San Francisco Supervisor Rafael Mandelman introduced a resolution Tuesday that would declare a state of climate emergency for the city. The move follows similar actions taken by Berkeley, Richmond, Hayward and Oakland.

Mandelman says San Francisco has been on the forefront of reducing greenhouse emissions, but needs to do more to prepare for rising sea levels, extreme weather and air pollution.

“We have actually done some great work to reduce our greenhouse gas emissions by 30 percent since 1990, but we know that we need to do a whole lot more," he said.

The climate emergency declaration instructs city departments such as housing and transportation to work together over the next 100 days to devise a plan for meeting the city’s goals of zero net greenhouse gas emissions by 2050.

“The Board of Supervisors is calling on our department and city agencies to work with an intensity that we might not have been working at otherwise," said San Francisco Department of the Environment Director Debbie Raphael. "It's an acknowledgement that we can do better, we can do more, and we must.”

Mandelman says climate plans should prioritize communities of color and low-income neighborhoods that have historically borne the burden of environmental contamination and fossil fuels. 

Bayview-Hunters Point, for instance, is in a major flood zone.

“We are going to be ground zero for [rising sea levels] in Bayview-Hunters Point,” said Michelle Pierce, executive director of Bayview Hunters Point Community Advocates.

Pierce says a critical way to reduce greenhouse gas emissions is by tackling public transportation on a regional level.

“We have to reduce the costs of transit for people if we want to get them out of their cars or into electric vehicles. We have to intensively build out infrastructure for transportation, commit to subsidizing new systems, new public transit.”

Raphael, of the city's Department of the Environment, says addressing trucks that spew diesel exhaust in communities of color will also need to be a top priority when considering plans to increase use of electric vehicles.

Mandelman said having "good values" isn't enough. "We also have to implement good policies and do it aggressively and quickly."

If the San Francisco Board of Supervisors approves the resolution, city agencies will have 100 days to prioritize actions for reducing greenhouse gases.