Bring your tissue to this one. On Friday, the IPCC publicizes its “emotional heart,” the Second Working Group’s contribution to the Fourth Assessment Report, covering impacts, adaptation, and vulnerability.

Preliminary drafts have been leaked. Why is it shaping up to be such a tear-jerker? According to Andrew Weaver, a lead author of Working Group I and climate scientist at the University of Victoria in British Columbia, this one illustrates “a highway to extinction, but on this highway there are many turnoffs. This is showing you where the road is heading. The road is heading toward extinction.”

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As many as one-third of the species we know are set for extinction if they’re unable to migrate en masse, accompanying another 1-2 degrees C rise (2-4 degrees Fahrenheit).

Humanity is also bound to hit a series of obstacles — some one to two billion people face water scarcity, increased drought, malnutrition, and the spread of infectious diseases. It’s true that climate change is uncharted territory, but it doesn’t have to be a crash course — or a highway to Hell and High Water.

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