Accession Number:

ADA458547

Title:

Quantifying Hurricane Wind Speed with Undersea Sound

Descriptive Note:

Docotral thesis

Corporate Author:

MASSACHUSETTS INST OF TECH CAMBRIDGE

Personal Author(s):

Report Date:

2006-06-01

Pagination or Media Count:

172.0

Abstract:

Hurricanes are one of the most destructive natural disasters known to man. While current satellite technology has made it possible to effectively detect and track hurricanes, expensive hurricane-hunting aircraft are required to accurately classify their destructive power. Here we show that passive undersea acoustic techniques may provide a promising tool for accurately quantifying the destructive power of a hurricane. It is well known that the crashing of wind-driven waves generates underwater noise in the 10 Hz to 10kHz range. Theoretical and empirical evidence are combined to show that underwater acoustic sensing techniques may be valuable for measuring the wind speed in a hurricane. Acoustic measurements of the underwater noise generated by hurricane Gert are correlated with meteorological data from reconnaissance aircraft and satellites to show that underwater noise intensity between 10 and 50 Hz is approximately proportional to the cube of the local wind speed. It has also long been known that hurricanes generate microseisms in the 0.1 to 0.6 Hz frequency range through the non-linear interaction of ocean surface waves. Here we model the microseisms generated by the spatially inhomogeneous waves of a hurricane, using the non-linear wave equation, and compare these estimates with seismic measurements.

Subject Categories:

  • Patrol and Reconnaissance Aircraft
  • Meteorology
  • Physical and Dynamic Oceanography
  • Optics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE