Overview - Season 3

Each fall, a remote stretch of volcanic sand in Costa Rica transforms into one of nature's greatest spectacles: Tens of thousands of sea turtles arrive en masse and nest in unison. But this breathtaking event hides a surprising paradox that may actually help save the species.

At a rocket test range in Alaska, scientists are firing rockets into the northern lights. They want to better understand the aurora because they are the visible fingerprint of a powerful and dangerous force that can disrupt GPS, satellites, and power grids. We join them at a launch to find out what they've discovered.

America's most toxic lake may also be one of its most overlooked resources. At the Berkeley Pit Superfund Site, scientists are extracting clean energy materials from a century of mining waste.

We investigated one of the world's largest AI data centers, using thermal drone footage to reveal the hidden pollution powering the AI boom. As companies race to build the future of artificial intelligence, residents and experts warn that fossil fuels, secrecy, and weak regulation may be putting communities at risk.

In 2011, a fire in the Great Dismal Swamp burned for 111 days. Even a foot of rain from Hurricane Irene failed to extinguish it. The reason was hidden underground in layers of peat, one of Earth's most important carbon stores. What started this fire reveals a surprising story about climate change, America's complicated history, and one of the continent's most remarkable landscapes.