but also on socioeconomic and political ones. Security concerns arise from climate events that prove disruptive. Extreme climate events are sometimes, but not always, disruptive to social and political systems, and climate events that are not extreme can sometimes be very disruptive; the ultimate outcome depends on susceptibilities and reactions to harm. It is important to project the likelihoods of potentially disruptive climate events, but analyses restricted to this, whether globally or at finer scales, will often fail to provide sufficient information to those concerned with human, national, or international security. It is also necessary to consider socioeconomic and political conditions at levels from local to global.

The Picture Changes Over Time

All the elements in the conceptual framework change over time, and they change at various rates. Thus, to anticipate the risks of security concerns arising at any point in the future requires an analysis that examines all of the framework’s elements and their interrelationships in the intervening period. Socioeconomic and political conditions often change more rapidly than average climate or many environmental conditions, and this is likely to be the case over the coming decade. When this is the case, the rate of change in the risk of disruption from climate events may be more dependent on changes in the conditions affecting exposure and vulnerability, including actions taken to reduce susceptibility and prepare for disasters, than on changes in climate.

Changing Exposures to Coastal Storms and Floods

A simple example is the growing risk to human populations in coastal areas from storm surge and sea level rise. Climate and environmental change are exposing more land to these hazards, but in many regions rapid population growth and infrastructure development resulting from birth rates exceeding death rates, net migration, and economic development are putting people and property in harm’s way faster than climate and environmental change alone. For example, one recent scenario-based analysis estimated increases of population exposure to coastal flooding as a function of climate change and changes in social and economic conditions over the next 60 years in several countries. It concluded that exposure in India would increase from the present level of about 5 million people to about 28 million, with about 13 million of that increase attributed to socioeconomic change and about 10 million to the combination of climate change and land subsidence. In Côte d’Ivoire, Egypt, and Nigeria, almost all the projected increase in population exposure is due to socioeconomic change; in Japan,



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