Coastal and Climate Science

09 Mar: Predicting and mapping Hawaiian mesophotic coral ecosystems for sustainable coastal development

PI: Robert Toonen
This study sought to address our fundamental lack of knowledge regarding vulnerable low-light, mesophotic coral ecosystems (at depths of 30-180 m) in order to better manage impacts from invasive species, coastal development, and exploration. By using statistical modeling, combined with machine learning, researchers created predictive maps to illustrate the distribution of mesophotic reefs and invasive algae across the main Hawaiian Islands. They found that all islands had some stretches of coastline identified as highly susceptible to invasion of the green alga Avrainvillea amadelpha, in both shallow and mesophotic depths.

09 Mar: Integration of next-generation sequencing into traditional Hawaiian practices to improve management and restoration of fishponds

PI: Robert Toonen
With Hawaiian fishponds as models of sustainable aquatic resource management, this study uses two important crab species, Portunus sanguinolentus hawaiiensis and Scylla serrata, to explore whether fishponds are self-seeding, importing, or exporting species, and whether traditional harvest practices continue to be viable. Early results show a broad diversity of crab sizes, with a possibility of tagging and tracking crabs outside the fishpond, as well as within.

09 Mar: Assessing the vulnerability of coastal wastewater infrastructure to climate change

PI: Daniele Spirandelli
This research aimed, with community and agency stakeholders, to identify and map critical factors contributing to wastewater infrastructure vulnerability to a changing climate, particularly sea-level rise and extreme precipitation, and to develop a process that builds adaptive capacity into the system. Results showed groundwater inundation as a significant threat to sewer pipes, and a policy gap analysis identified discontinuities in key components of Hawaiʻi’s current onsite management program between land-use planning efforts and state siting regulations.

09 Mar: Longitudinal assessment: Our Project in Hawaiʻi’s Intertidal (OPIHI)

PI: Kanesa Seraphin
This project revisited the Hawaiian intertidal zone, last studied over a decade ago, to document, monitor, and assess changes in species compositions due to factors like climate change, coastal development, and the spread of invasive species. The project trained and mentored undergraduate students as interns, for college credit, gaining important, required hands-on research experience. By engaging these students as well as community members in this place-based research, 48 comprehensive surveys were completed across the state, with preliminary results suggesting the spread of invasive algae and changes to water quality.

09 Mar: Predicting Hawaiʻi water demand under climate change

PI: Michael Roberts
This project studied how climate change may affect future water demand on Oʻahu, focusing on variations in temperature, precipitation, and prevailing climatic conditions. Results imply that microclimates play an important role in demand, with the hot and dry area households using typically 100 gallons more per day than those in cooler, wetter aras. Using water billing data cross-referenced with fine-scale weather data, a model was developed that estimates the growth of Oʻahu aquifer yields needed to satisfy possible shifts in demand (up to 50% increase) under different climate scenarios, or alternatively, the price increases necessary to limit consumption levels.