Next Article in Journal
Analysis of Tilt Effect on Notch Depth Profiling Using Thin-Skin Regime of Driver-Pickup Eddy-Current Sensor
Previous Article in Journal
Differential Inductive Sensing System for Truly Contactless Measuring of Liquids′ Electromagnetic Properties in Tubing
Article

New Radiometric Approaches to Compute Underwater Irradiances: Potential Applications for High-Resolution and Citizen Science-Based Water Quality Monitoring Programs

1
EMBIMOS Research Group, Department of Physical and Technological Oceanography, Institute of Marine Sciences, CSIC, 37-49 Passeig Marítim de la Barceloneta, E-08003 Barcelona, Spain
2
Department of Physical and Technological Oceanography, Institute of Marine Sciences, CSIC & Barcelona Expert Center, 37-49 Passeig Marítim de la Barceloneta, E-08003 Barcelona, Spain
3
Marine Technology Unit, CSIC, 37-49 Passeig Marítim de la Barceloneta, E-08003 Barcelona, Spain
*
Author to whom correspondence should be addressed.
Academic Editor: Jose Miguel Lopez-Higuera
Sensors 2021, 21(16), 5537; https://doi.org/10.3390/s21165537
Received: 1 July 2021 / Revised: 10 August 2021 / Accepted: 12 August 2021 / Published: 17 August 2021
(This article belongs to the Section Optical Sensors)
Measuring the diffuse attenuation coefficient (Kd) allows for monitoring the water body’s environmental status. This parameter is of particular interest in water quality monitoring programs because it quantifies the presence of light and the euphotic zone’s depth. Citizen scientists can meaningfully contribute by monitoring water quality, complementing traditional methods by reducing monitoring costs and significantly improving data coverage, empowering and supporting decision-making. However, the quality of the acquisition of in situ underwater irradiance measurements has some limitations, especially in areas where stratification phenomena occur in the first meters of depth. This vertical layering introduces a gradient of properties in the vertical direction, affecting the associated Kd. To detect and characterize these variations of Kd in the water column, it needs a system of optical sensors, ideally placed in a range of a few cm, improving the low vertical accuracy. Despite that, the problem of self-shading on the instrumentation becomes critical. Here, we introduce a new concept that aims to improve the vertical accuracy of the irradiance measurements: the underwater annular irradiance (Ea). This new concept consists of measuring the irradiance in an annular-shaped distribution. We first compute the optimal annular angle that avoids self-shading and maximizes the light captured by the sensors. Second, we use different scenarios of water types, solar zenith angle, and cloud coverage to assess the robustness of the corresponding diffuse attenuation coefficient, Ka. Finally, we derive empirical functions for computing Kd from Ka. This new concept opens the possibility to a new generation of optical sensors in an annular-shaped distribution which is expected to (a) increase the vertical resolution of the irradiance measurements and (b) be easy to deploy and maintain and thus to be more suitable for citizen scientists. View Full-Text
Keywords: annular irradiance; water quality; marine citizen science; diffuse attenuation coefficient; oceanography; light annular irradiance; water quality; marine citizen science; diffuse attenuation coefficient; oceanography; light
Show Figures

Figure 1

MDPI and ACS Style

Rodero, C.; Olmedo, E.; Bardaji, R.; Piera, J. New Radiometric Approaches to Compute Underwater Irradiances: Potential Applications for High-Resolution and Citizen Science-Based Water Quality Monitoring Programs. Sensors 2021, 21, 5537. https://doi.org/10.3390/s21165537

AMA Style

Rodero C, Olmedo E, Bardaji R, Piera J. New Radiometric Approaches to Compute Underwater Irradiances: Potential Applications for High-Resolution and Citizen Science-Based Water Quality Monitoring Programs. Sensors. 2021; 21(16):5537. https://doi.org/10.3390/s21165537

Chicago/Turabian Style

Rodero, Carlos, Estrella Olmedo, Raul Bardaji, and Jaume Piera. 2021. "New Radiometric Approaches to Compute Underwater Irradiances: Potential Applications for High-Resolution and Citizen Science-Based Water Quality Monitoring Programs" Sensors 21, no. 16: 5537. https://doi.org/10.3390/s21165537

Find Other Styles
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Back to TopTop