Underwater irradiance is usually measured at low latitude where solar irradiance is strong and weather conditions are ideal. At high latitudes measuring is affected by low sun irradiance, clouds, and cold seawater. Data are often less accurate. These limitations mean that historically few measurements have been carried out.
During High North 17 Campaign 10 meseaurements where carried out in 6 different stations.
What is the solar radiance?
Is the power per unit area received from the Sun in the form of electromagnetic radiation in the wavelength range of the measuring instrument. Irradiance may be measured in space or at the Earth’s surface after atmospheric absorption and scattering. It is measured perpendicular to the incoming sunlight.
How can we use it?
Are used in the environmental monitoring. In particular, the measure performs a bio-optical analysis of natural waters for water quality assessment.
Moreover, our in situ measurements can be used for satellite calibration and for validating the algorithms that derive water quality maps by using satellite data. Satellite missions of interest are: Sentinel-2, Sentinel-3 (from ESA), and the future ASI mission PRISMA.
- ECO-BB2F sensor measures the optical backscattering at both 470 nm and 700 nm wavelengths, and the chlorophyll fluorescence: it provides the chlorophyll concentration in water
- HyperOCR (Hyperspectral Ocean Colour Radiometer ) sensors measure the randiance and irradiance in water and air
At high latitudes measuring
is affected by low sun irradiance,
clouds, and cold seawater..
These limitations mean that historically few measurements have been carried out.,