A RECORD OF VARIABILITY--HURRICANE ACTIVITY IN THE BAHAMAS, THE GREATER ANTILLES, MESOAMERICA, AND NORTHERN SOUTH AMERICA OVER THE LAST 2000 YEARS (Invited Presentation)

Hurricane activity has varied throughout the Caribbean and nearby regions throughout the past 2000 years. We present a high resolution synthesis of hurricane records, including new data from lake cores collected from San Salvador Island and Eleuthera Island in the Bahamas. Our synthesis shows that hurricane frequency varied temporally and geographically throughout the study area during this time period. Atmospheric and oceanic phenomena such as the El Niño Southern Oscillation (ENSO), the Intertropical Convergence Zone (ITCZ), the North Atlantic Oscillation (NAO) and the Caribbean Low Level Jet (CLLJ) have driven hurricane patterns over the last two millennia.

In the Caribbean and Western Atlantic, the Hurricane Hyperactivity period ended abruptly around 1300 years before present. In the Bahamas, prior to 1300, numerous strong storms struck the Caribbean and western Atlantic at a relatively high frequency. After 1300, tropical cyclone (TC) frequency dropped. These general trends are further divided into short, alternating periods of high- and low-hurricane frequency which are geographically heterogeneous. Within the Bahamas, records from Eleuthera and Abaco show synchronous periods of high and low tropical cyclone activity since 2000 YBP. Increased tropical cyclone activity has been linked to increased moisture in Mesoamerica but the relationship between hurricane activity and precipitation is variable in the Bahamas. There are periods of high hurricane activity and dry conditions (prior to 1300 YBP), but also reduced hurricane activity and relatively wetter conditions (~1300 YBP-400 YBP). After 850 YBP, the central Bahamas lakes record a continuous relatively wet climate. During times in which increased moisture but decreased tropical cyclone activity is recorded, it is likely that NAO, ENSO and CLLJ are the dominant drivers of precipitation in the region. Complex interactions between atmospheric and oceanic phenomena such as NAO, ENSO, and CLLJ lead to heterogeneous hurricane patterns temporally and geographically in the study area, even during globally expressed climate events such as the MCO and LIA.