We’re Eating This Planet to Death - Africa Green Magazine

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We’re Eating This Planet to Death

A new IPCC report is clear: If we can’t figure out how to feed our species more sustainably, climate change will accelerate and make it harder to grow food.

THE UN'S INTERGOVERNMENTAL Panel on Climate Change released a dire report Thursday arguing that humanity can’t truly fight climate change without addressing the land problem—habitat degradation, deforestation, and soils beat to hell by agriculture. We now use nearly three-quarters of the world’s ice-free surface and waste a quarter of the food we produce, all while the global food system contributes up to 37 percent of our greenhouse gas emissions.

In short, we have to fundamentally rethink how we grow crops and raise livestock. There’s no panacea, and every potential fix is fraught with maddening complications. But if we can’t figure out how to feed our species in a more sustainable way, climate change will continue to accelerate, making it all the more difficult to grow enough food. Food systems will collapse, and people will die.

The fundamental problem is that we have finite arable land and an exploding population. And trends that are positive from a social perspective, such as the ascent of the poor into the middle class in booming economies like China’s, end up ratcheting up the demand for meat even more.
So let’s start with meat. Raising livestock for slaughter is, of course, not particularly good for the planet. Animals demand lots of food and water: A single cow might consume 11,000 gallons of water a year. And that cow burps up methane, an extremely potent greenhouse gas.
In labs around the world, researchers are working on an alternative, by trying to get meat cells to grow in petri dishes. Using vats controlled for temperature, oxygen content, and more, they are replicating the conditions inside a cow without the methane side effects. And that, they promise, will be far better for the planet than growing beef out in a field.

But the promise of a lab-grown meat that replaces livestock in a significant manner is still far off. No one has a fully operational facility churning out the stuff. That means there also isn’t much data to show how, exactly, it stacks up against factory farming. “If you're growing cells, you have to provide them with oxygen and heat and food and clean their waste and all the rest of it,” says Alison Van Eenennaam, an animal geneticist at the UC Davis. “That won't come free. A cow is keeping its body temperature and doing its own waste removal.”

Labs and cows also release different greenhouse gases. To grow meat in the lab, you need electricity, which means CO2 emissions. That CO2 lingers in the atmosphere for thousands of years, whereas the methane released by cows lasts more like 12 years. Powering future lab-grown meat facilities with renewables will be essential to improving the climate-wrecking profile of meat.

But cows are not just raised for their meat. India, for example, has 300 million cattle, three times as many as the US, but most Indians don’t eat beef. What they do use is the dairy; in fact, they are the biggest producers of dairy on the planet. “I don't have a simple solution for what you do with a country that has the most cattle on Earth and has the lowest beef consumption,” says Van Eenennaam. “Just saying eat less beef doesn't take care of that problem.”
There are also regional differences. A cow in one country is not fungible with a cow in another. Raising cows in Latin America or sub-Saharan Africa produces twice the emissions of cattle kept in Europe or the US, because animals in the latter countries are fed more nutritious food and are more likely to be vaccinated and medicated when they get sick. So they reach slaughtering age quicker, which means they have less time to belch methane.

Switching humans to an entirely plant-based diet would solve some of these problems, but not all of them. For one, clearing forests and peatlands—essentially sparser forests laid on a bed of slowing rotting organic matter—to make way for agricultural land destroys essential carbon sinks. Healthy forests sequester CO2 during photosynthesis and store it. In the case of mucky peatlands, they can sequester carbon for perhaps thousands of years.

Also, prior research has shown that increased CO2 concentrations in the atmosphere can actually help crops grow. “But now we know that high levels of CO2 in the atmosphere decrease protein values in grain crops, and also some micronutrients like zinc and iron,” says Cynthia Rosenzweig, a coordinating lead author on the report. Lower protein in crops might then make it even harder to wean ourselves off the easy protein of meat.

So we’re caught in a brutal tension here: We need to protect and plant more trees to sequester more carbon, but we also need more land to feed a booming human population. “We can reduce our demand, or we can increase the amount of land we grow stuff on and the number of animals that produce food,” says Van Eenennaam.

Tackling this problem will require looking at every piece of the land-use problem individually, and thinking hard about how we solve each one. For example, one way to lower the demand for food might be to eliminate the massive amount of food that gets wasted every day. But the reasons why food gets wasted vary from place to place. In the US, consumers are responsible for a great deal of it, whereas in the developing world the supply chain is the bigger culprit. There, insufficient refrigeration can cause foods to spoil before they even get to the market. The solution? More refrigeration—which means more emissions and more warming.

Researchers are racing to develop solutions to the preservation problem—a clever spray, for instance, can double the ripeness window of avocados. Robots, if deployed widely, could help fill in labor gaps and grow fruits and vegetables more efficiently, for example using machine vision to determine optimal ripeness. All great ideas that are still very young.


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