Bill Gates is a climate change philanthropist and evangelist.
But he knows full well that his life as a billionaire and business tycoon also makes him an "imperfect ambassador for climate change", he writes in his new book "How to Avoid a Climate Catastrophe".
"I can't deny I'm a rich man with an opinion," writes Gates, who is worth more than $ 100 billion, has a huge home in Medina, Washington (known as the "Xanado 2.0") and uses a private jet (which helps) he does the worldwide work of the Bill and Melinda Gates Foundation, he said on Reddit).
"It is true that my carbon footprint is absurdly high," writes Gates in his new book.
"I own big houses and fly in private planes – in fact, I brought one to Paris for the climate conference – so who am I to teach someone about the environment?" he writes.
Gates says he long felt guilty about its high emissions, but "Working on this book made me even more aware of my responsibility to reduce them," he writes. "Reducing my carbon footprint is the least that can be expected from someone in my position who is concerned about climate change and who publicly calls for action."
(Gates' disproportionate consumption of carbon-emitting fossil fuels is representative of a larger global trend: The "1%" are the main drivers of climate change, while the poorest are hardest hit.)
According to Gates' book, it started using sustainable jet fuel in 2020 and "will fully offset my family's aviation emissions by 2021".
According to the International Air Transport Association (IATA), the trade association for the world's airlines, sustainable jet fuel is not made from fossil fuels. According to IATA, it can be made from any number of raw materials, including cooking oil, vegetable oils, municipal waste, exhaust fumes and agricultural residues.
For Gates' non-aviation emissions, he writes that he "buys offsets through a company that operates a facility that removes carbon dioxide from the air."
A carbon offset is a reduction in carbon emissions in order to offset the emissions generated elsewhere. In particular, "offsetting carbon means reducing or removing one ton of carbon dioxide (CO2) from the atmosphere," said Anne Thiel, communications manager at Verra, a Washington, DC-based nonprofit. Carbon dioxide is used as a reference point because it is the most abundant greenhouse gas in the atmosphere and "stays in the climate system for a very long time," says Thiel.
It's worth noting that some criticize the idea of carbon offsetting as a convenient loophole for more permanent solutions. Others, however, see it as better than nothing.
"Businesses should carefully set and work towards a net zero target, and we should all stick to those targets. In the meantime, however, we must now find a way to reduce emissions in order to avoid catastrophic climate change," says Naomi Swickard. the Chief Program Officer at Verra. "Offsets are one of the most efficient, short-term ways to drive funding to real emissions reductions so we can turn the corner and stay below the turning points of the planet – giving us time for the longer term transition."
Gates writes that he also invests in clean energy companies and nonprofits. For example, in 2015 Gates pioneered Breakthrough Energy, a venture capital fund that invests in technology for climate innovations "that will lead the world to net zero".
Net zero emissions mean getting to a place where no new emissions are released into the atmosphere overall. "The emissions will persist, but will be offset by absorbing an appropriate amount from the atmosphere," said the United Nations.
"I've put more than $ 1 billion into approaches that I hope will help the world go to zero, including affordable and reliable clean energy and low-carbon cement, steel, meat and more," writes Gates in his book.
"Of course, investing in companies doesn't reduce my carbon footprint. However, once I have chosen winners, they are responsible for removing much more carbon than my family or myself are responsible for," Gates writes.
"Besides, it's not just a person's goal to offset their emissions, but to avoid a climate catastrophe."
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