Over the past few years, some methods have been developed to assess submarine groundwater discharge (SGD) on a local scale. However, methodologies for regional scale evaluations (i.e., >100 km) have not occurred. For this reason, a scientist from the University of Hawaii, in collaboration with a scientist from Florida State University, plan to develop a three tiered approach to assess SGD into the sea at regional scales using the following methods: (1) high resolution, temperature calibrated (<0.1'C) geo-corrected aerial infrared surveys; (2) ground-truthing selected sites via natural geochemical tracers (223Ra, 224Ra, 227Th, 228Th); and (3) upscaling the results via typology. The PIs have selected the Kona coast for their study site because of its high apparent SGD, focused nature of the discharge, and lack of surface drainage. Once discharge is established, fluxes of nitrogen species, total phosphorus, inorganic phosphorus, silica, and total chlorophyll will be calculated for the Kona coast and placed within a regional and global context by comparison to stream fluxes.
As regards broader impacts, this study will provide scientists with a new method to assess submarine groundwater discharge on a regional scale, as well as yield new insights into the impact of submarine groundwater discharge on water budgets and biogeochemical cycles in the coastal ocean. The benefits of this study will extend from oceanographers to hydrologist to coastal and water resource managers. Students from both the University of Hawaii and Florida State University will participate in the research study.
