07/2008: Martin Parry


Martin Parry
Working Group on Impacts, Adaptation and Vulnerability,
Intergovernmental Panel on Climate Change (IPCC)


“Key issues in climate change, environmental degradation and forced migration”


Ü Eurasylum: Since its establishment in the late 1980s, the Intergovernmental Panel on Climate Change (IPCC) has stressed that one of the most critical effects of climate change and environmental degradation could be on forced migration. Frequent predictions estimate that up to 200 million people could be displaced by shoreline erosion, water shortages, coastal flooding and agricultural disruption by 2050. Can you guide us through the key issues related to the effects of climate change on population displacement?

Ü Martin Parry: There are three main areas of impacts from climate change which could affect migration, and which have been studied in some depth. These are impacts on water availability, food supply and flooding of coastal settlement.

In each of these areas, scientists have applied future projections of climate to temperature and rainfall conditions and then evaluated the implications of changes in weather for water, food and settlement.

Water availability is probably the most affected by climate change, with increases projected at higher latitudes and decreases in the tropics and subtropics. In general, currently moist areas of the world will get wetter, and currently arid areas will get drier, thus stressing populations in both directions (excess and deficit of water). It is the areas of projected increased aridity that are of most concern: especially a) north Africa (north of the Sahara), southern Africa, and the Middle East because these are regions where the response could be large scale outmigration; and b) Southern Europe and Western Australia, because these are important food-producing regions.

The scale of effect on people is estimated to be substantial. For a 1-2 deg C warming up to 1.5 billion people could be added to the category of being water stressed, that is, having insufficient water to meet average daily needs. For 2-3 deg C warming this could increase to over 2 billion. These are additional numbers specifically resulting from increases in aridity due to climate change.

Impacts on the agriculture sector are expected to come mainly from changes in water, largely reductions in water availability in mid and low-latitude regions leading to decreases in crop yield. Again, most affected are expected to be current semi-arid areas such as northern and southern Africa. The potentially farmed area in Africa could be reduced as much as a quarter, and yields within this area be reduced by 20 per cent over the coming two or three decades. In addition, this region is characterised by high levels of vulnerability and relatively low levels of technology, leading to relatively low capacity to adapt and thus high levels of impact. Globally, estimates of those numbers expected to be additionally at risk of hunger are in the order or 20-50 million for the 1-2 deg C of warming (and associated drying) expected over the next 40 to 50 years. In areas where food security is already low, climate change is therefore expected to have a strongly negative effect.

The third area where there has been study of impacts on livelihood, is coastal settlement and its exposure to flooding due to sea-level rise. The main areas of projected impact are the densely populated settlements of the Nile, Brahmaptra-Ganges, Mekong and the deltas of eastern China. The numbers at risk are large (in the hundreds of millions), but the numbers additionally at risk from flooding due to climate change are not as large as for water and food, being probably in the region of 1-5 million.

In all the foregoing estimates, the numbers of exposed people very much depends on the level of assumed adaptive response. But all these people are potential refugees.

Ü Eurasylum: According to some researchers (Myers and Kent, Castles, Black) there is still limited evidence that environmental degradation alone can cause large-scale migration. Additional contributing factors, such as ethnic tensions, ineffective government responses, economic problems, population growth or political struggle for land or power are often cited as playing a major part in population displacements apparently driven, primarily, by environmental degradation. Can you discuss any available evidence establishing the possible mono-causality of climate change for forced migration?

Ü Martin Parry: In the question above, I have been talking about potential refugees and asylum seekers due to climate change. How much migration actuality occurs will depend, inter alia, on: a) the amount of adaptation, b) the development pathway that countries follow in the next 20 years, and c) other multiple stresses on populations.

The IPCC concluded that some regions of the world are especially vulnerable to climate change: the people in Africa, small islands, and African-Asian megadeltas. In addition, it identified the following sectors as most at risk: water in semi-arid areas, farming in semi-arid areas, ecosystems in cold margins (eg the Arctic and tropical mountains � and the people dependent on these ecosystems).

In addition, the IPCC pointed out that there are people in all countries, even wealthy ones, who are especially at risk: these being the elderly, the young, the poor and the marginalised.

How much these potential impacts are translated into actual suffering and human migration will depend on the amount of adaptation, and this in turn depends on underlying capacity (technology, knowledge, social support systems, etc) that can be applied. Adaptive capacity is very dependent on wealth, so our assumptions about how the world develops over the next few decades can greatly affect our estimates of impact: If a country develops rapidly and substantial new wealth is created, then adaptive capacity will be enhanced; but not for all people if wealth generation is not spread equitably (as Hurricane Katrina showed in New Orleans).

And it is the case, as the question above suggests, that migration and asylum-seeking due to climate change are not likely to be easily separable from those due to other pressures on the resources that people need. So, where water becomes short due to over-use or due to decreases in rainfall, the effects may well be the same. More significantly, perhaps, is the likelihood that these kinds of different stresses tend to have a compounding effect, so people who are already placed in a precarious position due to a given trend (eg desertification, or reduced water availability due to a falling groundwater supplies) are likely to be more negatively affected by increasing drought risk due to climate change. That is why the IPCC concluded that climate change is likely to be most impacting in the context of multiple stresses.

Ü Eurasylum:: A recent IOM report prepared by Oli Brown has underlined that despite the serious development implications of large-scale forced climate migration there was still limited international interest or capacity to deal with this phenomenon. According to this report, policy responses to environment-led forced migration would require, first, that the definition of a refugee under current international law be expanded; second, that forced migration be incorporated into current domestic plans for climate change adaptation; and third that the OECD countries show some willingness to open new immigration channels for climate migrants. Can you comment on such policy responses or any other ones that may have been put forward by the IPCC ?

Ü Martin Parry: The IPCC does not make policy recommendations, and hence some of these questions have not been directly addressed by the IPCC. However, it is very reasonable to infer that, on the basis of what we currently know, the adaptation plans that countries are making under the UNFCCC should include migration plans. I am not really qualified to comment on the re-defining of refugee status. But, in addressing briefly the last point, I can say that the USA and Europe are likely to face increased pressure from environmental migration due to climate change, so the sooner this issue is addressed the better.