It is often said that the first full image of the ‘blue planet’, taken by the Apollo 17 space mission in December 1972, revealed Earth to be precious, fragile and protected only by a wafer-thin atmospheric layer, and reinforced the imperative for better stewardship of our ‘only home’.
Against these numinous readings, the NASA photograph also entrenched the apprehension of the Earth as total object and reinforced the instrumentalist conception of the Earth, that is, as an object to be used for our own ends. In this way, the ‘blue planet’ image was not a break from technological thinking but its affirmation. NASA itself writes: “From space we can view the Earth as a whole system, observe the net results of complex interactions, and begin to understand how the planet is changing in response to natural and human influences.”
Behind the photograph itself was the mode of its production, made possible by the mammoth technological feat of projecting humans into space equipped with sophisticated image-making devices. The image therefore represents a triumph of humanity’s ability to free itself from the constraints of the Earth. Moreover, it provided pictorial corroboration of the distancing of humans from the Earth and validated the conception of the planet as an independent entity ‘seen’ by humans.
In authorising the understanding of the world as object, the Apollo 17 photograph legitimised the Earth as a domain of technological manipulation. For those drawn to the mastery project, by entrenching the image of the world as a conceivable, visible total object the photograph prompts the idea that the Earth could be subject to regulation.
The competing readings of the Apollo 17 image find expression in two conceptions of nature. In one, nature is that which is ‘over there’, that which surrounds but remains essentially separate from us and is invested with an enigmatic quality demanding our respect. It is a conception that has ruled in environmentalism and allows us to aspire to ‘live in harmony with nature’, to protect it and to live sustainably within the limits it imposes. It is an aspiration concordant with the science of ecology, but which for most was never merely a scientific idea.
The second, more recent, conception is that of nature as a system. It is reflected in the dawning realisation that we can no longer isolate the impact of humans geographically, for our impact is discernible everywhere, leading to the declaration of a new geological epoch known as the Anthropocene, the Age of Humans. It is also embedded in the emergence of the new science of the Earth system that is responding to this realisation. One implication of the radical change in scientific thinking over the last two decades is that what we used to think of as ‘the environment’ – the natural world spread around us – no longer exists.
In its place we now have the Earth system, the collection of interdependent ‘spheres’ that make up the planet – the hydrosphere (the watery parts), the geosphere (the Earth’s crust and what lies beneath), the biosphere (living things) and the atmosphere (the air). Earth system science conceives of these spheres as intimately connected, linked by a myriad of planetary processes – like the carbon cycle, the nitrogen cycle and the water cycle. Everything is connected to everything else, often in startling ways we barely understand, but which are nevertheless knowable.
Thinking of the Earth as a system represents a fundamental philosophical shift. A system is a whole made up entirely of its parts. As a system the Earth becomes an entity that is distinct, certain and graspable by the human mind, the kind of entity that defines the realm of scientific understanding. Beyond that there is no longer anything of the world; that is, in the Newtonian break from scholasticism, nothing ‘with unknowable and unanalysable depth’. Replacing the ‘environment’ with the Earth system changes everything because a system is a totality within a boundary. Instead of worrying about how our activities might affect some part of the environment out there, now we must think about how we are disrupting the planet as a whole. This is the essential lesson of anthropogenic climate change.
If our influence has been so pervasive and powerful that there is no more ‘nature’, we are left only with elements of the Earth system showing various levels of human disturbance. So the default position is no longer how to minimise our impact, but how best to intervene. The goal can no longer be to ‘live in harmony with nature’, the hope enshrined in the 1992 Rio Declaration, but how to manage the Earth system.
This shift defines the divide over the interpretation of the Gaia hypothesis, James Lovelock’s notion of the Earth as a living organism. After publication of his first book, Gaia: A New Look at Life on Earth, Lovelock was dismayed by the bags of letters he received from readers who saw his vision in religious terms, as giving the Earth a meaning beyond the cold, analytical stare of science. Lovelock soon retreated from his claim that the Earth is a living organism into a more mechanical definition of Gaia, that is, as a self-regulating, purposeless, cybernetic system with equilibrating properties. He finally conceded that for him the Earth is alive only in a metaphorical sense, writing that we should imagine it to be alive so that we are more inclined to protect it.
Characterising the Earth as a system has unleashed on the planet as a whole a style of thinking – that of the engineer – that had previously been confined to particular elements of it. The Earth as a whole has been opened up to mechanical thinking, updated with the cybernetic ideas of feedback loops, control variables, critical values, system efficiency and so on. And so we arrive in the age of geoengineering. Among the various methods of climate engineering attracting the attention of scientists and venture capitalists are proposals to transform the chemical composition and biological function of the world’s oceans by spraying iron slurry across large areas to encourage algal blooms, blooms that would soak up carbon dioxide from the atmosphere and take it to the deeps. Another is to enhance the reflectivity of marine clouds, which at any time cover a quarter or a third of the world’s surface, so that they bounce more sunlight back into space.
But the geoengineering technology most likely to be deployed in the coming decades is a plan to filter the amount of sunlight reaching the Earth’s surface by injecting into the upper atmosphere a layer of sulphate aerosols, tiny particles that reflect solar radiation. Stimulated by observing the cooling effect of large volcanic eruptions, which can reduce the global temperature by half a degree or more for a few years, the particle shield would be designed to offset the warming effect of carbon emissions.
It should perhaps be no surprise that a tech titan like Bill Gates should be attracted to planetary engineering. Here it is not his values that are questionable – his philanthropic activities reflect a deep concern about the future conditions for humanity – but his world-view, the belief that there is an app for everything, including an ailing planet. Yet the question arises of whether the Earth will allow itself to be treated as a system subject to technological control, or whether it retains some ‘unknowable and unanalysable depth’ that will elude all human attempts to comprehend, let alone conquer.