Evaluation of a compact sensor for backscattering and absorption.

Area of Science:

• Oceanography
• Optical Oceanography
• Environmental Science

Background:

• Seawater inherent optical properties (IOPs) are crucial for oceanographic research.
• Absorption coefficient (a) estimates chlorophyll-a, vital for biological oceanography.
• Backscattering coefficient (b(b)) quantifies water turbidity.

Purpose of the Study:

• To test a novel instrument concept for simultaneous measurement of absorption (a) and backscattering (b(b)) coefficients.
• To develop an inversion algorithm using Monte Carlo modeling for data analysis.

Main Methods:

• Simulated light propagation using Monte Carlo modeling.
• Developed an inversion algorithm to derive 'a' and 'b(b)' from simulated instrument signals.
• Tested instrument performance with a wide range of natural seawater IOPs.

Main Results:

• A 6.2 cm instrument with 1 cm radial resolution predicted b(b) within 13.4% relative difference.
• The instrument predicted 'a' within 57% relative difference (90% of values < 29.7% error).
• Constraining the algorithm with additional IOPs can further reduce errors.

Conclusions:

• The novel instrument concept shows promise for accurate in situ IOP measurements.
• Potential applications include autonomous underwater vehicle (AUV) integration and out-of-water sensing.
• This technology could advance oceanographic and environmental monitoring capabilities.