SAN SALVADOR ISLAND AS A NATURAL LABORATORY TO STUDY IMPACTS OF COASTAL STORMS IN THE BAHAMAS
Although travel to the island and rapid assessment in the aftermath of storms can be hindered by infrastructure damage, our observations from Jan. 2000 revealed extensive sand beach erosion, dune scarping, overwash, generation of rock rubble, and damage to vegetation by Cat4 Hurricane Floyd (1999), which passed 20-30 nautical miles N-NE of the island. We documented recovery of beaches (2005-2010) after Sept. 2004 Hurricane Frances, and the impact of Oct. 2015 Hurricane Joaquin, both of which passed directly over the island as Cat3 storms. Along the south coast, Joaquin-generated waves overtopped 5m-high cliffs, causing erosion and inundation of the main road by limestone debris. Boulders up to 3 m in diameter were formed, and 1-3 ton boulders from prior storms moved up to 26 m inland. We conducted additional coastal boulder ridge surveys in Jan. 2012, 2013, and 2017 after Hurricanes Irene (Aug. 2011), Sandy (Oct. 2012), and Matthew (Oct. 2016), which passed W of San Salvador as Cat1-2 storms (Sept. 2019 Cat5 Hurricane Dorian passed too far N to impact the island). Recent (2019-2020) RFID (radio frequency identification) tagging of boulders and cobbles, together with high-resolution drone imaging, allowed us to begin assessing impact of winter storms and to enhance our database for future comparative analyses.
Lack of reliable weather and buoy data, and travel and fieldwork costs continue to represent challenges to ongoing work. We also strive to improve collaborations with the people and government of the Bahamas to minimize future human and infrastructure losses due to increasing frequency and intensity of storms coupled with rising sea levels.