What does it mean to lose a colour? Losing Blue is a cinematic poem that delves into the impending loss of some of the most extraordinary blues on Earth—the otherworldly blues of ancient mountain lakes.

Glacier-fed alpine lakes each have a unique blue formed by the mountains and ice that shaped them. These intense colours hold the memory of “deep time,” geological processes millions of years old. Now climate change is rapidly accelerating environmental shifts and causing some of these spectacular blues to vanish.

Losing Blue is an expansive metaphor for the massive and subtle impacts of climate change. With stunning cinematography, the film immerses viewers in the magnificence of lakes so rare that most have never seen them, pulling us in so that we experience these bodies of water as if we were standing alone on their rocky shores—witnesses to their power and acutely aware of what their loss would mean, both for ourselves and for the Earth.

Filmmaker Leanne Allison’s narration intimately balances J.B. MacKinnon’s eloquent science writing. This short documentary gently asks what it might mean to forget that the ethereal blues of these lakes ever existed.