Scientists Warn the World Is About to Reach 'Peak Meat'

When it comes to meat, the world's plate is more than half full. In fact, scientists say it's fast approaching a tipping point.

In a letter published in the The Lancet Planetary Health Journal, 50 international scientists and environmental experts warn that the world will reach "peak meat" by 2030.

If the livestock industry doesn't stop growing by then, we literally risk eating ourselves out of house and home.

The scientists note that the world needs to keep global temperatures within a "safe" limit of between 1.5 and 2 degrees Celsius above pre-industrial levels. To get there, an estimated 720 billion tonnes of CO2 must be removed from the atmosphere.

And livestock production — a major source of emissions — will have to adopt a crash diet.

"If the livestock sector were to continue with business as usual, this sector alone would account for 49 percent of the emissions budget for 1·5°C by 2030, requiring other sectors to reduce emissions beyond a realistic or planned level."

While it's long been known that meat consumption isn't sustainable — at least not when there are 7 billion mouths to feed on this planet — the world's appetite continues to grow. And meat's environmental footprint is growing along with it.

That means increasing amounts of land are being taken up by livestock, removing natural carbon sinks like forests and vegetation along the way. Those carbon sinks play a crucial role in absorbing carbon dioxide from the atmosphere.

In the letter, scientists say all but the poorest counties need to curb their meat enthusiasm, and set a time frame to halt the industry's growth. Specifically, governments need to restructure their meat industries, zeroing in on the biggest producers of emissions and occupiers of land.

Those producers would need hard targets in place for reducing growth. Change doesn't have to be so painful for those producers, but only if they begin diversifying their food production.

Livestock, they note, could be gradually replaced with "foods that simultaneously minimise environmental burdens and maximise public health benefits."

In other words, crops like pulses, grains, fruits and vegetables. Even nuts, which require intensive amounts of water to grow, take less of a toll on the planet than red meat production.

"We're suggesting agriculture transitions to optimal systems, and that's plant-based," Helen Harwatt, an environmental social scientist at Harvard Law School and lead author of the letter, tells CNN.

It wouldn't be the first time scientists have called on rich and middle-income countries to slow down meat production for the sake of the planet. In fact, earlier this year, a United Nations panel on climate change warned of "irreversible impacts on some ecosystems."

Meat producers, however, aren't so sure.

"To say that cutting livestock numbers everywhere is the most efficient way of reducing emissions massively overgeneralises a situation that differs significantly across the world, and can hinder the countries that are practicing sustainable farming methods and have an ambition to do more," Stuart Roberts of the National Farmers' Union of England and Wales, explains to CNN in a statement.

Not surprisingly, Roberts paints a much rosier picture of the livestock industry's impact on climate change.

"Grazing cattle is the most sustainable way to use land for food production which is unsuitable for growing any other crop," he notes. "By using our grasslands in this way we can sequester carbon at the same time as turning inedible grass into a highly nutritious protein which our growing population can enjoy."