CHICAGO — The Latest on a Chicago summit on climate change (all times local):

4:05 p.m.

Former President Barack Obama says cities, states and nonprofit groups have emerged as “the new face of leadership” on climate change.

He briefly spoke Tuesday to a summit of mayors from around the world gathered in Chicago to address concerns about climate change since President Donald Trump rejected the Paris climate accord. The mayors signed a charter that echoes portions of the 2015 Paris agreement.

Obama didn’t mention Trump by name, saying only that the U.S. was in an “unusual” position as the sole country to reject the Paris agreement.

Trump announced earlier this year that the U.S. would pull out of the Paris accord, which involves nations setting benchmarks to reduce emissions of heat-trapping gases. The U.S. won’t technically back out until 2020 because of legal technicalities.

Mayors from more than 50 cities attended the summit, which began Monday evening.


3:20 p.m.

Mayors from around the globe who signed a charter in Chicago pledging to fight climate change have different concerns for the coming years.

Mexico City Mayor Angel Mancera says in a statement that his sprawling capital of about 9 million is committed to combating climate change through programs such as ensuring all residents have access to alternative transportation like walking and cycling, as a matter of land use policy. Mancera says the city is trying to accelerate a transition to soot-free engines and procure zero-emissions buses by 2025 with an overall zero-emissions goal for most of the city by 2030.

San Francisco Mayor Ed Lee says rising water levels and affordable housing are concerns for his city.

Chicago Mayor Rahm Emanuel noted ramped-up efforts to make dozens of buildings in the city more energy-efficient.


1:25 p.m.

Dozens of mayors from around the world have signed a “Chicago Climate Charter” at a summit designed to address concerns following President Donald Trump’s rejection of the Paris climate accord.

Former President Barack Obama is expected to address the crowd Tuesday afternoon, following sessions on transportation, energy and waste management for mayors from cities including Paris, Mexico City, San Francisco and Phoenix.

Chicago Mayor Rahm Emanuel says climate change can be solved by human action.

The charter calls for mayors to achieve a percent reduction in greenhouse gas emissions that’s equal or more than outlined in the Paris agreement. It also calls for them to work with scientific and academic experts to find solutions.

Some mayors have specifically agreed to commitments to expand public transportation and invest in natural climate solutions such as tree canopy and vegetation.


9:45 a.m.

Former President Barack Obama is expected to address mayors from around the world at a Chicago summit to discuss climate change.

Officials are billing the North American Climate Summit that began Monday as the first of its kind for the city.

Chicago Mayor Rahm Emanuel told the gathering Tuesday that mayors are stepping up because there’s no consensus from national governments.

President Donald Trump said in June that the U.S. will withdraw from the Paris climate accord. Without mentioning Trump by name, Emanuel, a former White House chief of staff to Obama, said Trump is in denial on climate change but shouldn’t ignore science.

Mayors from 51 cities are attending and will sign a charter outlining planned actions. Among the non-U.S. mayors attending are the mayors of Montreal and Mexico City.


12:15 a.m.

Former President Barack Obama is expected to address a gathering of mayors from around the globe convening in Chicago to discuss climate change after President Donald Trump said the U.S. will pull out of the Paris climate accord.

Chicago officials are billing the North American Climate Summit Chicago as the first of its kind in the city. Chicago Mayor Rahm Emanuel says he’s honored Obama will join the summit, which kicked off Monday evening and wraps up Tuesday.

Chicago’s Chief Sustainability Officer Chris Wheat says the idea is to “fill the void” the Trump administration has left. He says mayors will sign a charter and discuss solutions including expanding access to public transportation.

Other mayors attending include Valerie Plante of Montreal and Miguel Angel Mancera of Mexico City.