A Secchi disc being lowered into clear water

Image
A Secchi disc being lowered into clear water
Licence
Download original image Attribution Dr Renee Gruber (Australian Institute of Marine Science), Australian Institute of Marine Science

Description

A Secchi disc with alternating black and white quarters is lowered into clear water in the Great Barrier Reef Marine Park during sampling for the GBR Marine Monitoring Program, February 2019. Secchi discs are a simple and reliable way to measure the depth to which light penetrates the water.