Effects of typhoon pamela on the coral reefs of Guam

Abstract

Guam, the southernmost island of the Mariana Islands, is likely to encounter a significant typhoon every seven years. During the last thirty years two typhoons have passed directly over Guam—Karen (11 November 1962) and Pamela (21 May 1976). Pamela had maximum winds of 120 kt (145 estimated), minimum sea level pressure of 930 mb, a speed of movement at 7 kt, a diameter of 20 nautical miles, and 33 inches of rainfall during the typhoon passage. The typhoon had its greatest effect along the shoreline where erosion removed many bands of beach deposits and where shoreline vegetation was defoliated. Relatively little damage occurred along the adjacent reef-flat platforms and reef margins. Some unconsolidated materials were shifted. The growing tips of some foliaceous corals fragmented. On the reef front a number of corals were overturned by the storm waves.