The Weather Project is, essentially, a vast optical illusion. As the visitor enters the building, he is confronted by what looks like a gigantic illuminated orange disc suspended from the ceiling at the far end of the hall. Discreetly placed humidifiers pump a mixture of sugar and water into the air to create a fine mist.
Seen through this soft haze, the light of the great disc is filtered and diffused so that it looks like the flaming ball of the setting sun. Then, as we start to walk down the long entrance ramp, we realise that the entire ceiling is covered in what appears to be a single huge mirror. The tiny specks of humanity we see far, far, above us are our own reflections.
That is the illusion. The reality is that Eliasson has hung a semi-circle of light from the mirrored ceiling in such a way that its reflection creates the appearance of a full circle. There is not just one mirror on the ceiling but hundreds, fractionally offset where they are joined. This makes the edges at the upper (illusory) half of the great disc appear slightly jagged or uneven, which is what makes the ball of light look so uncannily like the sun. Had the mirrors on the ceiling been level or flat, we would see a perfect circle and the whole thing would have looked unreal.
What the artist began, the audience completes. It is the visitors that make The Weather Project unforgettable. From any distance at all, people in the Turbine Hall are seen as tiny black silhouettes against a field of orange light. Minuscule in scale and robbed by the orange glow of their individuality, they are diminished by the spectacle they have come to the Tate to see.
Paradoxically, the less we look like individuals, the more aware we become that we share a common humanity, that we are all members of the same species. Against the cataclysmic beauty of the evening sun, we sense our insignificant place within the infinity of our solar system.
When I first saw The Weather Project, I thought of the sun rising through vapour in one of J M W Turner’s landscapes. But, late on a Saturday or Sunday afternoon, when hundreds of people stand mesmerised in the face of the glowing disc, the work becomes truly frightening, a modern interpretation of one of John Martin’s or Francis Danby’s apocalyptic visions of the end of the world. A close encounter of the third kind.
Not only does the audience help to create Eliasson’s work of art, but, in the weeks since the exhibition opened, the behaviour of that audience has added another layer of meaning to it.
Visitors respond not only to the circle of light, but also to the mirror above their heads. Adults and children lie on their backs staring up at the ceiling, often moving their arms and legs in a sweet, sad effort to find their own reflections in the swarming mass of undifferentiated shapes in the distance.
It is as though some deep primeval instinct compels us to do something – waving our hands, scissoring our legs, huddling in groups, forming shapes with our partners – to reassure ourselves of our individual existence in the universe.
What this great artist has done, literally, is to hold up a mirror and shown us who we are.