Evidence and quantification of the correlation between radar backscatter and ocean colour supported by simultaneously acquired in situ sea truth

[1] Near simultaneously (within 2 hours) acquired ERS-2 Synthetic Aperture Radar (SAR) and Sea-viewing Wide Field-of-view Scanner (SeaWiFS) data over an upwelling region shows remarkable similarity in feature's location, scale, and boundary. Under uniform wind and sea states, reduction of Normalised Radar Cross Section (NRCS) from SAR is found highly correlated with the increase of SeaWiFS Chlorophyll-a (Chl-a) concentration. Typically, 1 mg/m3 of chlorophyll-a is correspondent with a 5 dB reduction of NRCS. This relationship is supported by simultaneously collected in situ sea truth measurements. This work provides a direct evidence and exceptional quantification of the relationship between radar backscatter and ocean colour that has long been speculated.

[1]  P. Clemente-Colon.  Evolution of upwelling-associated biological features in the Middle Atlantic Bight as captured by SAR, SST, and ocean color sensors , 2001, IGARSS 2001. Scanning the Present and Resolving the Future. Proceedings. IEEE 2001 International Geoscience and Remote Sensing Symposium (Cat. No.01CH37217).

[2]  G. Gong,et al.  Effect of the Kuroshio intrusion on the chlorophyll distribution in the southern East China Sea during spring 1993 , 1997 .

[3]  Kon‐Kee Liu,et al.  An assessment of the effect of sea surface surfactant on global atmosphere-ocean CO2 flux , 2003 .

[4]  W. Asher.  The Sea Surface and Global Change: The sea-surface microlayer and its effect on global air–sea gas transfer , 1997 .

[5]  Ola M. Johannessen,et al.  Satellite detection of natural films on the ocean surface , 1996 .

[6]  Ming-Kuang Hsu,et al.  Kuroshio front and oceanic phenomena near Taiwan and in the Southern Okhotsk sea from ERS SAR data , 1997 .

[7]  W. Alpers,et al.  The damping of ocean waves by surface films: A new look at an old problem , 1989 .

[8]  S. Chao,et al.  Response of Kuroshio upwelling to the onset of the northeast monsoon in the sea north of Taiwan: Observations and a numerical simulation , 1992 .

[9]  Manfred Ehrhardt,et al.  Methods of seawater analysis , 1999 .

[10]  P. Santschi,et al.  Estuarine trace metal distributions in Galveston Bay: importance of colloidal forms in the speciation of the dissolved phase , 1999 .

[11]  Pablo Clemente-Colon,et al.  Observations of East Coast upwelling conditions in synthetic aperture radar imagery , 1999, IEEE Trans. Geosci. Remote. Sens..

[12]  Jiayi Pan,et al.  The effects of water temperature on radar scattering from the water surface : An X-band laboratory study , 1997 .

[13]  V. Z̆utić,et al.  Surfactant production by marine phytoplankton , 1981 .

[14]  Antony K. Liu,et al.  Wavelet Analysis of SAR Images for Coastal Monitoring , 2000 .

[15]  P. Tildesley,et al.  Imaging of oceanic features by ERS 1 synthetic aperture radar , 1995 .

[16]  Fuk K. Li,et al.  Air-sea fluxes and surface layer turbulence around a sea surface temperature front , 1991 .