Climate change is the epic challenge of our lives, and community leaders like Rahwa Ghirmatzion and Zelalem Adefris are already working on sustainable, resilient solutions. Through their organizations in Buffalo and Miami, they're focused on durable, affordable housing for under-resourced communities, the most vulnerable to the instability of climate change. Watch for a lesson on how we can work alongside our neighbors to address climate catastrophe and social inequality. (Narrated by Don Cheadle)

Concrete is all around us: we use it to build our roads, buildings, bridges and much more. Yet over the last 2,000 years, the art of mixing cement and using it to bind concrete hasn't changed very much -- and it remains one of the world's biggest emitters of carbon. Entrepreneur Tom Schuler previews an innovative way to create concrete, potentially turning it into a carbon sink that traps CO2 from the atmosphere -- while producing a viable building material.

Concrete is the second most-used substance on Earth (behind water), and it's responsible for eight percent of the world's carbon footprint. Cement researcher Karen Scrivener shares the research behind a pioneering new kind of cement known as LC3, which could slash carbon emissions from this crucial building material by 40 percent, if adopted at scale.

Concrete is the second most-used substance on Earth (behind water), and it's responsible for eight percent of the world's carbon footprint. Cement researcher Karen Scrivener shares the research behind a pioneering new kind of cement known as LC3, which could slash carbon emissions from this crucial building material by 40 percent, if adopted at scale.

"The good news is it's now clearly cheaper to save the planet than to ruin it," says engineer and investor John Doerr. "The bad news is: we are fast running out of time." In this conversation with climate policy expert Hal Harvey, the two sustainability leaders discuss why humanity has to act globally, at speed and at scale, to meet the staggering challenge of decarbonizing the global economy (which has only ever increased emissions throughout history) -- and share helpful examples of promising energy solutions from around the world.

We need to care for and live in harmony with the environment, says climate and gender activist Ernestine Leikeki Sevidzem. The best way to do that? Nurture a forest generation: one that learns to protect nature. Sevidzem shares how she's educating both children and adults in her native Cameroon on what it means to love and preserve the Earth -- and calls for all of us to foster generations that will inherit a mindset that works with nature, not against it.

Biodiversity is the key to life on Earth and reviving our damaged planet, says ecologist Thomas Crowther. Sharing the inside story of his headline-making research on reforestation, which led to the UN's viral Trillion Trees Campaign, Crowther introduces Restor: an expansive, informative platform built to enable anyone, anywhere to help restore the biodiversity of Earth's ecosystems.

"Nature reveals itself to us in unique ways, if we stop and look at the world through a window of time," says photographer Stephen Wilkes. Using a special photographic technique that reveals how a scene changes from day to night in a single image, Wilkes exposes the Earth's beautiful complexity and the impacts of climate change -- from the disruption of flamingo migrations in Africa to the threat of melting ice -- with unprecedented force.

With the Climate Reality Project, Al Gore is helping mold future leaders to build the movement for climate survival and social justice from the ground up. He introduces us to four of the Project's graduates, each of whom confronts climate change on their own terms: Ximena Loría, founder of Misión 2 Grados, an NGO influencing public policy in Central America; Nana Firman, "daughter of the rainforest" and advocate for climate justice among Indigenous peoples; Gloria Kasang Bulus, a Nigerian activist for women and education; and Tim Guinee, a first responder and climate change fighter in upstate New York. Together, they're gathering local actors into a global, grassroots movement that aims to turn the climate fight around.

With the Climate Reality Project, Al Gore is helping mold future leaders to build the movement for climate survival and social justice from the ground up. He introduces us to four of the Project's graduates, each of whom confronts climate change on their own terms: Ximena Loría, founder of Misión 2 Grados, an NGO influencing public policy in Central America; Nana Firman, "daughter of the rainforest" and advocate for climate justice among Indigenous peoples; Gloria Kasang Bulus, a Nigerian activist for women and education; and Tim Guinee, a first responder and climate change fighter in upstate New York. Together, they're gathering local actors into a global, grassroots movement that aims to turn the climate fight around.