Kathy Egland of Gulfport is representing South Mississippi on Friday at a climate summit hosted by the United Nations in New York.
Egland, who chairs the National NAACP Board Environmental and Climate Justice Committee, will attend a signing of the historic Paris Agreement in recognition of Earth Day.
More than 130 countries are expected to participate in the summit.
The Paris Agreement was designed under the UN's Convention On Climate Change. It will begin dealing with greenhouse emissions in 2020 and the reduction of global warming.
It was adopted in 2015 in Paris.
Egland said she applied to attend the summit but she did not think she would get accepted.
"This is an international treaty, and I'm honored to be a part of it," she said.
As a Coast resident, Egland is preparing for climate change and environmental issues.
"The Gulf Coast is my home," she said. "We survived the worst environmental disaster is history -- the BP oil spill of 2010. I want to be a voice for the people on the Coast with these heads of state from around the world."
Oil giant BP's Deepwater Horizon, an oil-drilling rig in the Gulf of Mexico, exploded April 20, 2010, initiating the release of millions of gallons of crude oil.
Six years after the oil spill, Egland said, the Coast is still reeling from the disaster.
"I don't know that you ever recover from these things," she said. "It's like Hurricane Katrina -- did we fully recover from that? You just go back and forth and stay in a constant state of recovery, and you never get back to 100 percent."