From a masked Tokyo commuter in a crush to the plastic particles killing our oceans, the former UN secretary-general hails the photographers shortlisted for tonight’s space-themed Prix Pictet prize

We are running out of space. Fly over Africa at night and you will see mile after mile of fires burning red in the dark as scrub is removed to make way for human beings. Satellite images of nocturnal Europe or America show vast areas lit up like an enormous fairground. From Shanghai to Sydney, from Moscow to Mexico City, the skylines of our major cities are no longer fixed and familiar. Where we cannot build into the sky, we construct vast chequerboards of smogbound, low-rise dwellings that stretch from one horizon to the other.

Our cities expand in every direction as we fight to house a population that is growing at the rate of 200,000 each day. That adds up to a headcount the size of Germany every year. To feed this growing number requires ever more land to farm: each year, more than 150,000 square kilometres of natural forest are lost to agricultural or urban development.

Facebook Twitter Pinterest Brilliant artificial worlds … Mandy Barker’s photograph of a specimen she collected from the Cork shoreline. Photograph: © Mandy Barker, Prix Pictet 2017

Forests cover a third of our planet’s land surface. They produce life-giving oxygen and, by absorbing carbon dioxide, also mitigate the otherwise catastrophic effects of climate change. Not only do they provide a habitat for many of the world’s most endangered animals, around 1.6 billion people rely on them for food, fresh water, clothing, traditional medicine and shelter. Yet they are under threat from rampant deforestation in its many forms: fires, clearing for agriculture, unsustainable logging, ranching and development.

We speak reverentially of the savage beauty and teeming biodiversity of the world’s great wildernesses, from the tropical rainforests of Amazonia and central Africa, to our wetlands and deserts, and on to Patagonia and the frozen wastes of Antarctica. We are increasingly aware of the threats to such spaces and have encouraged sustainable conservation and ecotourism. But still the threats remain.

The greatest unexplored space on our planet lies beneath the oceans. Yet rising CO 2 levels in the atmosphere are causing acidification, which disrupts food chains and marine habitats. Huge floating masses of plastic dumped in the oceans turn into hazardous waste that endangers not only marine life but also, indirectly, human populations – and the planet itself. Overfishing, illegal and damaging trawling practices and past whaling have emptied the oceans before we have even properly understood what riches they contain. And the great spaces of the oceans are the lungs of the planet.

Facebook Twitter Pinterest The refugee crisis in black and white … detail of a shot from Richard Mosse’s Heat Maps series. Photograph: © Richard Mosse, Prix Pictet 2017

Prix Pictet 2016 shortlist turns the lens on space - in pictures Read more

The very air we breathe is filling up with toxins. For years, gases have burned through the ozone layer, exposing us to ultraviolet rays and affecting climate change. Airborne diseases – such as Zika, swine flu and bird flu – have multiplied and threatened to become global pandemics.

Great clouds of smog hover above our cities and airborne diseases multiply. Inhalation of toxic gases is said to reduce average lifespans by one to two years. Various estimates suggest that air pollution accounts for between half and two-thirds of all premature deaths in Asia, while anywhere between 10 and 20% of all worldwide deaths are attributable to the same cause.

Typhoons, hurricanes and cyclones are harbingers of disaster, yet the winds are also, for some, an important source of energy. The debate about the effectiveness of wind farms rages on. Protesters claim they are ineffective and even dangerous eyesores, while pro-campaigners trumpet the positive impact of these wind farms.

Facebook Twitter Pinterest Crammed in … a photograph of Hong Kong life from Benny Lam’s Trapped series. Photograph: © Courtesy of Benny Lam (photographs), Kwong Chi Kit and Dave Ho (concept), Prix Pictet 2017

Space itself – famously the final frontier – has not been colonised but has, instead, become a dumping ground to such an extent that scientists are now calling on nations to reduce the quantity of orbital junk they produce or risk inhibiting future space activity. And yet, as overpopulation and decreasing landmass become a conundrum for future generations, will outer space provide an inhabitable environment? Space exploration and research are continuing, with Nasa proposing to station a team of astronauts on the moon for a prolonged stay. There is even talk of space stations on Mars.

Twelve photographers were shortlisted for this year’s Prix Pictet award, on the theme of space. Each has made outstanding images that address the theme of space with originality and narrative power. Some, like Mandy Barker, create brilliant artificial worlds in which the plastic particles that are choking our oceans are presented as if they were plankton suspended in water drops. Scientific research has found that plankton ingest tiny plastic particles, mistaking them for food. Since they are at the base of the food chain, they are themselves a crucial source of nourishment for larger creatures. The potential impact on marine life and ultimately humankind is of deep concern.

The shortlisted artists follow radically different paths but often arrive at parallel conclusions. Richard Mosse and Sergey Ponomarev focus on the refugee and migration crisis now facing Europe. Mosse’s searing monochrome images of refugee camps and staging sites reduce individual refugees to an inhuman mass, while Ponomarev’s photographs show despairing human beings with nothing left to lose. They have somehow found the strength to undertake a perilous sea journey, in the promise of a better life, in the hope that a safe space awaits them. They exist in limbo, excluded from modern societies.

Facebook Twitter Pinterest Nothing left to lose … migrants arrive at the Greek island of Lesbos, in a shot by Sergey Ponomarev. Photograph: © Sergey Ponomarev, Prix Pictet 2017

Michael Wolf and Benny Lam explore those who have, at some personal cost, woven themselves into the social fabric of our cities. Lam focuses on the cramped living conditions of Hong Kong’s poorest citizens, for whom a single 40-square-foot room (the size of a toilet or balcony) is home.

Wolf ’s Japanese commuters are among the 3.64 million people who use Tokyo’s Shinjuku Station every day. Wolf pictures their faces rammed against the glass panes of a subway train. Clearly, this is no way to live. Yet these lives abide. And perhaps in this ability to carry on in adversity lies hope for us all. Hope that, despite the catastrophic damage that we have visited upon the natural world and upon the lives of our most vulnerable fellow citizens, it is not too late for us to reverse the damage.

The artists shortlisted have shone a light on the issues. We ignore them at our peril.

• The Prix Pictet: Space exhibition is at the V&A, London, 6-28 May. Kofi Annan will announce the winner tonight at a ceremony at the museum.