Picture of neon light reading 'Open'

Discover open research at Strathprints as part of International Open Access Week!

23-29 October 2017 is International Open Access Week. The Strathprints institutional repository is a digital archive of Open Access research outputs, all produced by University of Strathclyde researchers.

Explore recent world leading Open Access research content this Open Access Week from across Strathclyde's many research active faculties: Engineering, Science, Humanities, Arts & Social Sciences and Strathclyde Business School.

Explore all Strathclyde Open Access research outputs...

Semi-empirical correction algorithm for AC-9 measurements in a coccolithophore bloom

McKee, David J.C. and Cunningham, Alex and Craig, Susanne E. (2003) Semi-empirical correction algorithm for AC-9 measurements in a coccolithophore bloom. Applied Optics, 42 (21). pp. 4369-4374. ISSN 1559-128X

Full text not available in this repository. Request a copy from the Strathclyde author

Abstract

Values for the coefficients of absorption (a) and attenuation (c) obtained from AC-9 measurements in coccolithophore blooms do not provide satisfactory inputs for radiance transfer models. We have therefore modified the standard AC-9 scattering correction algorithm by including an extra term, F(λ, λr), which allows for possible wavelength dependence in the scattering phase function. We estimated the magnitude of F(λ, λr), which is unity in the standard algorithm, by adjusting the absorption and scattering values in Hydrolight radiance transfer calculations until the depth profiles of downward irradiance (Ed) and upward radiance (Lu) matched those measured in situ. The modified algorithm was tested with data from a phytoplankton bloom dominated by the coccolithophore Emiliania huxleyi, which occurred in the western English Channel in May 2001. In this paper, we only have sufficient data to adequately constrain the radiance transfer model in one wave band centered on 488 nm. A single value of F(λ, λr) = 1.4 was found to produce satisfactory agreement between modeled and observed profiles at four widely spaced stations within the bloom. Measurements of the ratio of backscattering (bb) to total scattering (b) showed significant wavelength dependence at these stations.