Bill Gates has announced he is stepping down from the board of Microsoft and Berkshire Hathaway. The American business magnate wants to dedicate more of his time to his “philanthropic priorities,” including fighting the climate crisis.

Gates—who founded Microsoft with Paul Allen in 1975—says he will still work closely with the tech giant’s current chief executive Satya Nadella. “I feel more optimistic than ever about the progress the company is making and how it can continue to benefit the world,” he wrote in a post on Linkedin.

Gates will now spend more time working with the Bill & Melinda Gates Foundation, which he co-founded with his wife Melinda in 2000.

Since it was launched, the foundation has focused predominantly on improving global health—one of its key focuses is eradicating malaria around the globe. In February, it pledged $100 million to fight the novel coronavirus.

The organization announced earlier this year that the climate crisis had emerged as one of its priorities.

‘Climate Change Makes More People Susceptible to Disease’

Gates believes that the fight against climate change and work to improve global health are interlinked.

“Global health will always be a core focus of our foundation,” he wrote in a letter on Gates Notes earlier this year. “This work will only become more important in the future, as climate change makes more people susceptible to disease.”

He added: “people all over the world are already being affected by a warmer world. Those impacts will only get worse in the years to come. The cruel irony is that the world’s poorest people, who contribute the least to climate change, will suffer the worst.”

Animal agriculture is a leading cause of climate change. Livestock emits 14.5 percent of the world’s annual greenhouse gas emissions, according to the Food and Agriculture Organization of the United States. It’s also responsible for significant amounts of deforestation, water use, and land use.

Gates has acknowledged that plant-based food is more sustainable. In 2013, he invested in vegan meat brand Beyond Meat.

Recently he spoke about the environmental impact of eating meat in a YouTube video with former NASA engineer Mark Rober. The pair ate plant-based hamburgers and bratwurst.

Gates said: “the quality is going to keep getting better. You know, the plant-based guys are not done innovating. Eventually, they claim, you won’t be able to tell the difference.”