cost is that a climatic disaster aecting at least half a percent of a country's population, which in the whole sample period occurs once every four years, reduces real GDP per capita in 0.6 percent. Therefore, the increase in the incidence of these disasters observed in the data can entail non-trivial macroeconomic costs. For instance, with the average incidence post-1990 of one climatic disaster every three years instead, these disasters would reduce GDP per-capita in 2 percent over a decade.

The ndings also indicate that, historically, ows of ocial development assistance (ODA) do not importantly attenuate the output consequences of climatic disasters. Explicitly considering ODA in the model only reduces the output impact of climatic disasters from 0.77 to 0.63 percent of per capita GDP, and this reduction is not statistically signicant.

Among climatic disasters, droughts have the largest average impact, with cumulative losses of 1 percent of GDP per capita. Extreme temperatures also have a large average impact of 5 percent of GDP per capita, but results for this type of climatic disaster are based only on a sample of 12 countries. Other types of climatic disasters, such as windstorms (e.g. hurricanes and cyclones) and oods do not have a signicant impact when looking at the broad set of countries aected by any type of climatic disaster.

Across broad disaster's categories, small states are not signicantly more aected than larger countries. However, wind storms have a larger estimated impact on small states than other countries. Among small states, windstorms typically result in a 3 percent decline in per capita GDP, while they have virtually no impact on larger states.

Output in low-income countries responds more strongly to climatic disasters. Among these countries, a climatic disaster results in a 1 percent decline in per-capita GDP that is also statistically signicant at the 10 percent level during the initial years. In contrast, among middle and highincome countries, climatic disasters result in output losses of 0.5 and 0.25 percent, respectively. This larger response of low-income countries to climatic disasters is mainly due to the large output impact of droughts on this group, which reaches 2 percent of per capita GDP. In contrast, there is no signicant response to any type of disaster (climatic and other) among middle and high income countries.

The level of external debt has no relation to the impact of any type of disasters. Output losses for climatic disasters are almost identical for countries with low, medium, and high initial levels of debt. Distinguishing among dierent types of climatic disasters (droughts, extreme temperatures, oods, and windstorms) does not change this conclusion; for no type of climatic (and non-climatic) disaster there is a clearly dierential response among more indebted countries.

This paper contributes to a long literature that has aims to estimate the economic consequences of natural disasters. A large part of this literature relies on simple correlations arising from a limited number of case studies (see for example Albala-Bertrand (1993) and Otero and Marti (1995)). This approach permits focusing on the details of a particular event, but cannot isolate the impact of a disaster because, by construction, cannot control for other simultaneous shocks. For instance, disasters may be followed by aid ows that attenuate their macroeconomic consequences. Also, the limited number of cases typically analyzed (26 cases in Albala-Bertrand (1993)) also casts doubts on 2