Olafur Eliasson and Minik Rosing's Ice Watch review: Big freeze comes early with an urgent warning of climate crisis

The first thing that strikes me when I see the blocks of ice that Olafur Eliasson and geologist Minik Rosing have gathered outside Tate Modern and Bloomberg HQ is their sheer beauty.

Each one is distinctive: some are crudely blocky, others appear sculpted by nature. Their purity was enhanced on a cool London morning: in the stark, low winter sun, it’s as if they suck the light in, holding it in a misty aquamarine at their heart. The dense bodies of opaque compacted snow are interrupted by thick bands of more pellucid icemelt and, at the edges, transparent halos on the cusp of liquifying. Look closely and you see the tiny pockets of air that pop and crackle if you put your ear to the blocks. It’s “a concert of bubbles”, Eliasson says.

They’ve come from a Greenland fjord, where they and 10,000 others per second are being lost from the ice sheet into the ocean. Their beauty is important: if we’re to comprehend the effects of climate change, then seeing glaciers’ fragile wonder in the flesh makes it more palpable. As Eliasson says, seeing it melt before your eyes conveys the urgency with which we must act in a way that graph or text can never do.

Because time is Ice Watch’s most crucial element, it’s arranged like a clock, with a ring of 12 equidistant boulders in a circle which the others inhabit. The glaciers contain hundreds of years of historic snowfall but it’s melting over the course of a few days. This evokes not just the speed with which the ice sheet is disappearing, and causing alarming sea-level rises, but also the diminishing time in which we can make a difference: the Intergovernmental Panel on Climate Change (IPCC) puts it at just 12 years to prevent warming rising from 1.5C to 2C, with catastrophic results.

Ice Watch isn’t subtle but there’s no time for ambiguities: this is art as a spectacular call to action.

Until around Dec 21, weather permitting (icewatchlondon.com)