摘要

Sedimentary paleotempestological studies have documented that tropical cyclone activity levels in the North Atlantic have been characterized by significant fluctuations since at least the mid Holocene, with activity regimes typically lasting from several centuries to %26gt; 2000 years. These activity-level estimates are based on site-specific hurricane strike histories derived from proxy records of overwash events attributed to landfalling major hurricanes. Here we present a 7000 year composite record from two adjacent wetland sites in coastal Belize, Central America that records both tropical cyclone-generated storm surges and large precipitation events. Although overall sensitivity appears to decrease over time, this record displays clear evidence of continuous oscillation between distinctly different activity regimes, with active and quiet periods each covering similar to 50% of the record. Active periods occur during similar to 200-600 BP, 1450-2600 BP, 3200-4200 BP, 4750-5450 BP, 5750-6050 BP, and 6700-6900 BP. This activity pattern does not match regional records from the northern Gulf of Mexico, the northern Caribbean or the Atlantic coast of the USA, thereby supporting the view that activity patterns are temporally variable throughout the North Atlantic, and that hyperactivity does not occur simultaneously across the entire basin.

  • 出版日期2013-2