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  • Temporal variability in the relationship between line height absorption and chlorophyll concentration: a case study from the Northern Gulf of Alaska
Title: Temporal variability in the relationship between line height absorption and chlorophyll concentration: a case study from the Northern Gulf of Alaska
The Line Height Absorption (LHA) method uses absorption of light to estimate chlorophyll-a. While most users consider regional variability and apply corrections, the effect of temporal variability is typically not explored. The Northern Gulf of Alaska (NGA) was selected for this study because there was no published regional value and its large swings in temporal productivity would make it a good candidate to evaluate the effect of temporal variability on the relationship. The mean NGA value of 0.0114 obtained here should be treated with caution, as variation in the slope of the relationship (aLH*), and thus chlorophyll-a estimates, in the NGA region varied by ∼25% between spring (aLH* = 0.0109) and summer (aLH* = 0.0137). Results suggest that this change is driven by a shift in pigment packaging and cell size associated with changes in mixed layer depth and stratification. Consideration of how temporal variability may affect the accuracy of the LHA method in other regions is thus recommended.  more » « less
Award ID(s):
2322806 1656070
PAR ID:
10519468
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
Optica Publishing Group
Date Published:
Journal Name:
Optics Express
Edition / Version:
1
Volume:
32
Issue:
12
ISSN:
1094-4087
Page Range / eLocation ID:
20491
Subject(s) / Keyword(s):
Chlorophyll, absorption, production
Format(s):
Medium: X Other: pdf
Sponsoring Org:
National Science Foundation
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