Despite Gina McCarthy’s tough-on-carbon rhetoric, the power plant rules just unveiled by the Environmental Protection Agency administrator simply don’t cut planet-warming pollution quickly enough to help avert a climate crisis [“ McCarthy is breath of fresh air at EPA,” news, June 2].

Close examination reveals that the EPA plan aims to reduce existing power plant emissions about 7.7 percent below 1990 levels by 2030. But scientists warned years ago that developed countries, including the United States, must reduce emissions far more — 25 to 40 percent below 1990 levels by 2020. McCarthy’s plan is nearly three-quarters too little and 10 years too late.

The National Climate Assessment recently predicted as much as four feet of sea-level rise by 2100 without deep cuts to pollutants.

To fight that threat, the EPA must strengthen these draft power plant rules. If we keep kicking the can down the road, the cost and difficulty of averting a global warming catastrophe will skyrocket.

Kevin Bundy, San Francisco

The writer is a senior attorney for the Center for Biological Diversity.