Optical methods for study of sea surface roughness and microscale turbulence

Charles S. Cox; Xin Zhang

doi:10.1117/12.279735

21 November 1997 Optical methods for study of sea surface roughness and microscale turbulence

Charles S. Cox, Xin Zhang

Proceedings Volume 3172, Optical Technology in Fluid, Thermal, and Combustion Flow III; (1997) https://doi.org/10.1117/12.279735
Event: Optical Science, Engineering and Instrumentation '97, 1997, San Diego, CA, United States

Abstract

The shape of the ocean surface on a millimeter scale controls the scattering of microwave radiation, hence the measurement of oceanic properties by remote sensing. In addition the micro-turbulence immediately adjacent to the sea surface brings about transfers of momentum, soluble gases such as CO₂, and heat or water vapor through the lowermost layers of air and the water immediately below. Although these processes are of vital importance to our understanding of the oceans and climate, they have not been adequately studied at sea. Recent developments of optical techniques have greatly simplified measurements of small scale fluid motions and have made them accessible to measurement from a small raft in the open sea. A contributing factor in these developments is the availability of high power, high efficiency visible light diode lasers and high resolution CCD arrays. Optical methods have the advantage that they do not influence the delicate motions of capillary waves at the sea surface, nor are they intrusive in the motions of small turbulent eddies. Our light source for study of turbulence below the water surface is a diode bar laser array. Light generated by the laser array is refracted into a fan shaped light sheet of approximate dimensions 50 by 20 by 2 mm to illuminate particles in the water. Sea water is sufficient transparent to this deep red light that particle tracking and particle image velocimetry can be carried out. The laser and a CCD camera in their water proof containers are so compact that they do not materially interfere with the water flow despite being mounted below the sea surface.

Citation Download Citation

Charles S. Cox and Xin Zhang "Optical methods for study of sea surface roughness and microscale turbulence", Proc. SPIE 3172, Optical Technology in Fluid, Thermal, and Combustion Flow III, (21 November 1997); https://doi.org/10.1117/12.279735

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available