Peter Singer: The Simplest Way to Change the Planet’s Fate

MELBOURNE, Australia — The year of the first Earth Day, 1970, was the year I stopped eating meat. I didn't do it to save the Earth, but because I realized that there is no ethical justification for treating animals like machines for converting feed into meat, milk and eggs. It is wrong to ignore or discount the interests of sentient beings because they are not members of our species.

In the United States and beyond, giant agribusiness corporations continue raising animals in ways that disregard their welfare, never allowing pigs or chickens to walk outside, crowding hens who lay eggs into cages that prevent them from stretching their wings and breeding chickens to grow so fast that their immature leg bones struggle to bear their weight.

Boycotting this monstrous abuse of billions of animals each year is a powerful reason for not eating meat, but the outsize contribution of meat and dairy products to climate change is for me now an equally urgent part of shifting to a plant-based diet. But we need not be hard-line about avoiding all animal products. If everyone chose plant-based foods for just half their meals, we would have fewer animals suffering, and a tremendously better shot at avoiding the most dire consequences of climate change.

Meat and dairy production are major sources of methane, a powerful greenhouse gas. The Intergovernmental Panel on Climate Change calculates that releasing into the atmosphere a ton of methane will, over a century, raise the temperature of our planet by 28 times as much as releasing a ton of carbon dioxide. That would be bad enough, but the impact is even more lopsided in the shorter term: Because methane breaks down much more rapidly than carbon dioxide, over 20 years, that ton will warm the planet as much as 84 tons of carbon dioxide...

https://www.nytimes.com/2023/04/22/opinion/earth-day-climate-change-meat-vegan.html?action=click&module=Well&pgtype=Homepage&section=Guest%20Essays