We must eat less meat and more plant-based food, as well as immediately change the way we manage land and produce food in order to limit global warming, UN scientists warned in a major report released Thursday.

The report by the UN’s Intergovernmental Panel on Climate Change examines how global warming and land interact in a vicious cycle that makes food more expensive, scarcer and even less nutritious.

“We humans affect more than 70 percent of ice-free land, (and) a quarter of this land is degraded,” said Valérie Masson-Delmotte, co-chair of the IPCC, according to CNN.

“The way we produce food and what we eat contributes to the loss of natural ecosystems and declining biodiversity,” she added.

The 1,000-page report comes almost a year after the panel concluded that we only have until 2030 to drastically reduce our dependence on fossil fuels and prevent the globe from reaching the crucial threshold of 34.7 degrees Fahrenheit above pre-industrial levels.

“When land is degraded, it reduces the soil’s ability to take up carbon and this exacerbates climate change. In turn, climate change exacerbates land degradation in many different ways,” Masson-Delmotte said.

She added: “Today 500 million people live in areas that experience desertification.”

Agriculture and its supply lines account for as much as 37 percent of all man-made emissions, according to the report, and current industrialized production and global food chains contribute to widespread food inequality.

While there are currently 2 billion overweight or obese adults, 820 million people still don’t get enough calories, the report said.

“There’s a wide range of food systems that rely on meat, and many people rely on meat for protein,” Cynthia Rosenzweig, a NASA climatologist and report author, told Agence France-Presse. “But we do need to develop low greenhouse gas meat-producing systems.”

Although the report stopped short of explicitly advocating that people become vegetarians, it called for sweeping changes to farming and eating habits to limit the impact of population growth and changing consumption patterns on stretched land and water resources.

“The IPCC does not recommend people’s diets … Dietary choices are very often shaped or influenced by local production practices and cultural habits,” Jim Skea, one of the report’s authors, told reporters in Geneva on Thursday.

“There are certain kinds of diets that have a lower carbon footprint and put less pressure on land,” added Skea, a professor at London’s Imperial College, Reuters reported.

Food waste and meat consumption are major contributors to global warming — with food waste producing between 8 percent and 10 percent and livestock 14.5 percent of global emissions, according to the World Wildlife Fund, CNN reported.

According to the report, between 25 percent and 30 percent of all food produced is never eaten. Plant-based foods and sustainable animal-sourced food could free up millions of square miles of land by 2050, the IPCC said.

The report also said deforestation is making the world hotter and hungrier. Although the report doesn’t pinpoint any country, scientists, when asked, pointed a finger at Brazil’s recent stepped-up deforestation of the Amazon.

“It contradicts all the messages that are coming out of the report,” said Hans-Otto Portner, a panel leader from Germany.

But the report offered a sobering take on the hope that reforestation and biofuel plans alone can counteract mankind’s environmental damage, stressing that reducing emissions will be vital to averting disaster.

“Land is a source of emissions as well as a sink,” IPCC chair Hoesung Lee told AFP.

“Obviously you want to reduce emissions from land as much as possible. But that has a lot to do with what’s happening to the other side of the equation: greenhouse gas emissions, mainly from the energy sector,” he said.

The IPCC said that “the window for making these changes is closing fast. If there is further delay in reducing emissions, we will miss the opportunity to successfully manage the climate change transition in the land sector,” it said.

The report text is prepared by more than 100 scientists but has to be approved by governments.

With Post wires