The world is in the grips of a dangerous heat wave that has sent temperatures skyrocketing to deadly levels throughout Asia, Europe and the Americas. Unless urgent action is taken to reduce carbon emissions, the United Nations says, Earth could pass a temperature threshold in the next decade when climate disasters are too extreme to adapt to. We speak with longtime climate journalist Jeff Goodell, author of the new book, _The Heat Will Kill You First: Life and Death on a Scorched Planet_, about how the climate crisis is raising temperatures, the toll such heat can have on the human body, and how “heat is the primary driver for this climate transformation we are undergoing right now,” fueling natural disasters such as floods, wildfires and more.