Sir

Another El Niño ‘event of the century’ has come and gone, and with it a wide variety of estimates of how much damage the world has incurred, ranging from US$14 billion to $69 billion1,2,3. Damage from all natural disasters in 1998 alone is believed to have cost some $93 billion4. Of greater concern than this lack of accuracy is a general tendency to describe impacts through a few global totals.

By aggregating impacts into a single estimate, much of the knowledge of and insight into the human-climate interface is lost. The environment does not affect us in simple, one-number packages. Only recently have we begun to measure quantitatively the varied losses and benefits (impacts) associated with climate variability, and these estimates have yet to be referenced to a baseline of impacts occurring in ‘normal’ years5.

Regional variations in reported damages, for example, do not inherently represent the reality of losses. Burton et al.6 note that biases exist “toward overestimating losses from industrialized countries and underestimating losses in developing countries or in areas remote from centers of government and mass media”. It is not easy to attribute and distinguish between losses associated with climate variability and maintenance costs. Although biases and uncertainties do exist, other factors need to be accounted for, for example the use of a prejudiced vocabulary to describe losses. Many estimators are unfortunately tempted to represent a globally perceived value rather than inter-regional functionality, for example. A thatched house may not fetch a global market value, but its loss during a flood is nonetheless an impediment to livelihood maintenance or to development.

Climate impacts are also largely a function of perception and scale. What is devastating to an individual is not likely to register on an international scale, except in extreme calamities. The incentives, disincentives and cultural preferences of an affected area often guide this perception of impact, which influences the reporting and visibility of climate events. It is likely that incentives such as ‘relief aid’ have increased the number of reported events. There are many other complex variables that need to be taken into account.

Not all impacts associated with climate variability are disastrous or even negative. To better understand the interaction between humans and climate, the popular vocabulary used to describe and record impacts of climate variability must move beyond deaths and dollar losses.