Articles | Volume 365
02 Mar 2015
 | 02 Mar 2015

Multi-scale evaluations of submarine groundwater discharge

M. Taniguchi, M. Ono, and M. Takahashi

Keywords: Submarine groundwater discharge, coastal zone, radon, numerical groundwater model, seepage meter

Abstract. Multi-scale evaluations of submarine groundwater discharge (SGD) have been made in Saijo, Ehime Prefecture, Shikoku Island, Japan, by using seepage meters for point scale, 222Rn tracer for point and coastal scales, and a numerical groundwater model (SEAWAT) for coastal and basin scales. Daily basis temporal changes in SGD are evaluated by continuous seepage meter and 222Rn mooring measurements, and depend on sea level changes. Spatial evaluations of SGD were also made by 222Rn along the coast in July 2010 and November 2011. The area with larger 222Rn concentration during both seasons agreed well with the area with larger SGD calculated by 3D groundwater numerical simulations.