THE modern world has long thought of refugees in strictly political terms, victims in a world riven by competing ideologies. But as climate change continues unabated, there is a growing population of displaced men, women and children whose homes have been rendered unlivable thanks to a wide spectrum of environmental disasters.

Despite their numbers, and their need, most nations refuse to recognize their status.

The 1951 UN Convention Relating to the Status of Refugees defines a refugee as a person with a genuine fear of being persecuted for membership in a particular social group or class. The environmental refugee - not necessarily persecuted, yet necessarily forced to flee - falls outside this definition.

Where the forest used to be, torrential rains bring barren hills of mud down on villages. Crops wither in the parched earth. Animals die. Melting glaciers and a rising sea swallow islands and low-lying nations, flooding rice fields with salt water. Factories spew toxic chemicals into rivers and oceans, killing fish and the livelihood of generations. So people flee. Many become internally displaced, others cross any and all borders in order to survive.

Experts at last year's American Association for the Advancement of Science estimated their numbers would reach 50 million by 2020, due to factors such as agricultural disruption, deforestation, coastal flooding, shoreline erosion, industrial accidents and pollution. Others say the number will triple to 150 million by 2050.

'Environmental refugee'

Today, it is believed that the population of environmentally displaced has already far outstripped the number of political refugees worldwide, which, according to the United Nation High Commissioner on Refugees, is currently at around 10.2 million. Still, accurate statistics are hard to come by.

Because the term "environmental refugee" has not been officially recognized, many countries have not bothered to count them, especially if the population is internally displaced. Other countries consider them migrants, and therefore beyond the protection granted refugees.

Another factor obscuring the true scope of the population is the fact that their numbers can rise quite suddenly - such as after the Fukushima nuclear disaster last year, or Haiti's 2010 earthquake, which displaced more than 3 million people -which makes accounting for their number difficult, if not impossible.

In 1999 the International Red Cross put the number of those displaced by environmental disasters at 25 million. In 2009 the UN refugee agency estimated that number to be 36 million, 20 million of whom were listed as victims of climate change-related issues.

Two decades ago, noted ecologist Norman Myers predicted that humanity was slowly heading toward a "hidden crisis" in which ecosystems would fail to sustain their inhabitants, forcing people off the land to seek shelter elsewhere. After Hurricanes Katrina and Rita, however, the crisis became painfully obvious.

Displaced Americans

As the world watched in awe and horror while hundreds of thousands of displaced Americans scurried across the richest nation on Earth searching for new homes, it became clear that no matter how wealthy or powerful, no country is impervious.

Indeed, being displaced by natural disasters may very well become the central epic of the 21st century. Kiribati, the Maldives and Tuvalu are disappearing as we speak, as the sea level continues to rise. The World Bank estimates that with a 1 meter rise in sea level, Bangladesh - with a population of 140 million - would lose 17.5 percent of its land mass and along with it river bank erosion, salinity intrusion, flood, damage to infrastructures, crop failure, destruction of fisheries, and loss of biodiversity.

China, in particular, is a hot spot of environmental disasters as many of its places buckle under unsustainable development, giving rise to air pollution and toxic rivers.

As the number of the displaced by failing ecosystems increase, the work for their protection is failing behind. While a political refugee is given some modicum of protection, often those who fled their environmentally devastated homeland are seen as mere migrants. When President Obama granted temporary protected status to undocumented Haitians living in the United States in the aftermath of the earthquake in Haiti, it was a baby step in the right direction for human rights.

After all, repatriating them back to a living hell would be immoral at best, and at worst, a crime against humanity. But it is a small step toward addressing pressing needs and legal protection of this growing population.

Reforestation

Many more steps are needed. Policies toward addressing a solution involving the millions of climate refugees should also include addressing the issue of reforestation, and rehabilitating degraded land and soils, as well as addressing desalination of low coastal areas.

Those involved in man-made environmental devastations - illegal mining, toxic dumping, and oil exploration -that cause natives to flee should be held fully accountable in international courts and prosecuted to the fullest extent of the law and be held responsible for the resettlement and compensation of those they displaced. No doubt these efforts are more than challenging but they are the necessary steps in the right direction.

"One of the marks of a global civilization is the extent to which we begin to conceive of whole-system problems and whole-system responses to those problems," noted political scientist Walt Anderson in his book "All Connected Now." "Events occurring in one part of the world are viewed as a matter of concern for the whole world in general and lead to an attempt at collective solutions."

Whether humanity can move toward a global civilization will depend by and large on how it can act collectively deal with what's arguably the central issue of our time: climate change and resulting human displacement.

There's an old saying, "A rising tide lifts all boats." But in the age of melting glaciers, that tide is an ominous threat. The global age will not be as golden as some had predicted unless this dire challenge is met by whatever means necessary. For rising tides will not just send more refugees fleeing but, if ignored, could swallow humanity itself.

Andrew Lam is an editor with New America Media and the author of "Perfume Dreams: Reflections on the Vietnamese Diaspora" (Heyday Books, 2005) and "East Eats West: Writing in Two Hemispheres." His next book, "Birds of Paradise Lost," is due out in 2013.