Review: Sea Sick (Canada Hub Summerhall, Edinburgh)

Theatre directors and playwrights have been agonising for decades about the best way to bring the most pressing issue of our age – the effects of climate change – to the stage. Writer Alanna Mitchell has thrown all such worries out of the window: she rocks up with a few Bob Dylan songs and a blackboard and proceeds to scare the living daylights out of you with the results of her journalistic research.

It's more a lecture than a theatre piece, but it is devastatingly effective as Mitchell – a warm and authoritative presence – firmly turns the audience's attention to the oceans which take up 99 per cent of living space on the planet. If everything on land dies, the planet can still survive. If everything in the ocean dies, it's doomsday.

Yet Mitchell argues, mankind is setting the stage for a mass extinction on a scale not seen for 252 million years. Our burning of fossil fuels and the release of carbon dioxide into the atmosphere is both warming and raising the PH levels in the seas. "The ocean is warm, breathless and sour," she warns us.

Mitchell's good at explaining the science through simple means; she's also excellent at creating a sense of wonder both at the beauty of the natural world and our sheer profligacy and lack of care in squandering its miracles. Her descriptions of coral spawning, of travelling to the deep in a tiny submersible are vivid and engrossing. In contrast, the facts she assembles are utterly chilling.

The only time, in fact, that her talk falters is when she tries to offer an uplifting conclusion. Having discussed the sea with marine biologists who believe that the outlook is worse than we could ever imagine, she then offers a hopeful peroration: the future is still in play, we can do something. It doesn't entirely ring true but she might be right. Certainly Sea Sick is a call to arms.

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