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Title: Airborne Measurements of Surface Wind and Slope Statistics over the Ocean
As reported in 1954, more than a half century ago, C. Cox and W. Munk developed an empirical model of the slope distribution of ocean surface waves that has been widely used ever since to model the optical properties of the sea surface and is of particular importance to the satellite remote sensing community. In that work, the reflectance of sunlight was photographed from a Boeing B-17G bomber and was then analyzed. In this paper, surface slope statistics are investigated from airborne scanning topographic lidar data collected during a series of field experiments off the coast of California and in the Gulf of Mexico, over a broad range of environmental conditions, with wind speeds ranging from approximately 2 to 13 m s −1 . Unlike the reflectance-based approach of Cox and Munk, the slope distribution is computed by counting laser glints produced by specular reflections as the lidar is scanned over the surface of the ocean. We find good agreement with their measurements for the mean-square slope and with more recent (2006) results from Bréon and Henriot that were based on satellite remote sensing. Significant discrepancies for the higher-order statistics are found and discussed. We also demonstrate here that airborne scanning lidar technology offers a viable means of remotely estimating surface wind speed and momentum flux.  more » « less
Award ID(s):
1634289
PAR ID:
10130717
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
Journal of Physical Oceanography
Volume:
49
Issue:
11
ISSN:
0022-3670
Page Range / eLocation ID:
2799 to 2814
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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