In 1789, as the French Revolution was raging, the Swiss mountaineer and physicist Horace-Bénédict de Saussure officially launched the science of the colour of the sky. That the sky is blue is a universally acknowledged truth, but de Saussure was intrigued to understand why it is blue, and whether the inhabitants of any given corner of the planet are encountering the same blue when they look up at the celestial dome.

To check this, De Saussure created the cyanometer, a paper disc with 53 different gradations of blue that allows the user to 'match' the shade of blue visible to the naked eye with a specific gradation. It thus certifies that the sky at the summit of Montblanc is a darker blue than the sky we see from the foot of the mountain. It was the legendary naturalist explorer Alexander Von Humboldt, one of the founding figures of environmentalism, who took full advantage of the cyanometer, using it to methodically measure the colour of the sky on his expeditions to the Caribbean, the Andes and the Canary Islands.

When we look at the colour of the sky, we are really observing how sunlight is scattered by particles suspended in the atmosphere, from water droplets to dust and chemicals floating in the air. In the Anthropocene, human activity is also changing, among many things, the colour of the sky. The colour palette recorded by De Saussure and Alexander Von Humboldt in the 18th century is not the same as the one we can measure today on a planet in environmental emergency. Climate change, with the multiplication of extreme events that reshape the atmosphere and the air we breathe, is introducing new colours into the sky. Forest fires turn the sky orange and produce deep red sunsets, while tropical storms and hurricanes turn the sky a violet pink. In the world's most polluted cities, with regular poor air quality alerts, a heavy, impenetrable grey colour has set in, caused by particulate matter released by fossil fuels.

There are more doomsday scenarios on the horizon. Should the climate emergency force us to take drastic measures such as spreading sulphate in the stratosphere in order to reduce the amount of sunlight entering the atmosphere, some scientists predict that we could lose the blues of the cyanometer altogether, replaced forever by a blinding white.

"Oasis (Archive of the Skies)" is a meditative space that immerses us in the colours of the celestial dome, from the blues of clear days to the multiplicity of changing tones that the sky gives us at dusk and dawn. The installation invites us to slow down the tempo and focus our attention and senses on a journey through the skies of the planet. From the explosion of colour of the aurora borealis to the murky skies produced by sandstorms, hurricanes or pollution. In addition to a sensorial immersion, this work is an appeal to be aware of the conflicts of the atmosphere, one of the central political spaces in the era of the climate crisis.

José Luís de Vicente, january 2023