PJ Hahn, an environmental consultant and former Plaquemines Parish coastal zone manager, poses for a photo on a small patch of land with mangroves, which is all that remains after the land around it eroded away, in Plaquemines Parish, La., Wednesday, Nov. 3, 2021. World leaders are gathered in Scotland at a United Nations climate summit, known as COP26, to push nations to ratchet up their efforts to curb climate change. Experts say the amount of energy unleashed by planetary warming would melt much of the planet's ice, raise global sea levels and greatly increase the likelihood and extreme weather events. (AP Photo/Gerald Herbert)