Toward Closure of Upwelling Radiance in Coastal Waters
Abstract
We present three methods for deriving water-leaving radiance Lw ( λ) and remote-sensing reflectance using a hyperspectral tethered spectral radiometer buoy (HyperTSRB), profiled spectroradiometers, and Hydrolight simulations. Average agreement for 53 comparisons between HyperTSRB and spectroradiometric determinations of Lw ( λ) was 26%, 13%, and 17% at blue, green, and red wavelengths, respectively. Comparisons of HyperTSRB (and spectroradiometric) Lw ( λ) with Hydrolight simulations yielded percent differences of 17% (18%), 17% (18%), and 13% (20%) for blue, green, and red wavelengths, respectively. The differences can be accounted for by uncertainties in model assumptions and model input data (chlorophyll fluorescence quantum efficiency and the spectral chlorophyll-specific absorption coefficient for the red wavelengths, and scattering corrections for input ac-9 absorption data and volume scattering function measurements for blue wavelengths) as well as radiance measurement inaccuracies [largely differences in the depth of the Lu ( λ, z ) sensor on the HyperTSRB .]
- Publication:
-
Applied Optics
- Pub Date:
- March 2003
- DOI:
- 10.1364/AO.42.001574
- Bibcode:
- 2003ApOpt..42.1574C
- Keywords:
-
- radiometry;
- seawater;
- reflectivity;
- remote sensing;
- colour;
- visible spectra