Have Disaster Losses Increased Due to Anthropogenic Climate Change?

A nthropogenic climate change leads to more damage from weather disasters. This claim is made frequently in debates on the impacts of ongoing global warming. Although many other impacts and risks are associated with climate change, shifts in weather extremes are one of the most prominent anticipated impacts and of concern to many. The Intergovernmental Panel on Climate Change (IPCC) reported that the frequency of heavy rainfall and heat waves has increased, that the area affected by drought has increased in many regions, and that tropical cyclone activity has increased in the North Atlantic Ocean (Solomon et al. 2007, Table SPM.2). The recent global assessment report on natural disasters of the United Nations shows that the number of natural disasters, economic losses, and number of people affected are increasing at a rapid rate, faster than risk reduction can be achieved (UN-ISDR 2009). Governments are concerned about the potential economic implications of increasing risks, particularly the consequences for insurance systems for companies and households (GAO 2007; Ward et al. 2008; Botzen et al. 2010). There is clearly a need for analyses on the causes of increasing impacts from weather extremes as decision makers in government and companies plan for more frequent disasters and attempt to reduce exposure and risks. Also, better understanding of the relationship between anthropogenic climate change and disaster losses is needed to inform decisions on global climate change mitigation policy that is being negotiated and developed under the United Nations Framework Convention on Climate Change (UNFCCC). The expected impacts also indicate to what extent developed countries should financially compensate developing nations for the impacts of climate change and the costs of adaptation (Bouwer and Aerts 2006). Some major studies on the costs of climate change have been made over the course of past years (e.g., Pearce et al. 1996; Tol 2005; Stern 2007). The costs from weather extremes, however, are generally omitted or included in a very crude manner in the models of the costs of climate change (Tol 2002; HAVE DISASTER LOSSES INCREASED DUE TO ANTHROPOGENIC CLIMATE CHANGE?