Trends in the Bias of Primary Satellite Ocean-Color Products at a Coastal Site

• Published in: IEEE Geoscience and Remote Sensing Letters
• Main Authors: ZIBORDI Giuseppe, MELIN Frederic, BERTHON Jean-Francois
• Language: English
• Published: IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC 2012
• Subjects: Aerosol Robotic Network
• Online Access: https://publications.jrc.ec.europa.eu/repository/handle/JRC68215; http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=6182578; https://doi.org/10.1109/LGRS.2012.2189753

Trends in the difference between primary satellite ocean-color products and in situ reference data at a coastal site are analyzed and presented. Investigated products are the normalized water-leaving radiance LWN and aerosol optical thickness τa from the Sea-viewing Wide Field-of-view Sensor (SeaWiFS) and the Moderate-Resolution Imaging Spectroradiometer onboard the Aqua and Terra platforms(MODIS-A andMODIS-T, respectively). In situ reference data are from the Ocean-Color component of the Aerosol Robotic Network(AERONET-OC). Restricting the period of investigation to May 2002–April 2010 for SeaWiFS and MODIS-T and July 2002–June 2008 for MODIS-A, results do not indicate any statistically significant trend in the bias of LWN. Biases, determined at around the middle of the considered period, exhibit values from −0.4% to +7.7% for SeaWiFS and from −1.9% to +4.6% forMODIS-T in the 412–555-nm spectral interval. Higher and systematically negative biases from −15.4% to −6.2% are observed for MODIS-A in the same spectral interval. Statistically appreciable trends are observed for τa from SeaWiFS at 443 and 490 nm (approximately +1% per year) and from MODIS-A at 667 nm (+4.7% per year). The biases are very high for both MODIS-A and MODIS-T τa products in the 412–555-nm spectral interval (on average, +21% and +16%, respectively) when compared to SeaWiFS (exhibiting values between +1% and +4%). JRC.H.5 - Land Resources Management