# **2.2.Hurricane damage frequency**

Hurricanes cause the most devasting disasters in the Caribbean and they have shaped the region’s history and will continue to shape its future. The movement of every tropical cyclic storm is characterized by extreme winds, storm surges, and exceptional levels of rainfall, which may cause flooding (HendersonSellers et al. 1998). Although the official hurricane season in the Greater Caribbean region begins on June 1 and lasts through the end of November, atmospheric conditions in the Atlantic Basin mean that approximately 80 percent of tropical storms and hurricanes form in a 45-day window from mid-August to late September.<sup>11</sup> The number and strength of Caribbean storms vary greatly from year to year, which makes detecting trends in the frequency or intensity of hurricanes over time a challenge. In the last 20 years, the islands in the region have faced storms from low to high intensity, classified in four types by wind speed, as determined by the Saffir-Simpson Hurricane Wind Scale:

- Tropical depression: cyclone with maximum sustained winds of 61 kph or less (Category 0)<sup>12</sup>

- Tropical storm: winds of 62–118 kph (Category 0)

- Hurricane: winds between 119 kph (Category 1) and 177 kph (Category 2)

- Major hurricane: winds of 178–208 kph (Category 3), 209–251 kph (Category 4), and 252 kph or higher (Category 5).

During our sample period of 2000–12, 146 hurricanes (Categories 1–5) and 196 tropical cyclones were reported in the Caribbean region. Figure 2 shows that Cuba, The Bahamas, Haiti, and the Dominican Republic were most affected by hurricanes, with more than 40 episodes in that period. Cuba and The Bahamas were affected by major (Category 3) hurricanes.<sup>13</sup> By contrast, southern areas like the islands of Aruba, Martinique, and Dominica are rarely affected by major hurricanes because they tend to travel away from the equator.

The Dow Jones Island Index ranked Curaçao as the Caribbean island least likely to be hit by hurricanes, followed by Bonaire, Cayman Islands, Barbados, and Aruba. Other Western Caribbean islands are also less likely to be affected by hurricanes than Eastern Caribbean spots like the British Virgin Islands and Puerto Rico. Dominica, Montserrat, and Trinidad and Tobago are among the least affected islands, with fewer than 10 episodes of hurricanes in the 12-year study period. Tropical depressions and storms—which are not hurricanes and therefore classed as Category 0—occur frequently and at any time during the Atlantic Ocean hurricane season. Curiously, the countries most impacted by these are Dominica and Trinidad and Tobago, which presented fewer impacts by hurricanes, and Guadeloupe, with around 13 episodes during 2000–12, followed by Barbados and Bonaire, Sint Eustatius, and Saba, with 12 episodes.<sup>14</sup> Some Caribbean islands are subjected to higher levels of wind speed more frequently than others. Over time, this has resulted in variations in building vulnerability across the region, as each country adopts or develops its own building codes and construction practices, reflecting its historical storm experience and

> 11 For more information about the peak of the hurricane season, see https://www.noaa.gov/stories/peak-of- <u>hurricane-season-why-now</u>

> 12 According to NOAA, a tropical cyclone is a rotating, organized system of clouds and thunderstorms that originates over tropical or subtropical waters and has a closed low-level circulation. Tropical cyclones rotate counterclockwise in the Northern Hemisphere.

> 13 Annex 2 shows the tendency of the damage index by Category 3 hurricanes by Caribbean country and territory. 14 For further detail, see Annex 3.

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