Our fragile planet

Climate is an informative introduction to the subject of climate change. Though climate change is normal in Earth's history, global warming has raised average temperatures to their highest in two millennia, resulting in melting ice caps, shorter winters, changes in the seasonal behaviors of animals, and more extreme weather. And though greenhouse gases are essential for keeping the planet's temperatures comfortable, fossil fuel burning, and other...

An introduction to how life in our oceans works, and how we are threatening it with pollution and depletion of fisheries.