According to the UNHCR, the United Nations (UN) refugee agency, more than 380,000 refugees and migrants have so far crossed the Mediterranean this year. We should not be surprised that so many people are willing to risk their lives in unseaworthy boats to reach Europe. They are fleeing war, violence and persecution. It is governance failure and poor management of the situation that has created the crisis.

Some researchers have suggested that there may be a link between climate change, the record drought that took place in Syria, the conflict and hence the refugee crisis in Europe. But it is very difficult to quantify what the contribution of climate change has been. What is clear is the potential for climate change to affect factors, such as the supply of food and water, which can drive migration.

Evidence of climate change causing an international refugee crisis?

Whether climate change can create a migrant and refugee crisis is up for debate. There is some evidence to suggest a link between climate, economic shocks and conflict. For example, the conflict in Syria has coincided with a record drought in the Fertile Crescent – a drought made up to three times more likely by climate change.

Historically, too, there are cases of climatic conditions increasing pressure on resources and ultimately leading to violence. It has been argued that historic persecution of Jewish communities in Europe often coincided with times of economic distress, and that rural uprisings in China increased during periods of higher drought frequency.

Archaeological evidence also indicates that climatic changes have led to important long-term shifts in human populations. For example, a 200-year drought in the Indus Valley led to the abandonment of the urban centres of the Harrapan Society, which is now in Pakistan.

However, the relationship between climate change and conflict is anything but straightforward. Studies of climate change-induced migration forecast large streams of migrants. But the underlying evidence is often weak.

Past episodes of climate change are not necessarily good guides to the future. Migration is dependent on a country’s socio-economic, institutional, and political characteristics.

For a given climate shock, less migration may occur compared to historical times because international borders and international laws limit migration today. Or migration could actually be greater today than past events would predict, perhaps because of lower transportation costs and the fact that information in more readily available.

People respond to climate change by migrating internally

Empirical evidence shows that people in developing countries are most ikely to respond to climatic change by migrating internally. The movement of people within a country’s own borders remains a time-honoured response to climate risk.

Research in six semi-arid countries – Burkina Faso, Senegal, Kenya, Tanzania, Pakistan and Tajikistan – as part of the PRISE (Pathways to Resilience in Semi-Arid Economies) project found many types of international migration that occur in response to climate risks. These include seasonal migration, medium-term, and permanent migration. There are climate migrants, economic migrants, political migrants and social migrants. Migrants can be forced or voluntary. And migration can differ in its outcome, being either productive or unproductive.

Crucially, the effect of climate change on migration depends on socio-economic, political, and institutional conditions. These conditions affect both vulnerability to climate change and how important climate change is in determining migration decisions.

For example, farmers are particularly affected by short-term climate shocks, such as floods and droughts, and long-term climate change.  Cases in Tanzania provide evidence of this, where vulnerability depends on people’s ability to adapt to change through the use of new crop varieties, for example. Access to credit, insurance and social safety nets also help.

Typically, migration decisions cannot be traced back to only one category of causes. Instead, different causes interact and form the basis for why people migrate. Important causes include economic, political and social factors. Environmental causes increase peoples’ economic incentives for migration, especially if they directly affect incomes.

One of the most important drivers of migration patterns across the world is the difference in income levels. If people expect that their income or living standards will increase by moving to another place, then they have a powerful incentive to do so. So, if climate change affects current or future incomes or living standards, it may affect decisions to migrate.

Public policy is needed to reduce the negative impacts of migration

Badly managed migration can force migrants to bear high economic, social and psychological costs. Public policy can help to encourage people to make positive migration choices and reduce the risks associated with migration.

The PRISE research makes a number of policy recommendations. Not least, it calls for clarity about the legal status of environmental migrants. Environmental migrants do not have a legal status comparable to a refugee’s legal status. A refugee’s legal status would, in theory, grant them legal protection to enter a country. An environmental migrant does not yet enjoy this legal security. The legal status of environmental migrants needs to be defined and the UN or UNHCR could lead efforts to achieve this.

The PRISE report also finds that there is a need for:

  • Clarity about alternative adaptation options: the full costs and benefits of migration choices need to be understood, including psychological and social costs.
  • Sufficient information: taking into consideration all types of costs, be they economic, social or psychological, is an integral part of making an informed choice about migration.
  • No credit constraints: credit constraints can force people to take the ‘wrong’ migration decision because migrants incur up-front costs (transportation costs, costs from not working, set up costs in destination locations).
  • Sufficient institutional quality: people may choose not to migrate even if they would benefit from migration if inadequate institutions reduce their incentives to migrate. E.g. Improved land tenure security and the ability to sell land or be confident of reclaiming it upon return.
  • Safeguards against distress migration: unplanned migration in response to climate stress causes people unnecessary hardship and economic loss. Conflict may also force people to choose inadequate locations regardless of their economic opportunities. These are signs of policy failure and maladaptation.
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