Geospatial model output of coastal wetland changes and inundation impacts under projected sea level rise

The Coastal Bend of Texas includes eleven coastal counties encompassing the Corpus Christi metropolitan area and is characterized by a system of barrier islands, lagoons, and estuaries on a broad coastal plain. The region’s low elevation, land subsidence, small estuarine tidal ranges, and exposure to hurricanes make the area vulnerable to sea level rise. To protect the region’s growing economy, communities need information on the impacts of future sea level rise and the effectiveness of natural and nature-based features (NNBF), which can mitigate coastal risk while offering a variety of additional benefits. This project aims to: Improve and adapt the existing coupled hydrodynamic-marsh model (Hydro-MEM) to the Texas Coastal Bend, Assess sea level rise vulnerabilities and NNBF efficacy using the Hydro-MEM and the Sea Level Affecting Marshes Model (SLAMM), as appropriate, and Form a collaborative Management Transition Advisory Group (MTAG) to produce a knowledge base for modeling and assessing sea level rise resiliency in the region. Within these goals, the project will determine which locations in the Texas Coastal Bend are best suited for NNBF to address sea level rise and improve resilience. This will involve engaging stakeholders to explore how local sea level rise impacts human activities and the efficacy — and practicality — of various NNBF to create more resilient conditions. Local variation across the region means various NNBF scales and approaches are needed, including using multiple lines of defense against sea level rise. The project team will make such determinations by modeling the effects of sea level rise and future hurricane surges, with and without implemented resiliency strategies. To enable this analysis, the team will improve and adapt (e.g., through extension to mangrove habitats) the Hydro-MEM model to the study. The quality of the sea level rise assessments will be enhanced with an innovative and improved use of soil-surface Digital Elevation Models in coastal vegetation, which are documented as essential for assessing microtidal habitats. Further, the project will collaborate with an MTAG that includes representatives from local, regional, and state groups involved in coastal resiliency planning, from both the public and private sectors. What? -- Raster and points-based spatial model products of inundation, organic (plant) productivity, mineral (sediment) deposition, vertical accretion, and landscape changes Where? -- Texas Coastal Bend, including San Antonio Bay, Aransas Bay, Corpus Christi Bay, Baffin Bay, and Laguna Madre Why? -- Predictive spatial-temporal information under various potential cases of relative sea-level rise for improved coastal management and decision-making How? -- High-resolution, mechanistic modeling of coupled hydrodynamics and ecological response When? -- Timelines of various potential cases of relative sea-level rise from year 2020 to 50 years forward (year 2070)