sea-level rise response modeling to inform planning

Karen Thorne & Kevin Buffington USGS Western Ecological Research Center RAE Conference December 12th, 10:30-12 “A Web-Based Interactive Decision-Support Tool for Adaptation of Coastal Urban and Natural Ecosystems (ACUNE) in Southwest Florida”

Project and Science Lead: Peter Sheng, University of Florida ([email protected]) Coordination Lead: Michael Savarese, Florida University ([email protected])

Team: Christine Angelini, Mike Barry, Kevin Buffington, Justin Davis, Felix Jose, Ken Krause, David Letson, Vladimir Paramygin, Karen Thorne, Chuen “Andy” Hsu, Adail Rivera-Nieves, Sean Sharp, Kun Yang We are developing ACUNE to enable Adaption of Coastal Urban and Natural Systems for A Sustainable & Economically Healthy SW Florida in the Context of Increasing Future Inundation Risk

Study Domain

Largest Mangrove Forest in Gulf of Mexico region Ecosystem Services: Ecosystem Diversity, Fishery Habitat, Flood Protection Coastal Vulnerability to Sea-level rise

• Projected sea-level rise pose a risk to coastal , including tidal and • Mangroves provide wildlife habitat and valuable ecosystem services, including protecting infrastructure from flooding and storms • Mangroves provide a lot of carbon storage • Coastal wetlands require mineral and organic sediment inputs to build elevations to keep pace with sea-level rise.

Red, white, and black mangroves in FL Mangrove ecosystems

From: Lee et al. Global Ecology and Biogeography, 2014, 23: 726–743 Important Habitat

They provide habitat for many land and sea species, protect shorelines from erosion, and act as a natural carbon sink.

From WWF, Matt Twombly SW Florida Hurricane History

36 Hurricanes (1861-2017) Hurricane Irma Track (2017) Recurrence interval = 4.3 yrs

Orlando Sentinel

https://coast.noaa.gov/hurricanes/ Hurricane History

https://www.miamiherald.com/news/local/environment/article209148999.html Research Questions:

How will the mangrove/ ecosystem respond to sea-level rise?

When and where will wetland transgression occur?

What is the value of mangroves in flood protection from sea-level rise and storms? Objectives • Predict the future distribution of tidally influenced mangrove forest and for Collier County, FL • Integrate hydrodynamic (CH3D-SWAN) and ecosystem response mangrove/marsh models to project future distribution of ecosystems under sea-level rise scenarios and hurricanes • Use existing data to calibrate model

Case study: Mangrove Expansion Ten Thousand NWR

Mangrove Area 1927: 5,403 ha 2005: 7,281 ha

35% Increase Up-slope migration

In situ elevation adjustment

Krauss et al. 2011. J. Coast. Conserv. 15, 629–638. Mangrove model development to inform management: Mangrove Evolution Response to Climate Change [MERCC]

• Scale relevant to resource managers and urban stakeholders • Framework: • Stem density model with multiple age classes (seed, seedling, adult) for wetland vegetation • Main environmental drivers: inundation and salinity (SLR and Hurricanes) • Competition within & between species • Explicitly linked to a soil development model • Scenarios: • Sea-level rise • Hurricanes [future] Soil cohort model – vertical elevation growth

• Predicts elevations with sea- level rise. • Considers dominant below & above ground processes • Calibrated with local accretion data (cores, SETs) • Requires digital elevation model & water level data

From WWF, Matt Twombly Model Calibration Data

• Surface elevation tables (SETs) • Non-linear relationship between accretion rates and elevation • Soil Cores • High organic matter content • Low mineral input • High porosity

Krauss et al. 2017 Model Assumptions –species Open Water Red mangrove have different environmental Black mangrove White mangrove Buttonwood tolerances Salt marsh Freshwater marsh Upland Forest Model Assumptions –species have different tolerances and occur at certain distances from and at particular elevations

2D environmental parameter space: Mean (+1 SD) elevation & distance from shore Vegetation Distribution NOAA C-CAP (2010)

Goal: New distributions of vegetation for 2030, 2070, and 2100

(NOAA Office of ) 100 year scenarios Linear SLR Preliminary Results

2 mm/yr

Open Water Red mangrove 4 mm/yr Black mangrove White mangrove Buttonwood Salt marsh Freshwater marsh Upland Forest

8 mm/yr Conclusion

• Mangrove/marsh ecosystems are complex & dynamic, requiring new modeling tools to assess their response to environmental change

• We will use this to inform a regional vulnerability analysis for sea-level rise and hurricanes.

• Modeling can be used to answer management agency specific questions about sea-level rise, hurricane, and other climate change impacts, as well as inform restoration questions Thank you

Karen Thorne, PhD USGS WERC [email protected] 916 -502- 2996

Funders: U.S. Geological Survey & A Cooperative Agreement (#2624084) with NOAA NCCOS