Abstract:
Part I: It is to be expected that in the future, measurements of pressure fluctuations beneath the ocean surface will provide basic data for solution of many practical problems on the state of the sea. As a result of the wartime impetus, several types of underwater pressure recorders (of similar instrumentation principles) were developed both in this country
and abroad. Essentially, the instrument consists of an underwater unit which electrically transmits pressure impulses near the sea bottom to a clockwork recorder installed
on the shore. The underwater pressure unit is adjusted for pressure fluctuations resulting
from surface waves within the spectrum band of periods set up by winds acting
on the sea surface. The resulting records may be scaled for height and period of the
pressure fluctuations over known time intervals. An accessory wave analyzer has been
constructed for rapid periodogram analysis of the pressure records.
This investigation is concerned with a comparative study of observed sea surface
waves and recorded sea bottom pressure fluctuations. It was undertaken for the purpose
of evaluating sea surface wave heights from sea bottom pressure recordings in the vicnity
of Woods Hole and Bermuda.
Part II: The results presented here comprise data on the state of the sea surface in the vicinity
of Woods Hole (off Cuttyhunk Island, Massachusetts) July 1946 to May 1947, and off
Bermuda, British West Indies, February 1947 to May 1947, obtained from analyses of
automatic wave recordings. At both locations measuring elements of the wave recording
instruments were located on the sea bottom (approximate depth 75 feet at Cuttyhunk
and 120 feet at Bermuda) and electrically connected to shore recorders several miles
away. The instrument operational schedules were continuous twenty minute recordings
every two hours at Bermuda and every six hours at Cuttyhunk.
