Observations of reflectance distribution around sunglint from a coastal ocean platform.

A scanning spectral photometer is deployed on a rigid coastal ocean platform to measure upwelling solar radiances from the sea surface at nine elevation angles spanning 150 degrees of azimuth. Measured radiance distributions at 500 nm wavelength have been compared with traditional model simulations employing the Cox and Munk distribution of wave slopes. The model captures the general features of the observed angular reflectance distributions, but: (a) the observed peak value of sunglint near the specular direction is larger than simulated, except for a very calm sea; the model-measurement differences increase with wind speed and are largest for low solar elevation; (b) the observed sunglint is wider than simulated. In contrast to some previous studies, our results do not show a clear dependence of the mean square sea-surface slope on stability (air-sea temperature difference).

[1]  W. Munk,et al.  Measurement of the Roughness of the Sea Surface from Photographs of the Sun’s Glitter , 1954 .

[2]  Yoram J. Kaufman,et al.  Satellite retrieval of aerosol absorption over the oceans using sunglint , 2002 .

[3]  Didier Tanré,et al.  Characterization of aerosols over ocean from POLDER/ADEOS‐1 , 1999 .

[4]  A. Lacis,et al.  Aerosol retrievals over the ocean by use of channels 1 and 2 AVHRR data: sensitivity analysis and preliminary results. , 1999, Applied optics.

[5]  K. Voss,et al.  Bidirectional reflectance of oceanic waters: A comparison of modeled and measured upward radiance fields , 1995 .

[6]  Yuguang Liu,et al.  Comparisons of scatterometer models for the AMI on ERS-1: the possibility of systematic azimuth angle biases of wind speed and direction , 1994, IEEE Trans. Geosci. Remote. Sens..

[7]  Xiao-Hai Yan,et al.  The Probability Density Function of Ocean Surface Slopes and Its Effects on Radar Backscatter , 1997 .

[8]  Xiao-Hai Yan,et al.  The Wind-Induced Wave Growth Rate and the Spectrum of the Gravity-Capillary Waves , 1995 .

[9]  C. Cox Statistics of the sea surface derived from sun glitter , 1954 .

[10]  J H Churnside,et al.  Scanning-laser glint measurements of sea-surface slope statistics. , 1997, Applied optics.

[11]  O. H. Shemdin,et al.  Measurement of high frequency waves using a wave follower , 1983 .

[12]  Menghua Wang Correction of the Sunglint Contamination on the SeaWiFS Aerosol Optical Thickness Retrievals , 2000 .

[13]  Paul A. Hwang,et al.  The dependence of sea surface slope on atmospheric stability and swell conditions , 1988 .

[14]  Brian Cairns,et al.  Case Studies of Aerosol Retrievals over the Ocean from Multiangle, Multispectral Photopolarimetric Remote Sensing Data , 2002 .

[15]  W. Liu,et al.  The Mean-Square Slope of Ocean Surface Waves and Its Effects on Radar Backscatter , 2000 .

[16]  Y. Kaufman,et al.  Retrieval of Black Carbon Absorption from Proposed Satellite Measurements Over the Ocean Glint , 2001 .

[17]  Larry D. Travis,et al.  Satellite retrieval of aerosol properties over the ocean using measurements of reflected sunlight: Effect of instrumental errors and aerosol absorption , 1997 .

[18]  R. Stull An Introduction to Boundary Layer Meteorology , 1988 .

[19]  Curtis D. Mobley,et al.  Albedos And Glitter Patterns Of A Wind-Roughened Sea Surface , 1986, Other Conferences.

[20]  Didier Tanré,et al.  Second Simulation of the Satellite Signal in the Solar Spectrum, 6S: an overview , 1997, IEEE Trans. Geosci. Remote. Sens..

[21]  M. Mishchenko,et al.  Retrieval of aerosol properties over the ocean using multispectral and multiangle Photopolarimetric measurements from the Research Scanning Polarimeter , 2001 .

[22]  H. L. Grant,et al.  A fast response surface-wave slope meter and measured wind-wave moments , 1977 .

[23]  M. Sancer Shadow-corrected electromagnetic scattering from a randomly rough surface , 1969 .

[24]  E. Hulburt Polarization of light at sea , 1934 .

[25]  Jin Wu,et al.  Sea‐Surface Slope and Equilibrium Wind‐Wave Spectra , 1972 .

[26]  Yoram J. Kaufman,et al.  Remote sensing of total precipitable water vapor in the near‐IR over ocean glint , 2000 .

[27]  S. Haimbach,et al.  Field trials of an optical scanner for studying sea-surface fine structures , 1985 .

[28]  Y. Trokhimovski Gravity-Capillary Wave Curvature Spectrum and Mean-Square Slope Retrieved from Microwave Radiometric Measurements (Coastal Ocean Probing Experiment) , 2000 .

[29]  Didier Tanré,et al.  Validation of the first algorithm applied for deriving the aerosol properties over the ocean using the POLDER/ADEOS measurements , 1999, IEEE Trans. Geosci. Remote. Sens..