Ep125 - Sonar mapping of groundwater discharge in coastal areas

In this episode, we talk with Mary Rose P. Gabuyo about her study on using low-cost fish finders — the kind used for recreational sport fishing — to detect and map submarine groundwater discharge (SGD) in coastal waters. SGD refers to all direct discharge of subsurface fluids across the seafloor, including fresh groundwater, recirculated seawater, and gases like CO₂ and methane. Despite its ecological significance, mapping SGD remains a challenge because conventional methods are costly, tedious, and require specialized equipment. This study tested whether recreational-grade echosounders could do the job — and they did.📚Reference: Gabuyo MRP, Siringan FP. 2022. Utility of low-cost recreational-grade echosounders in imaging and characterizing bubbly coastal submarine groundwater discharge. Journal of Hydrology X. 14:100118.