Tortoise In Peril

The ocean is a sponge for all the greenhouse gas emissions we produce, and entire aquatic ecosystems are beginning to collapse. Off the coast of California, the disappearing abalone population is raising flags about ocean health and the lasting impact of rising sea temperatures, acidification and pollution. Various teams of scientists, volunteers and businesspeople are collaborating to protect underwater species threatened by the invasion of sea urchins.

Louisiana still is learning from Hurricane Katrina. Forecasts are dire for Louisiana to experience the second-highest sea level rise in the world. There is a big movement brewing in New Orleans to build adaptive "resilience zones." In Southeast Louisiana, the native peoples of the Isle de Jean Charles have become the first U.S citizens moving within their homeland displaced by climate change.

Populations are dramatically shifting as climate change drives migration. Droughts and floods are driving many people away from their rural, farming communities into big cities. We see how this is manifesting in Mongolia and examine the factors leading to the new community of Haitian people living in limbo at the border between Mexico and the U.S.

Two cities, San Francisco and Freetown, brace for climate change using vastly different methodologies. San Francisco's developers are building expensive real estate on floodplains as officials try to heed expert projections on future sea levels. On the other side of the world, a deadly mudslide caused by torrential rains and deforestation in Sierra Leone shows the consequences of city planning that doesn't take climate change into account.

Anticipating future water needs, two regions on opposite sides of the world turn to technology for answers. Western Morocco, near the Sahara Desert, is currently facing unprecedented drought and groundwater mismanagement. But an ancient method of gathering moisture from fog is being taught to 13 villages, allowing people to have a level of local control over their most basic need. In Central Valley, California, the food basket of the world uses nearly 80 percent of the entire state's water supply.