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McKenzie, A. 2012. Beach Responses to Hurricane Impacts: A Case Study of Long Bay Beach, Negril, Jamaica. Caribbean Journal of Earth Science, Volume 43, 51-58. Available online: 2nd July 2012. © Geological Society of Jamaica. Beach Responses to Hurricane Impacts: A Case Study of Long Bay Beach, Negril, Jamaica A. MCKENZIE National Environment and Planning Agency, 10 Caledonia Avenue, Kingston 5, Jamaica [email protected] ABSTRACT. Over a three year period between hurricanes Michelle (2001) and Hurricane Ivan (2004) the Long Bay Beach, Negril Jamaica, was able to largely recover to its pre hurricane Michelle position. Between hurricanes Ivan (2004) and Wilma (2005) and hurricanes Wilma and Dean (2007) however, the Beach experienced a net loss of approximately five (5) meters. Overall the data suggest that the Beach requires a minimum of 3-4 years to recover to its pre- storm position following the near passage of a category 4 storm event. This Paper documents the erosion and recovery of Long Bay Beach, following storm events and proposes a beach recovery response time schedule which would be of interest to beach property owners and other economic users and stakeholders. Bench marks established in 2000 and beach profile data collected over a nine year period (2000-2008) provide an opportunity to study the effects of five (5) hurricanes (Mitch 1998, Michelle 2001, Ivan 2004, Wilma 2005, Dean 2007) on the level of beach erosion and to monitor post-storm recovery. Tropical storms and hurricanes, particularly late season hurricanes as demonstrated by Hurricanes Mitch, Michelle and Wilma pose, a serious threat to beaches on the south west coast of Jamaica including the Long Bay Beach, Negril. Beach property owners and beach managers in this area must therefore prepare and implement beach adaptation strategies as a counter to the impact of these storm events. Key words: beach, climate change, erosion, coastal vulnerability, hurricane, Jamaica, Negril. 1. INTRODUCTION heightened given the real or perceived increase in the numbers and intensity of tropical storms and The beaches of Jamaica are perhaps the Island’s hurricanes in the Caribbean Basin and the possible single most important natural resource. They are effect of climate change, in particular, sea level rise. the basis for much of the tourism industry, which is There is hardly any doubt that tropical storms Jamaica’s largest source of employment and second and hurricanes have played a significant role in the largest source of foreign exchange. There is a historical development of Jamaica’s coastline. The strong link between the quality of beaches and the effects of Hurricane Gilbert (1988) on Jamaican level of tourist activity. Tourism is one of the most beaches have been well documented (UNEP 1989). important economic sectors for Island states. For a Hendry (1982) made observations of the number of countries, such as Antigua and Barbuda, influence of Hurricane Allen in August 1980 and the Bahamas, Barbados, Cyprus, Grenada, Jamaica, Tropical Storm Arlene in May 1981 on the beaches St. Kitts and Nevis, tourist revenue makes up more at Negril. More recently approximately 2 km of the than 20 percent of the gross national product shoreline in Negril suffered from erosion as a result (Nurse, 2002). of the passage of Hurricane Mitch in 1998. Beaches also provide an important recreational Records of hurricane damage exist in the resource for the local residents; protect coastal archives of the Caribbean for over five centuries. lands from wave action, especially during The records over the past century show a wide band hurricanes; provide fish landing sites and are an of hurricane activity across the Caribbean aesthetically pleasing part of the environment. (UN-ECLAC 2002). In recent decades, beach loss has become a Cyclones cause storm surges and with elevated major problem and concern to Jamaica (Hendry, sea levels, these surges are predicted to be more 1985). This is partly because in some areas, coastal destructive, and even more so if cyclone intensity infrastructure and entire communities are increases due to climate change (Barnett, 2001; Van threatened by beach erosion. This concern has been Vuren et al., 2004). Recent studies suggest an 51 ROBINSON ET AL. – Beach erosion at Negril increase of 10–20 percent in the intensity of able to recover in a short period of time after an tropical cyclones under enhanced atmospheric extreme weather event. carbon dioxide conditions (IPCC 2007). Comparative observations by Hendry (1982) Six of the Atlantic most intense hurricanes have suggest that shoreline change over the previous 30 occurred over the last ten years. Four of these year period were negligible and examination of the (Mitch 1998, Ivan 2004, Wilma 2005, Dean 