandry have been transformed in the past 100 years, and especially since the start of the Green Revolution in the 1940s in Mexico. Norman Borlaug developed new disease resistance high-yield varieties of wheat which combined with new mechanized agricultural technologies to massively increase agricultural productivity. Mexico transformed from importing half of its grain to being an exporter.
Specialized automation has been an ongoing source of efficiencies and frustrations, with John Deere’s modern tractors featuring GPS, precision agricultural management technologies, stereos, air conditioners, many kilometers of wires, US$700,000 price tags and very limited ability of owners to fix them should something go wrong.
The current wave of automation is with drones. Approaching 100% of American farms now survey fields and crops with the tiny unmanned craft most of us think of as toys. Those expensive tractors as well as crop-dusting helicopters and small airplanes are being left increasingly idle as massive, 3.5 meter span, electric hexacopters carrying up to 90 kilograms of herbicides, pesticides, fungicides or fertilizer at a time apply it precisely to crops. “Farmers” spend time in their offices integrating sensor data and using laptops to plot routes for drones to follow and how much of what product to drop where.
Tractors are now electrifying as well, with multiple vendors offering battery-powered electric vehicles to displace their diesel-gulping siblings.
The trend to electrification is positive, and the use of drones is even more positive. Burning electrons instead of diesel reduces climate and health impacting emissions. Soil compaction from farm equipment reduces crop yields by 9% to 55% per studies, and drones don’t touch the soil, leading to yield increases. Precision drone spraying, per early data from a study pending publication, can reduce the amount of product sprayed by up to 50% with the same crop yields.
When people think of farms, they don’t image high-tech automation with coordination of complex sensor data feeding pathway creation for autonomous flying drones and ground equipment. The romantic image of a young farm child learning to milk a cow is equally out of touch. Dairy farms feature massive milking barns with automated milking attachments for hundreds or thousands of cows that feed into massive sterilized tanks for the product. The largest such farm, in China unsurprisingly, is the size of Portugal, has about 100,000 dairy cattle at any given point and produces 800,000 million liters of milk annually.
At one point, 95% of the population of countries like the USA were involved in agriculture, animal husbandry or agricultural product processing and distribution. Now it’s under 3%.
But it wasn’t just automation, of course. Another major part of the Green Revolution was interbreeding the plants themselves into the varieties we pluck off the shelves of grocery stores today. This has led to varieties with excellent caloric and nutritional yields that are very resistant to the most common plant diseases. A farmer from 1600 would barely recognize many or most of the plants sown and harvested today globally.
But with those high-yield, hardy varieties came monocultures. That they were resistant to many of the challenges plants faced did not mean that they were resistant to all of them. With the changes in plants came often tightly coupled changes in the chemicals we applied to crops to prevent fungi and insects from destroying them and weeds from strangling them.
Most importantly from a climate perspective is that globally there has been a massive increase in the use of ammonia-based fertilizers. Plants need nitrogen. That molecule is the most common in the air we breathe, about 78% of it. Nitrogen is 3-4% of most plants’ mass. We used to rotate crops and use clover and other nitrogen fixing plants on fallow fields, but now we just apply ammonia-based fertilizers, as ammonia is nitrogen and hydrogen.
And here’s the biggest climate problem. Ammonia-based fertilizers are made from natural gas or coal gas. Hydrogen is stripped off of the gas and combined with nitrogen from the air in a process that burns gas to create heat to turn water into steam. The carbon from the gas combines with oxygen from the air to make carbon dioxide, a greenhouse gas.
Every ton of hydrogen we create from natural gas comes with about eight tons of carbon dioxide we vent to the air. And natural gas and coal gas leak from point of extraction to point of use, producing even more climate heating.
Modern ammonia-based fertilizers are another fossil fuel, but for plants not cars.
There’s more. When we apply ammonia to fields, some of the nitrogen in the fertilizer binds with oxygen from the air to create nitrous oxides. One of those oxides is a very potent, long-lasting greenhouse gas, about 265 times more potent than carbon dioxide.
We will fix the manufacturing of ammonia with green hydrogen, eliminating that source of greenhouse gases. But we can’t change the chemical reactions that turn it into a potent greenhouse gas when we apply it to fields.
