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A global research agenda

The topic of environmental change, particularly climate change, and migration is exploding onto the global policy agenda. Yet little evidence-based research exists to inform sound decision making. To address the need for more sound empirical research and to identify how to carry forward a global research agenda, the UN University Institute for Environment and Human Security (UNU-EHS) together with the International Organization for Migration (IOM) and the UN Environment Programme (UNEP) brought together 35 experts in the fields of migration and the environment in April 2008. They assessed the current knowledge base and identify research gaps and priority areas for research, which fell within three main areas:

1. Measurement and identification: More work is needed to conceptualise and quantify migration responses to the impact of environmental change and degradation. The existing, speculative estimates about the potential scale of environmentally induced human displacement underline the fact that we know very little about how changes in the environment affect migration and that we lack the data and research necessary to move beyond such estimates. We do not understand well how slow-onset events, including desertification, sea-level rise and deforestation, affect migration within and between countries. Nor do we know much about how expected changes in migration patterns are likely to affect the environment. Policymakers lack the information necessary to prepare for, prevent or respond effectively to environmental migration.

While experts felt that policymaking would benefit from a differentiated definition of environmentally induced migration, a working definition such as the one proposed by IOM[1] was deemed helpful for the purpose of framing the debate and measuring the phenomenon. Long-term environmental degradation interacts with migration in complex ways that make it difficult to clearly attribute people’s reasons for moving and whether they are in fact environmentally induced migrants. An absolute number of environmental migrants, as often demanded by the media, is difficult to arrive at and current numbers are, at best, estimates.  

2. Interactions and linkages: The meeting explored the complex interactions of environmental change with economic and social factors that drive environmental migration. How are they linked? The links between migration and environmental change are multi-directional, making it necessary to examine other factors such as governance, poverty, lack of social cohesion and conflict. Environmental change may have a multiplier effect on other drivers of migration.

Who migrates, where and when? In the face of slow environmental change those who are able to move – those with money, social networks and alternative livelihoods – may tend to migrate independently. The vulnerable poor, those with no capacity to move when environments deteriorate, the very young and the elderly may be left behind or forced to resettle later. Gender and demographic structure also play a role in patterns of environmentally induced migration. While internal migration is likely to increase pressure on urban areas, international migration may become a more prominent feature of environmental migration as environmentally induced migrants draw on existing networks formed between source and destination countries.

Research and policy must make distinctions about the type of environmental stressor and the nature of human movement. Slow- and rapid-onset environmental situations will contribute to different migration patterns, ranging from temporal displacement and permanent displacement, to cyclical migration and permanent migration. Experts discussed identifying crisis tipping points or migration thresholds in the case of slow-onset environmental change.

What are the responses and how do people migrate? The tendency to migrate in the face of environmental stress may increase when temporary migration is already an established phenomenon. Migration should not be seen solely as a failure but also as a form of adaptation to environmental change. More investigation of possible positive effects of migration on the environment is needed.

3. Scenarios and policy: Migration needs to be discussed more within the context of adaptation strategies. For this to happen, policymakers need to better understand thresholds and critical tipping points. Other key policy areas include relocation and resettlement. Relocation has profound impacts on both displaced populations and receiving communities – but most policy currently focuses almost entirely on the process of the move. Looking at other forms of displacement and policy response can help shape appropriate policies.

A global research agenda and action plan

With agreement on the need for a global inter-disciplinary research programme to respond to these priority areas, the experts laid out four imperatives for further work on environmental migration:

  1. Systematic review of available research evidence on environmental migration. This baseline will highlight where new methods and approaches need to be developed, and lay the path for future coordinated work.
  2. A global multi-disciplinary research programme based on new in-depth field studies and using a common research design. The field studies will focus on those parts of the world currently, and expected to be, worst affected by environmental degradation and climate change.
  3. Information and knowledge management, using networks, databases and websites, to ensure that research findings and key policy developments are shared effectively between key stakeholders and to encourage exchange of experiences and good practice.
  4. Capacity-building projects to enhance data collection and use to ensure that countries likely to be most affected by environmental migration will have an adequate research base, training workshops for policymakers and best practices based on policy-oriented research.


To achieve human security in the face of expected climatic shifts, there must be careful multi-stakeholder involvement, particularly in resettlement and accelerated adaptation. Coordinated policy attention and action based on sound empirical evidence are needed today.


Koko Warner ( is Head of the Environmental Migration, Social Vulnerability, and Adaptation Section at UNU-EHS ( in Bonn, Germany. Frank Laczko ( is Head of Research and Publications at IOM (

For more details of discussions at the workshop, see

[1]Environmental migrants are persons or groups of persons who, for compelling reasons of sudden or progressive changes in the environment that adversely affect their lives or living conditions, are obliged to leave their habitual homes, or choose to do so, either temporarily or permanently, and who move either within their country or abroad.” Discussion Note: Migration and the Environment. IOM Council 94th Session 2007.


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