Four former Environmental Protection Agency administrators testified on Wednesday at a Senate hearing on the need to curb carbon pollution that is causing global warming. The four former administrators – William D. Ruckelshaus, Christine Todd Whitman, William K. Reilly and Lee M. Thomas – all served under Republican presidents. At a time when leading Republicans in Congress have labeled global warming a hoax, Sen. Bernie Sanders welcomed the testimony of “intelligent Republicans” who respect the overwhelming consensus of the scientific community. The hearing came two weeks after the EPA unveiled a proposal to limit carbon emissions from existing power plants. The initiative, which would reduce emissions by 30 percent from 2005 levels. President Obama’s proposal to combat global warming was supported by  67 percent of Americans in a Wall Street Journal/NBC News poll published on Wednesday.

Watch Sanders at the hearing

Read A Republican Case for Climate Action in The New York Times

“We served Republican presidents, but we have a message that transcends political affiliation: the United States must move now on substantive steps to curb climate change, at home and internationally,” the four had written in a joint column published by The New York Times.

The four former EPA administrators suggested that a carbon tax would be among the best ways to reduce greenhouse-gas emissions.

Along with Sen. Barbara Boxer, chairman of the Senate Environment and Public Works Committee, Sanders has proposed a tax on carbon and methane emissions. Their bill would create millions of jobs by investing in a transformation of our energy system from fossil fuel to green energy sources such as wind, solar, geothermal and biomass.