The Deadliest Atlantic Tropical Cyclones, 1492-1996

Conclusions

5. Conclusions

The areal distribution of the deaths based on Appendix 1 is shown in the following table; but, as described below, these totals indicate losses that are likely significantly lower than the actual losses.

Table 1: Areal distribution of deaths due to Atlantic tropical cyclones listed in Appendix 1. Totals are rounded.
Location	Fatalities
Greater Antilles	45,000 (29%)
Offshore Losses	35,000 (22%)
Lesser Antilles	35,000 (21%)
United States mainland (Galveston storm: 8,000)	25,000 (16%)
Mexico and Central America	20,000 (12%)
Elsewhere (Azores, Bahamas, Bermuda, Canada, Cape Verde Islands, South America, Ireland)	1,000 (<1%)

The disposition of the many casualties from shipwrecks near shore into offshore versus land losses is not certain.

It is interesting that over 90% of the offshore losses occurred more than 200 years ago (before 1790), as did all 12 offshore losses of more than 1,000 people. For the continental United States, the Galveston storm was responsible for about one-third of the deaths (using data in Appendix 1 only).

The areal totals indicate a large death toll across the region. They do not, however, adequately reflect the threat of the individual intense hurricane. We note that the five tropical cyclones at the top of Appendix 1 (1780 Great Hurricane, 1900 in Galveston, 1974 Fifi, 1930 in Dominican Republic, 1963 Flora) account for about one-third of all the deaths over the past 500 years in storms for which quantitative data on deaths has been found. In fact, the 10 deadliest storms, while representing less than 5% of the cases in Appendix 1 and less than 0.2% of all tropical cyclones since 1492, account for almost one-half of the deaths indicated in Appendix 1.

These statistics point to the tremendous repercussions that small track changes have had (and will have) on population centers at risk from a potentially pastdeadly storm. A shift of about 50 miles in the track of the 1900 Galveston hurricane could have meant far fewer deaths on that vulnerable island and (hence) overall. (This distance is comparable to the current average NHC 24-hour "across" track forecast error.) On the other hand, because of the growing population, there is an increasing number of highly susceptible regions which, only so far, have escaped such a catastrophic event (e.g., Sheets 1990). Damage statistics also illustrate this point. In 1992, Hurricane Andrew caused around $25 billion damage in South Florida (Rappaport 1993). An estimate indicates that a 20 mile northward shift of Andrew's track would have resulted in two to three times that much damage (Doig, 1992). Alternately, a southward shift of about 40 miles could have resulted in a negligible monetary loss to mainland Florida (but additional problems, including possible loss of life, for the less-populated Florida Keys).

The total number of deaths associated with Atlantic tropical cyclones of the past five centuries is likely much larger than implied by the data in Appendix 1. While it is a statistic that cannot be specified with confidence, a range for the total loss can be estimated. Appendix 1 provides a starting point and an underestimate of the total loss. Using the first number in the column on deaths for each case (except using 8,000 for the Galveston storm), the total number of deaths obtained from the table is around 160,000.

To this, we add several considerations.

Appendix 1

Many of the entries in Appendix 1 are minimum estimates (note the numerous ">" symbols).
We chose the first (largest) total in each case for Appendix 1 (except for the Galveston storm). In some cases, a smaller total could be more accurate.
Some storms with footnote "c" in Appendix 1 may not have been tropical cyclones.

Overall, consideration (a) probably dominates. We estimate that the total for Appendix 1 is around 200,000.

Appendix 2

The number of entries in Appendix 2 is smaller than in Appendix 1 and some of these cases probably did not result in 25 tropical cyclone deaths. These storms are probably responsible for an additional number of deaths that is considerably less than 200,000.

Other events

Greater than 25 deaths. We believe that most disasters responsible for very large losses are already documented in the Appendices, and that the remaining cases probably contribute less than 50,000.
Less than 25 deaths. Based on information in Monthly Weather Review, the number of deaths associated with this item in the past 50 years is about 575. If this data is representative of the entire study period, then these losses are less than 10,000.

Based on the above, we speculate that the number of deaths in Atlantic tropical cyclones from 1492-1994 is between one-third and one-half million. Factors contributing to the uncertainties noted above include relatively few references to losses in Mexico and Central America and incomplete information about losses from Spanish ships in the 1500's-1700's and to slaves and natives of the region. There are sources that could provide more definitive information, including old newspapers reviewed in a more systematic manner. This phase of the research is underway.