Variability in measured and modelled remote sensing reflectance for coastal waters at LEO-15

Abstract

A large database of in situ bio-optical measurements were collected at the LEO-15 (Long-term Ecosystem Observatory) off the southern coast of New Jersey, USA. The data were used to quantify the impact of coastal upwelling on near-shore bulk apparent (AOP) and inherent (IOP) optical properties. There was good qualitative agreement between the AOPs and IOPs in space and time. The measured IOPs were used as inputs to the Hydrolight radiative transfer model (RTE). Estimated spectral AOPs from the RTE were strongly correlated (generally R²>0.80) to measured AOPs. If optical closure between in-water measurements was achieved then the RTE was used to construct the spectral remote sensing reflectance. The modelled remote sensing reflectances were compared to satellite-derived reflectance estimates from four different algorithms. Quantitative agreement between the satellite-measured and in-water modelled remote sensing reflectance was good but results were variable between the different models. The strength of the correlation and spectral consistency was variable with space and time. Correlations were strongest in clear offshore waters and lowest in the near-shore turbid waters. In the near-shore waters, the correlation was strongest for blue wavelengths (400–555 nm) but lower for the red wavelengths of light.

Acknowledgments

We wish to thank Taylor Newton, Cristina Orrico, Erica Peters, Dwight Peterson, the Rutgers Marine Field Station staff and R/V Walford crew for assistance in the collection of data. Support was provided by numerous agencies including the Office of Naval Research's COMOP and HyCODE (N00014-97-0767, N0014-99-0196, N00014-99-1-0197), a National Ocean Partnership Award (N00014-97-1-1019) and NASA (NAG5-8674).

Notes

Present address: Virginia Institute of Marine Science, College of William and Mary, P.O. Box 1346, Glouester Pt., VA 23062, USA.

An updated version of a paper originally presented at Oceans from Space ‘Venice 2000’ Symposium, Venice, Italy, 9–13 October 2000.

Additional information

Notes on contributors

Sasha Tozzi

Present address: Virginia Institute of Marine Science, College of William and Mary, P.O. Box 1346, Glouester Pt., VA 23062, USA.