In 2015 Mr. Deese took on the role of senior adviser to Mr. Obama on climate change and energy, where he helped drive sweeping regulations cutting emissions from the electricity sector and from vehicle tailpipes as the United States prepared to join the Paris agreement on global warming. President Trump has over the past four years repealed those regulations and dozens of others addressing climate change and withdrawn the United States from the Paris accords.
But Mr. Deese’s post-Obama administration role as global head of sustainable investing at the BlackRock, the world’s largest asset manager, has drawn criticism from many environmental activists on the left.
Earlier this year Laurence D. Fink, the founder of the investment behemoth, announced that it would shift its investment policy to make climate and sustainability central to its goals. But green groups say the company has not gone far enough to abandon fossil fuels. One campaign led by progressive groups dubbed Mr. Deese as “chief greenwasher” of BlackRock and questioned his commitment to fighting climate change.
Others have come to his defense, notably Bill McKibben, the activist and co-founder of the environmental group 350.org. In a Twitter thread this week Mr. McKibben, a former Sunday school instructor, described having Mr. Deese’s future wife in his class when she was a child and years later performing their wedding. Mr. McKibben praised Mr. Deese’s work in the Obama administration as well as for BlackRock, and pushed back against criticisms.
“I know he cares a lot, and works hard on the issue,” Mr. McKibben wrote. “Since — because of pure chance — I know Brian to be both able and decent, and because I know he in fact does care about climate, it felt like I had to say something.”
Laurence Tubiana, who served as France’s top climate negotiator during the Paris agreement, said Mr. Deese helped bring countries together to sign the pact. Todd Stern, the State Department climate change envoy under Mr. Obama and a chief architect of the accords, called Mr. Deese “a dedicated proponent of ambitious climate action” who “gets the scale and speed of the net-zero transformation we need.”
Mr. Biden has pledged to deliver $2 trillion over the next four years to reduce planet-warming emissions and dramatically increase the amount of renewable energy used for electricity generation and transportation. He has made climate change a central part of his economic plan, as well as his White House structure.