Amid the xenophobic and hostile debate that hangs like a dark cloud over the treatment of refugees and asylum seekers arriving at British shores comes this timely exhibition. It is a welcome exposé of the intense human suffering such people face in other corners of the world on fleeing their homes, often within the very conflict zones that fuel the global migration phenomenon. And as photographer Sebastião Salgado so aptly notes, “It is a disturbing story.”

A Brazilian, who fled to Europe to escape military rule in 1969, Salgado has spent the past few years documenting the lives of populations on the move throughout Asia, Africa, central Europe, and Latin America. His aim: to provoke debate on the human condition and the relentless cycle of displacement and migration, and to ensure that these stateless people are acknowledged and respected.

The underlying theme of many of these images is consistently disturbing and often brutal, despite their artistic quality. Scenes of Rwandan refugee camps in Zaire, 1994—after a genocide that saw the upheaval of hundreds of thousands of people to neighbouring countries—portray images of squalor, death, neglect, and hopelessness. One image shows a sick man, wide eyed with pain, waiting for free treatment in a temporary Médecins Sans Frontières field hospital in Katale; another, a man dying of cholera face down naked on a dirty floor surrounded by a crowd of onlookers. Grubby, hungry children stare into the lens with blank expressionless faces that say they have seen it all. You are left reeling, overwhelmed with anger that such misery is so ubiquitous, so incomprehensively large scale, and so often tolerated and even ignored by those of us who will never experience anything like it.

I found Salgado's images of Africa particularly depressing and in some instances almost too hideous, and too removed from my own life, to comprehend. Salgado has anticipated such a reaction, perhaps, devoting part of the exhibition to thought provoking images that document the lives of migrants entering the more developed world. He thereby brings the migration issue to our own doorstep.

Fleeing from war and repression, or to escape a life of abject poverty and limited opportunity, many of those migrants photographed in detention and deportation centres in Malaga, Spain, risk everything to cross the Straits of Gibraltar at night in tiny motorboats from Morocco. Many of them don't make it alive. Those that do face an uncertain future in the face of growing racism and hostility throughout a rich Western world bent on protecting its own interests.

A waiter from El Salvador in a Los Angeles restaurant, a Pakistani shopkeeper in the north of England—they surely deserve our respect, not relentless name calling as scroungers and terrorists. Indeed, such ongoing hostility seems so particularly wrong and ill informed when contrasted against Salgado's images of resilience and courage.

The nature of modern conflicts across the globe ensures that the majority of casualties are civilians, mostly women and children. Thus global displacement looks set to characterise this century as it did the last. As the aid community now braces itself for an increase in internally displaced people and refugees attempting to cross the Iraqi border into Turkey, Iran, Syria, and Jordan as the bombs drop on Iraq, you are left wondering whether there will ever be a way out of the cycle of human despair this exhibition encompasses. How long can we remain as informed spectators on the sideline watching such tragedy unfold before our eyes?