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TRANSACTIONS OF THE ROYAL SOCIETY OF TROPICAL MEDICINE AND HYGIENE (2003) 97, 139-140

Climate change and tropical disease

Climate change, conflict and health

E g b e r t Sondorp and Preeti Patel Health Policy Unit, London School of Hygiene and Tropical Medicine, London, U K

Abstract Both conflict and climate change may produce serious negative health consequences. However , there is insufficient evidence that climate change, e.g. through environmental degradation or fresh water shortages, leads to conflict as is often claimed. Also, current theory on causes of conflict would refute this hypothesis.

Keywords: climate change, conflict

Irrespective of their cause, wars are 'no t healthy for children and other living things' (Garfield & Neugut , 1991). A striking example is the ongoing war in the Democra t ic Republic of the Congo, hardly noticed by the outside world, where millions of people continue to die. A recent survey revealed the excess deaths of 2.5 million people over a 32-month period, of which 86% were due to disease and malnutr i t ion as a consequence of the war and 14% directly due to acts of violence (Roberts, 2001). T h e causes of today's 'modern wars' ,

Address for correspondence: Dr Egbert Sondorp, Health Pol- icy Unit, London School of Hygiene and Tropical Medicine, Keppel Street, London WC 1E 7HT, UK, e-mail egbert.sondorp@lshtm.ac.uk

which increasingly affect civilians, are often poorly understood. There is a growing body of multidisciplin- dry literature that tries to explain more precisely the origin and continuat ion of such modern wars. Under - lying this is the hope that, by better understanding of the causes of wars, preventive measures may become feasible. For instance, Paul Collier and colleagues at the Wor ld Bank have produced extensive statistical evidence to support economic causes of intrastate war (Collier, 2000). Others, however, have serious doubts about the validity of this kind of work (Cramer, 2002). Many other factors have been ment ioned as causes of war, summarized by Stewart as 'bad ' governance; poli- tical, economic and social inequalities; extreme poverty and despair; economic stagnation and endemic corrup-

140 CLIMATE CHANGE AND TROPICAL DISEASE

tion; poor and run-down state services; high unem- ployment; environmental degradation; and individual (economic) incentives to fight (Stewart, 2002). This list includes environmental degradation and conflict, which is often cited elsewhere as well (Homer-Dixon, 1994). However, since one of the conclusions derived from the literature on this subject is that there is almost never a single, straightforward cause that can be identified as the root cause of war, it is difficult to prove the link between ecological change and conflict. Most leading theories on the causes of conflict see ecological reasons as peripheral. Indeed they may accelerate or exacerbate a conflict but they are not usually seen to be the root cause.

There is wide agreement among climatologists glob- ally that human-induced climate change is now under way (Albritton et al., 2001). Global climate change is one of the various large-scale, unprecedented environ- mental perturbations occurring in today's world (McMichael & Woodruff, 2002). These environmental changes reflect the rapid increase in human domination of the biosphere as human numbers increase and eco- nomic activities intensify. Climate change, strato- spheric ozone depletion, loss of biodiversity, worldwide land degradation, fresh water depletion, disruption of elemental nitrogen and sulphur cycles, and global dis- semination of persistent organic pollutants have enor- mous potential consequences for the sustainability of ecological systems, food production, economic activ- ities and the health of human populations (Patz & Kovats, 2002). One of the ways in which climate change might affect health is that of war. It has been postulated, for instance, that land degradation or fresh water decline induced by climate change may lead to conflict and therefore also to serious consequences for the health of affected populations (Ahem & McMi- chael, 2002). In particular, concerning the latter issue of water shortages, there are quite vivid descriptions of pending 'Water Wars' (Shiva, 2002).

Although there are many good reasons to fear the consequences of climate change and its impact on human health, some care needs to be taken in using possible climate change-induced conflicts in the de- bates and advocacy stressing the importance of meas- ures to curb climate change. There is very little evidence that climate change-induced conflict actually exists and, if it does, it may be marginal. The link between environmental degradation and conflict is highly complex and may be, at best, a contributory factor amongst a range of co-factors that lead to wars. The risk of water wars, already predicted today, would increase if climate change leads to fresh water decline. However, there is again little evidence to support the claim that water shortages may lead to conflict. On the contrary, studies of conflicts over water show that they are the exception rather than the rule, and that a large number of treaties and agreements over shared waters exist. The Nile Basin Initiative, for example, estab- lished in 1998, represents a major success for regional integration and cooperation between previously belli- gerent states (ODI, 2002).

Both conflict and climate change have the potential to produce serious negative consequences on the health

of populations in affected areas. The 2 factors may become linked and mutually reinforcing under certain conditions. However, for the time being there is very little to prove that such a link exists or is of substantial importance. Some care, therefore, will have to be taken when introducing this link into the debate on the need to address the causes of climate change. What conflict and climate change have in common, however, is the need for a much improved global governance system to really address the underlying causes of both phenom- ena.

Acknowledgements Egbert Sondorp is supported by the Evidence-Based Huma-

nitarian Aid Project, funded by the Andrew W. Mellon Foun- dation.

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Received 20 January 2003; accepted for publication 29 January 2003