By Dr. Robert Talbot, Professor of Atmospheric Chemistry & Director of Institute for Climate and Atmospheric Science
The Trump administration formally proposed Tuesday to scrap the Obama administration’s signature climate change rule for power plants. The plan was meant to curb emissions of carbon dioxide from coal- and natural-gas-fired power plants, which are responsible for about one-third of the U.S.’s carbon dioxide emissions.
Carbon dioxide is the primary greenhouse gas in the Earth’s atmosphere, causing global warming. Today, China is the largest emitter of carbon dioxide, but the U.S. is the clear leader in cumulative emissions over the past several decades (Figure 1).
When the Clean Power Plan was unveiled in 2015, it had a goal of cutting power industry emissions by 32%. Many states were already shifting away from coal for economic reasons. This reversal could slow the transition.
Environmental Protection Agency (EPA) chief Scott Pruitt signed the notice Tuesday, arguing that former President Barack Obama’s 2015 rule, dubbed the Clean Power Plan, exceeds the agency’s authority under the Clean Air Act. Environmentalists and Democrats have pledged to fight the rollback. Environmental groups and some states plan to challenge the new plan based on scientific and economic grounds.
The scientific evidence of the need to continue to curb emissions is overwhelming. The last two years have seen the largest increase of carbon dioxide in the Earth’s atmosphere – more than 3 ppm (parts per million) per year based on National Oceanic and Atmospheric Administration’s data from Mauna Loa (Figure 2).