SPECIAL REPORT: Preparing for 500 million environmental refugees

Posted: 1 December 2009

Author: Norman Myers and Jennifer Kent

Fourteen years ago, the writers published a major report on the emerging crisis of environmental refugees. Since then the issue has all but dropped from sight as other consequences of climate change have taken centre stage. Now, after two further years of research, the authors have prepared a new report, the essence of which is summarised here for the first time.

During the course of this century several hundred million people could well be driven to involuntary migration for largely environmental reasons. The most severe driver factors will be land degradation, drought, flooding and sea-level rise. Together these forces will put several billion people at risk and potentially generate more than 500 million refugees. In a number of countries, the consequences could be catastrophic.

Migrant, Ganges Delta
Migrant, Ganges Delta
In the Ganges Delta, living with varying water levels is a way of life. Migration, particularly towards coastal urban centres, has emerged as a coping mechanism when extreme events endanger life and livelihoods. With projected sea level rise, combined with the possibility of more intense flooding and storm surges, migration may become a necessity for many communities, at least for parts of the year. Photo © UNHCR
Climate change impacts are just beginning, and will steadily multiply and intensify. Present-day environmental crises such as drought, water scarcity, soil erosion and desertification will aggravate land-use conflicts and trigger further environmentally-induced migration. The most vulnerable areas are low lying coastal settlements, drylands and irrigated farmlands dependent on glacier snow melt. In all these regions, there will either be too much or too little water.

  • Low lying coastal settlements most at risk from sea-level rise and storm surges will be in countries such as Bangladesh, Vietnam, China, India, Pakistan, Thailand, Indonesia, the Philippines, Egypt, Mozambique, Senegal, Maldives and other Indian Ocean and Pacific islands.

  • Drylands subject to longer and more severe droughts are in countries such as Sudan, Somalia, Ethiopia, Eritrea, Chad, Mali, Senegal and Afghanistan.

  • Farming regions dependent on snowmelt from receding glaciers feeding river flow include the Ganges-Brahmaputra, Indus, Yangtze and Yellow Rivers.
New phenomenon

The world is facing an entirely new phenomenon. Never before have we witnessed such large numbers of people driven to abandon their homelands for basically environmental reasons. Already they come close to matching the population of Britain. Worse, they seem set to accelerate if only because the environmental drive factors will keep on expanding. Within the foreseeable future, and in the wake of the increased impacts of climate change, their totals could eventually exceed the combined populations of the United States and Western Europe.

While people will also be displaced in low-lying areas of developed countries, severe impacts will be concentrated in developing countries that are least able to mitigate and adapt to sea-level rise or the other problems arising from climate change. This surely ranks as one of the most pressing challenges of our time, even though it has largely remained a sleeper issue thus far. It holds major implications for development sectors such as health, agriculture, energy, water, human settlements, climate, security and whatever other factors comprise Sustainable Development.

Which refugees?

Despite its significance and the imperative of urgent action, the issue has received all too little attention from governments, international agencies, NGOs, the corporate community and the media. Since we published Environmental Exodus: An Emergent Crisis in the Global Arena (Climate Institute, Washington DC, 1995), there has been next to no substantive action in response. This appears to have been due to misunderstandings about the issue, and institutional inertia of many sorts -not least the very label "environmental refugees".

So just who are these environmental refugees? They are people who feel impelled to migrate because of chronic environmental factors. These include land degradation in the form of desertification and soil erosion and resource depletion in the form of deforestation (and the resulting lack of fuelwood), cropland and water shortages, and the acute impacts of drought, flooding, sea storms and tidal surges.

These factors - often aggravated by population pressures and widespread poverty - will be greatly increased by climate change. Migration occurs when families can no longer gain a secure livelihood in their homelands, and in their desperation feel they have no alternative but to seek refuge elsewhere, however hazardous the attempt. They abandon their homelands on a semi-permanent if not permanent basis, with little hope of foreseeable return.

In short, these migrants are people seeking refuge for primarily environmental reasons: hence their designation "environmental refugees." They must be differentiated from other kinds of migrants, notably economic opportunists seeking scope to better their lifestyles in lands beyond the horizon - a response quite different from those merely seeking to stay alive. The first are driven by environmental destitution, the second are drawn by economic opportunity.

Main hotspots

The main "hotspots" for such refugees include

  • inundations in the coastal zones of South, Southeast and East Asia, and in deltas such as those of the Nile and the Niger

  • regions prone to prolonged droughts in the drier sectors of Sub-Saharan Africa, especially the Sahel and the southern region - and also parts of Middle America

  • areas of outright desertification in several sectors of Sub-Saharan Africa and China.

All these have already generated large numbers of environmental refugees, and far greater numbers lie ahead. Large exoduses of destitute people could soon start to pose entirely new threats to international stability. This will especially be the case if the refugees feel they can best find sanctuary by heading for those developed countries which may appear to them to offer the best prospect of support. There would be some moral justification for this view, since these countries could rightly be seen as the principal sources of climate change.

Somali refugees in Kenya
Somali refugees in Kenya
More than 60,000 Somalis crossed into Kenya during the first two months of 2008. Photo: UNHCR/ E. Hockstein
However serious the present situation, it is surely a pale shadow of what awaits us when climate change impacts start to bite and today's tens of millions of environmental refugees become hundreds of millions. Those who consider this prognosis alarmist should recall that our environmental situation today is worse than it has ever been and is demonstrably deteriorating rapidly.

Whilst there are a number of success stories, these are currently too infrequent and too localised to make much difference to the big-picture dimensions of our environmental prospect. The same applies to population growth and widespread poverty, two important factors which often act in synergy with environmental problems

Scientific uncertainty We, as authors, agree that much uncertainty still attaches to calculations of numbers of environmental refugees, both present and prospective, due to the limited nature of available data. But absence of evidence of a problem does not constitute evidence of absence. As in other situations beset with uncertainty, it will be better for us to find we have been roughly right than precisely (and belatedly) wrong. The time for concerted action is now if we are to get on top of the problem before it gets on top of us.Environmental refugees, now and in the future, are an international problem demanding international solutions. Without widespread acknowledgement of their existence, there will be no international will or skill to tackle the problem. If we accept that environmental refugees already pose a significant policy challenge, in that any one or several factors operating at once are influencing the outcome, then current estimates indicate the problem could increase on exceptional scale if not addressed as part of global adaptation to climate change.

While environmental refugees undoubtedly represent a profound and fast-growing problem, there is also no doubt that they can become a spectacular opportunity - provided we, as a global community, bestir ourselves to pull the policy levers and support destitute people on a scale not known in human history. The challenge is unprecedented - so is our power to fix it.

Norman Myers and Jennifer Kent are both based in Oxford, U.K. Their 65,000-word research report entitled "Environmental Exodus in the 21st Century" will be available in summary form from or .