Migration of people

Put simply, climate change will cause population movements by making certain parts of the world much less viable places to live; by causing food and water supplies to become more unreliable and increasing the frequency and severity of floods and storms. Same areas will be too hotter and drier —the proportion of land in constant drought expected to increase from 2 per cent to 10 per cent by 2050. On the other hand, changed rainfall patterns and a more intense hydrological cycle mean that extreme weather events such as droughts, storms and floods are expected to become increasingly frequent and severe.

Equally important though are the non-climate drivers. It is clear that many natural disasters are, at least in part, “man-made”. A natural hazard (such as an approaching storm) only becomes a “natural disaster” if a community is particularly vulnerable to its impacts. A tropical typhoon, for example, becomes a disaster if there is no earlywarning system, the houses are poorly built and people are unaware of what to do in
the event of a storm. A community’s vulnerability, then, is a function of its exposure to climatic conditions (such as a coastal location) and the community’s adaptive capacity (the capacity of a particular community to weather the worst of the storm and recover after it).

Different regions, countries and communities have very different adaptive capacities: pastoralist groups in the Sahel, for example, are socially, culturally and technically equipped to deal with a different range of natural hazards than, say, mountain dwellers in the Himalayas.42 National and individual wealth is one clear determinant of vulnerability – enabling better disaster risk reduction, disaster education and speedier responses. In the decade from 1994 to 2003 natural disasters in countries of high human development killed an average of 44 people per event, while disasters in countries of low human development killed an average of 300 people each.