Estimating Oceanic Mixed-Layer Depth from Internal Wave Evolution Observed from Radarsat-1 SAR
نویسندگان
چکیده
ne Radarsat-1 SAR image acquired on 31 July 1998 was used to study internal wave characteristics off the northeastern coast of the United States. The image showed several trains of internal waves, with several wave packets in each train. By assuming that the local semidiurnal tide period is the generating source for these waves, and by measuring the distance between the wave packets, we were able to derive the group velocity of the internal waves from synthetic aperture radar (SAR) images directly. If we also assume that the ocean is a two-layer finite depth model, we can then derive the mixed-layer depth by matching the group velocity measured from the SAR image with that simulated by the model. Results show reasonably good agreement between in situ conductivity-temperature-depth data and expendable bathythermographic climatology measurements. (
منابع مشابه
Observation of hurricane-generated ocean swell refraction at the Gulf Stream north wall with the RADARSAT-1 synthetic aperture radar
In this study, we analyze the refraction of long oceanic waves at the Gulf Stream’s north wall off the Florida coast as observed in imagery obtained from the RADARSAT-1 synthetic aperture radar (SAR) during the passage of Hurricane Bonnie on August 25, 1998. The wave spectra are derived from RADARSAT-1 SAR images from both inside and outside the Gulf Stream. From the image spectra, we can deter...
متن کاملSimulation of entrainment near a density stratified layer: Laboratory experiment and LIDAR observation
In this paper a simple qualitative model of the growth of a mixed layer adjacent to a uniform layer with a stably stratified layer is presented. The depth variations of mixed layer can be estimated from direct measurements. The Entrainment of a stably stratified layer into a turbulent mixed layer in a confined region was studied in laboratory for different Richardson numbers. The internal waves...
متن کاملSea surface temperature signatures of oceanic internal waves in low winds
[1] In aerial surveys conducted during the Tropical Ocean–Global Atmosphere Coupled Ocean-Atmosphere Response Experiment and the low-wind component of the Coupled Boundary Layer Air-Sea Transfer (CBLAST-Low) oceanographic field programs, sea surface temperature (SST) variability at relatively short spatial scales (O(50 m) to O(1 km)) was observed to increase with decreasing wind speed. A unique...
متن کاملThree-dimensional of Coastal Front Reconstruction Using Radarsat-1 Sar Satellite Data
Natural phenomena that are imaged using remote sensing satellite data can be reconstructed in 3-D. This process can be accomplished either by active or passive methods. The active methods interfere with the reconstructed phenomena, either mechanically or radiometrically. The radiometric methods reconstruct the 3-D from the reflected or backscattered information about the specific objects or phe...
متن کاملInternal Wave Extraction in Sar Oceanic Surface Image Based on Stationary Wavelet Transform
An Internal Wave Feature Extraction (IWFE)algorithm based on Stationary Wavelet Transform (SWT) in SAR oceanic surface images is proposed. In this algorithm, SWT is applied to process SAR images and its coefficients are used to calculate the Wavelet Gradient Information (WGI). And the IWFE is obtained as edges by searching the calcaulated WGI’s maximum module value.. The morphological thinning ...
متن کامل