We can, however, reduce our use of it. Remember those electron-sipping, high-precision drones? While they can’t do the massive fertilizer application that occurs just after harvest, they can do the three to five additional fertilizer additions that occur during the growing season. They cut the amount of ammonia fertilizer required by up to 50%.
Is that all we can do? No. In parallel with plant genetics, there’s a great deal of innovation and commercialization of nitrogen-fixing solutions that don’t use ammonia at all. Pivot Bio’s founders spent their PhDs in agricultural genetics looking at the problem. They unravelled the nitrogen-fixing capabilities of a common soil microbe, and were trying to figure out how to insert the genes into plants. Then they had their aha moment while walking to a coffee shop.
Soil microbes that fix nitrogen are as lazy as the rest of us. They live off sugars that the plant pushes out of its roots to feed the symbiotic ecosystems in the soil in the wild. When there isn’t enough nitrogen in the soil, the microbes make it. When there is, they don’t bother, just get fat and multiply on the sugars.
So Karsten Temme and his Pivot Bio co-founder decided to just get rid of the nitrogen sensor in the microbes. They now manufacture packages of the genetically altered microbes using standard yeast-based brewing techniques that any beer maker would understand that last on shelves for years. Farmers coat seeds with it before planting, or inject it with seeds while sowing, and the microbes happily provide a lot of the nitrogen the growing plants required.
When I spoke to Temme a couple of years ago, they already had a million acres of US corn growing with their product, and were reducing fertilizer requirements by 25%. Their stretch goal is 100% for wheat, corn and rice by 2030, and if their solution doesn’t do it, there are a lot of other innovators working on the same problem globally.
Next up is low-tillage farming. Plants suck carbon out of the air and into the soil. Natural soil is a complex ecosystem that includes a lot of mushroom threads that slowly harvest carbon and lock it into long-lasting chemicals. When farmers plough the soil to break up that soil compaction problem, they destroy the sub-surface ecosystems. The carbon that was in the soil almost immediately returns to the air as carbon dioxide. The mushroom threads that were slowly drawing carbon into permanent storage are destroyed. And so, let’s change a lot of our agriculture to get rid of ploughing.
The combination of precision agriculture, agrigenetics for nitrogen fixing and low-tillage farming means we can eliminate carbon emissions from modern farming in the coming decades.
But that’s for industrial farming. Small hold farmers, romantic as they might be, aren’t well enough capitalized by themselves. In Europe, they form co-ops to buy agricultural equipment that they can’t afford individually, but still have to run it inefficiently on small fields, a compromise forced by culture, regulation and an unwillingness to change.
It’s relatively easy to change the 600-800 biggest industrial agricultural giants globally. They are corporations with Boards and stakeholders, and respond rationally to carrots and sticks. There are a limited number of them. It’s much harder to change the approaches of millions of small hold farmers, but possible. They need to compete and survive and they must embrace the advances or differentiate themselves with ‘all-natural’ approaches.
It’s the last segment of farmers we also have to deal with, subsistence farmers. These are not the modern affluent hobby farmers who use their trust funds to grow many things that they consume and barter with slow food networks. These are the global deeply impoverished, the billion or so people living hand to mouth on the land. These are the calorie strippers, taking everything that they can from the land in a desperate attempt to keep their families fed and sheltered. These are the people with little education, no capital and little technology.
There is absolutely nothing romantic about the lives of these billion deeply poor people scraping food from semi-arable land or herding scrawny goats over rocky hills. They are merely the human beings we have still left behind. We need to assist them and their children to move to urban areas as much as possible. We need to free the land they are scraping bare to be used more productively, whether that’s adding the most fertile portions to larger farms, putting wind or solar farms on it, planting trees on it or simply letting it rewild by itself.
Farming is not romantic. It’s a complex, sophisticated business that’s absolutely essential to feeding the billions of us who live and dream on this planet. And it’s a big climate problem that we have solutions for. That’s why fixing it is on the short list of climate actions that will work.
As a reminder, here’s the short list of climate actions that will work:
- Electrify everything
- Overbuild renewable generation
- Build continent-scale electrical grids and markets
- Build pumped hydro and other storage
- Plant a lot of trees
- Change agricultural practices
- Fix concrete, steel and industrial processes
- Price carbon aggressively
- Shut down coal and gas generation aggressively
- Stop financing and subsidies for fossil fuel
- Eliminate HFCs in refrigeration
- Ignore distractions
- Pay attention to motivations