CRAMP: Hurricane Waves
Hurricane Waves are infrequent and unpredictable events in Hawai‘i, but have profound effects on coral reefs. Limited historical information exists on the location, size of waves and amount of reef damage on Hawaiian reefs caused by these waves (Dollar, 1982; Dollar and Tribble, 1993; Pfeffer and Tribble, 1985). Hurricanes are powerful storms that form over tropical waters whose effects include damaging surf and storm surge along coastlines, destructive winds (for hurricane, sustained winds of 74 mph or higher; for tropical storms, sustained winds of 39 to 73 mph), water spouts and tornadoes, and heavy rain and flooding. Most central Pacific hurricanes originate near Central America or southern Mexico. Many of these storms dissipate if they move northwestward over cooler water or encounter unfavorable atmospheric conditions. Of those that survive, most pass far to the south of Hawai‘i. Hurricane season begins in June and lasts through November in the Hawaiian Islands. Frequency of occurrence of tropical cyclones in the Central Pacific is quite variable. In 1978, for example, there were 13 tropical cyclones with three of them classified as hurricanes. The following year there were none. Hurricanes are divided into five categories according to wind speed ( Saffir - Simpson Scale).
The long-term record on frequency of hurricane impacts on Hawaiian reefs is obscure. Before 1950 damaging windstorms that struck Hawai‘i were not called hurricanes. Newspaper stories and government records, however, demonstrate that such storms have struck all islands in Hawai‘i since the beginning of recorded history. Documentation of these storms has increased greatly in recent decades. Since 1950 five hurricanes have caused serious damage in Hawai‘i.
Data track information from: Tom Schroeder, "Hawai‘i Hurricanes: Their History, Causes, and the Future." In Hawai‘i Coastal Hazard Planning Project. Office of State Planning, December 1993: 41-71. (Click for a larger view)
Hurricane Nina in 1957 produced record winds in Honolulu. Hurricane Dot (August 1959) caused 6 million dollars of property damage on Kaua‘i. Hurricane Iwa, in November of 1982 caused over 250 million dollars in damages on Kaua‘i and O‘ahu. On south Moloka‘i, waves damaged the docks at Kaunakakai. Hurricane Estelle produced very high surf on Hawai‘i and Maui and floods on O‘ahu in 1986. Hurricane Iniki caused extensive damage on Kaua‘i and Leeward O‘ahu in 1992. Hurricane Iniki was by far the most destructive storm to strike Hawai‘i in recorded history, with widespread wind and water damage exceeding 2.2 billion dollars. Most of the damage occurred on Kaua‘i and O‘ahu. The advent of meteorological satellites has revealed that hurricanes are a far more frequent in the central Pacific than previously suspected.
Hurricane Daniel was headed directly for Hawai‘i and building in strength in late July 2000, but suddenly dissipated into nothing more than a few rain showers before it made landfall. This serves as a good example of how satellites reveal that hurricanes are more common than previously known in the past. Image from Central Pacific Hurricane Center. (Click for a larger view)
In recent years, numerous hurricanes were detected that could have caused serious damage if they had passed closer to Hawai‘i. Hurricane Fernanda in 1993 and Hurricane Emilia in 1994 were the strongest on record to pass through the central Pacific. Tropical storms of less than hurricane strength can also cause extensive damage. For example, in August 1958, flooding rains and high winds from a storm that crossed Hawai‘i Island caused more than $500 thousand in damage.
Hurricanes that pass far offshore may cause extensive damage to reefs, but with little official notice due to lack of major property damage. For example, Hurricane Nina (November 1957) brought surf of 35 feet to Kaua‘i‘s southern coast. Waves from Hurricane Fico (July 1978) damaged homes and roads on the Big Island‘s Kau coast even though the storm itself was more than 400 miles to the southeast.
Dollar and Tribble, 1993
Pfeffer and Tribble, 1985
Last Update: 04/21/2008
By: Lea Hollingsworth
Hawai‘i Coral Reef Assessment & Monitoring Program
Hawai‘i Institute of Marine Biology
P.O. Box 1346
Kāne‘ohe, HI 96744