2007) aerial photo series from 1941 to 1990 for Long Bay have had a direct impact on Jamaica’s coastline and beach (Robinson et al., 2000) does not reveal any beaches. major change in the shoreline position during this This Paper seeks to use bench marks period. During the 1990s however, serious concerns established in 2000 and beach profile data collected began to be raised regarding the stability of the over a nine year period to study the effects of five beach. (5) hurricanes (Mitch 1998, Michelle 2001, Ivan Beach erosion is not a uniformly occurring 2004, Wilma 2005, Dean 2007) on the level of phenomenon along the entire 6.4 km length of the beach erosion and to monitor post-storm recovery beach at Long Bay. The study undertaken by the at Long Bay Negril, Jamaica . The erosion and Robinson (2000) found that sections of the Long recovery of the Long Bay Beach following the Bay beach were being affected to varying degrees. storm events is documented and a beach recovery The northern section of the Bay appears to be response time schedule is proposed. undergoing more severe, long-term erosion. Other sections appear to be periodically affected by 1.1. Setting significant storm related erosion, from which the The Long Bay Beach in Negril is part of a lagoon, beach eventually recovers. The southernmost beach and morass complex situated at the western sections of the beach appear to be generally stable. end of the island of Jamaica (Latitude 18° 16' - 18° The study indicated that the recovery time of the 23' N; Longitude 78° 18' - 78° 21' W; Figure 1). beach following storm event was more protracted Long Bay is a gently curving 6.4 km long beach, during the last 10 years when compared to the prior backed by a strip of sand with a relief of less than 20 years. 2 m. The shallow coastal shelf, has a general depth 1.3. Hurricanes of between 5 m and 12 m below sea level, and An average hurricane season in the Caribbean basin extends offshore for distances of up to 2 km from consists of some 10 tropical storms, of which six the beaches of Long Bay. The current direction in reach hurricane intensity (Rubiera, 2003). Six of the Long Bay is predominantly along shore. And top ten most intense hurricanes (Wilma 2005, Rita although the general direction of the currents is 2005, Katrina 2005, Mitch 1998, Dean 2007, Ivan from north to south, there are occasions in which 2004) occurred over the last twelve years. the flow changes. Of interest to Jamaica is the direction that the The non-skeletal grain composition of the beach is hurricanes take while on their path through the region. dominated by amorphous and crystalline grains, while Of particular interest is the path taken by late season the skeletal grains are characterized by abundant tropical systems that form in the central Caribbean foraminifera with smaller amounts of red algae, during mid to late October through to December and bivalves and Halimeda (Mitchell et al., 2002). Due to move north. Jamaica’s south-western beaches which are nutrient influx there has been a gradual replacement of normally protected from the regularly tracking Thalassia by fleshy algae. This coupled with the hurricanes and winter storms are now under these removal of sea grasses to facilitate the tourism circumstances exposed directly to the storm surges and industry is leading to smaller areas of sea grass cover. swell waves that these systems generate. Mitchell et al. (2002) anticipates that the loss in sea The data shows that from 1950-2007 grass area will lead to an overall reduction of approximately 79 storms systems came within 250 carbonate sediment production and the increased miles of Jamaica. Thirty or approximately 41% of likelihood of beach erosion. these storms can be categorized as late season 1.2. Previous work systems. Thirty-one systems attained hurricane Hendry (1982) undertook beach profile surveys status at their closest points to Jamaica. An analysis during the winter of 1980, coinciding with a time of the last 50 years show that there were at least six when 'northers' were noticeably frequent, periods of higher than normal storm activity all of generating rough seas at Negril which repeatedly which had storm erosion implications for Long Bay eroded the beach foreshore and created longshore Negril. These periods are; 1950-1952, 1961-1964, bars. Hendry (1982) described the Long Bay beach 1969-1971, 1079-1981, 1988-2001 and 2004-2007 as being stable in relation to wave activity, being (Figure 1). 52 ROBINSON ET AL. – Beach erosion at Negril The number of yearly tropical systems impacting Jamaica 1950 - 2007 6 5 4 3 2 Number of systems of Number 1 0 50-51 52-53 54-55 56-57 58-59 60-61 62-63 64-65 66-67 68-69 70-71 72-73 74-75 76-77 78-79 80-81 82-83 84-85 86-87 88-89 90-91 92-93 94-95 96-97 98-99 00-01 .02-03 .04-05 .06-07 Years Figure 1.