Measurement of water colour using AVIRIS imagery to assess the potential for an operational monitoring capability in the Pamlico Sound Estuary, USA.
The monitoring of water colour parameters can provide an important diagnostic tool for the assessment of aquatic ecosystem condition. Remote sensing has long been used to effectively monitor chlorophyll concentrations in open ocean systems; however, operational monitoring in coastal and estuarine areas has been limited because of the inherent complexities of coastal systems, and the coarse spectral and spatial resolutions of available satellite systems. Data were collected using the National Aeronautics and Space Administration (NASA) Advanced Visible-Infrared Imaging Spectrometer (AVIRIS) flown at an altitude of approximately 20000 m to provide hyperspectral imagery and simulate both MEdium Resolution Imaging Spectrometer (MERIS) and Moderate Resolution Imaging Spectrometer (MODIS) data. AVIRIS data were atmospherically corrected using a radiative transfer modelling approach and analysed using band ratio and linear regression models. Regression analysis was performed with simultaneous field measurements data in the Neuse River Estuary (NRE) and Pamlico Sound on 15 May 2002. Chlorophylla(Chla) concentrations were optimally estimated using AVIRIS bands (9.5 nm) centred at 673.6 and 692.7 nm, resulting in a coefficient of determination (R2) of 0.98. Concentrations of Chromophoric Dissolved Organic Matter (CDOM), Total Suspended Solids (TSS) and Fixed Suspended Solids (FSS) were also estimated, resulting in coefficients of determination ofR2=0.90,0.59 and 0.64, respectively. Ratios of AVIRIS bands centred at or near those corresponding to the MERIS and MODIS sensors indicated that relatively good satellite-based estimates could potentially be derived for water colour constituents at a spatial resolution of 300 and 500 m, respectively.
U.S. Environmental Protection Agency, National Exposure Research Laboratory, Research Triangle Park, NC 27711, USA.
S Lunetta
SL
Ross
U.S. Environmental Protection Agency, National Exposure Research Laboratory, Research Triangle Park, NC 27711, USA.
F Knight
FK
Joseph
University of North Carolina at Chapel Hill, Institute of Marine Sciences, Morehead City, NC 28557, USA.
W Paerl
WP
Hans
University of North Carolina at Chapel Hill, Institute of Marine Sciences, Morehead City, NC 28557, USA.
J Streicher
JS
John
University of North Carolina at Chapel Hill, Institute of Marine Sciences, Morehead City, NC 28557, USA.
L Peierls
LP
Benjamin
University of North Carolina at Chapel Hill, Institute of Marine Sciences, Morehead City, NC 28557, USA.
Gallo
G
Tom
U.S. Environmental Protection Agency, National Exposure Research Laboratory, 944 E. Harmon, Las Vegas, NV 89193, USA.
G Lyon
GL
John
U.S. National Aeronautics and Space Administration, Office of the Associate Director for Operations, Dry den Flight Research Center, Edwards, CA 93523, USA.
H Mace
HM
Thomas
University of North Carolina at Chapel Hill, Institute of Marine Sciences, Morehead City, NC 28557, USA.
P Buzzelli
PB
Christopher