President-elect Joe Biden added more than a half-dozen climate staffers to his White House team Thursday, drawing from the ranks of green groups, environmental justice advocates and former Democratic administration officials to grow an inner circle that will help him try to slash the nation’s greenhouse gas emissions. The new hires include David J. Hayes, who served as Interior deputy secretary under Presidents Bill Clinton and Barack Obama; Cecilia Martinez, a prominent environmental justice advocate based in Minneapolis who advised the transition team; and Stef Feldman, a top Biden campaign aide who helped craft his climate plan. They will work with several incoming Cabinet officials new to Biden’s orbit, including North Carolina environmental regulator Michael S. Regan, picked to run the Environmental Protection Agency, and Rep. Deb Haaland (D-N.M.), set to serve as interior secretary.

The incoming White House team — which also includes former secretary of state John F. Kerry and former EPA administrator Gina McCarthy, along with Obama administration veterans in the National Security Council and the White House Counsel’s Office — represents the most robust climate-focused group assembled in the West Wing.

Biden, set to take office in less than a week, will try to execute a far-reaching strategy to embed climate action across government agencies and in legislation on Capitol Hill. He has also pledged to address the disproportionate pollution burden carried by poor and minority neighborhoods.

In a recent interview, John Podesta, who helped spearhead Obama’s second-term climate agenda as senior counselor to the president, noted that Biden has assembled more expertise on the subject than any of his predecessors. When Obama first came into office, he brought on former EPA chief Carol Browner as a senior climate adviser with just minimal staff. Podesta also operated informally during his time in the White House, using long-established relationships and his access to the president as a way to mobilize action in several departments.