Webinar

Hurricane Ecosystem Response Synthesis Network

Each month, the HERS team would like to facilitate connection within our Network, progress on upcoming research on the ecology of tropical cyclones, and help share the latest findings in HERS related research.

Please check out our tabs below for what we will be hosting each month. In addition to hosting invited speakers, we will also use these virtual meetings to help form working groups interested in investigations related to our three research focal themes: (i) interactions among ecosystem pre-storm conditions and storm characteristics on ecosystem responses, (ii) roles of eco-evolutionary history, life history, and biodiversity on ecosystem responses, and (iii) feedbacks among natural and social-economic systems that confer resistance and resilience to tropical cyclones. 

 

January 2022: The engineering performance of mangrove ecosystems to mitigate the effects of hurricanes on our built environment

 

tori_tomiczek_JanHERSweb

 

Dr. Tori Tomiczek
Assistant Professor
United States Naval Academy 

January 18th @ 1:00 pm US eastern : Free Registration and Webinar information HERE

 

Rising seas, tropical cyclones, and tsunamis threaten increasingly populated coastal areas, leaving coastal communities searching for sustainable, resilient adaptation solutions to mitigate the impacts of chronic and acute coastal flood hazards. While various hazard mitigation alternatives spanning the green-gray engineering spectrum have been considered, an emerging body of literature has identified natural and nature-based features (NNBF) as effective in attenuating waves and water levels over land and providing co-benefits including carbon storage, habitat, and recreation. However, uncertainty about the engineering performance of these systems limits their widespread application in coastal planning and design.

This work investigates parcel-scale effects of the Rhizophora mangle subject to waves. Post-storm damage observations after Hurricane Irma in the Florida Keys identified that near-coast residential structures shielded by mangroves of 10-50 m cross-shore width consistently experienced less damage than neighboring structures with other shoreline archetypes. Based on these observations, a prototype-scale physical model of the Rhizophora trunk-prop root system was created to measure mangrove effects on hydrodynamic transformation and wave load reduction on sheltered inland structures. A method for quantifying the projected area of a mangrove forest for predicting wave attenuation was also developed. Results indicate that Rhizophora forests of moderate cross shore width have a measurable effect on wave attenuation, with wave height decay dependent on water depth and forest density. However, a balance between the desired engineering performance, ecological requirements, and social considerations are required to successfully implement these natural systems to mitigate coastal flood hazards. Ongoing work through NSF will investigate the reliability of these systems by synthesizing field and laboratory experiments and working with experts from academia, industry, and government to inform experimental design and dissemination.

 

October 2021: Coastal habitat and community responses to tropical cyclones in a temperate, sub-tropical estuary

Dr. Yin San Stacy Zhang

 

Dr. Yin San Stacy Zhang
Postdoctoral Researcher
Institute of Marine Sciences, University of North Carolina Chapel Hill

Please email HERSresearch@vims.edu if you would like a link to the recording


Major storms can alter coastal ecosystem structure and functioning in a multitude of direct and indirect ways including habitat destruction, stormwater-related water-quality degradation, and mortality of marine organisms, among others. From 2010-2020, multiple hurricanes of varying intensities impacted the southern Outer Banks of North Carolina. Using a combination of monthly trawls and contemporaneous seagrass and oyster reef surveys, we examined habitat continuity and changes in seagrass-associated fish communities to evaluate whether these disturbances changed the nursery role of shallow-water biogenic habitats. Our analysis revealed that fish catch may be depressed for roughly two weeks after storm passage but over longer time frames, appeared largely similar to corresponding no-storm years. The overall resilience exhibited by fishes was likely underpinned by the relative stability of the seagrass habitat itself, which appeared principally undamaged by storms. However, storm intensity plays a large role in overall storm effect, as the greatest magnitude cyclone in our observation period, Hurricane Florence, not only damaged oyster reefs that had previously been unaffected by earlier cyclones but also caused the greatest decline in fish catches. These findings suggest that fish communities and coastal habitats may be insensitive to mild tropical cyclones, but a pressing question appears to be whether they will remain resilient to storm impacts if the frequency and intensity of these disturbances increase as one syndrome of global climate change. 

November 2021: Quantifying disturbance and recovery in estuaries: tropical cyclones and high frequency measures of oxygen and salinity

Dr. Cal Buelo


Dr. Cal Buelo
Postdoctoral Researcher
University of Wisconsin Center for Limnology

Recording available HERE until January 5th, 2022

 

Tropical cyclones are important drivers of disturbance in estuaries. Several mechanisms can lead to storm impacts and estuaries are dynamic and diverse systems, making identifying disturbance and recovery difficult and often limiting studies to one or a few sites or tropical cyclones. We applied a new method for detecting disturbance and recovery to long-term and high-frequency measurements of salinity and dissolved oxygen from NOAA’s National Estuarine Research Reserve System, analyzing the impacts of 59 tropical cyclones at 19 estuaries across the eastern United States. We were able quantify disturbance occurrence, timing, recovery time, and severity and ask what storm and location properties are associated with changes in these disturbance characteristics. Salinity disturbances generally started earlier than dissolved oxygen disturbances and lasted longer. Most recoveries occurred within days, though some disturbances lasted weeks or months. Recovery time was positively correlated with disturbance severity for both variables. Both storm (especially precipitation) and location properties were related to disturbance characteristics. Our findings demonstrate the power of high-frequency, long-term, and cross-system data, when combined with appropriate statistical methods, to provide insights that improve understanding and potentially management of estuarine resilience to disturbances.

December 2021: The “new normal” high rainfall tropical cyclones: Linkage to harmful cyanobacterial bloom expansion into estuarine and coastal waters

Dr. Hans W. Paerl


Dr. Hans W. Paerl
Professor of Marine & Environmental Sciences & Engineering
Institute of Marine Sciences, University of North Carolina

Recording available HERE until January 15th, 2022

 

Global warming is generating more intense, elevated rainfall from tropical and extra-tropical storms, which have led to record flooding along the storm tracks, extending from the coast to inland watersheds. In addition to delivering elevated nutrient (N and P) and other contaminant loads to receiving riverine, estuarine, and coastal waters, floodwater also tend to reduce salinity in these waters.  The combined effect of elevated nutrient loads and “freshening” of downstream waters is promoting eutrophication (“new production” from a carbon perspective) and expanding the window of opportunity for harmful cyanobacterial blooms, or CyanoHABs, to proliferate. Elevated stormwater runoff events followed by periods of protracted droughts are the perfect “storm scenario” for downstream proliferation of CyanoHABs, which will benefit from elevated nutrient supplies, depressed salinity levels and increases in water residence times.  This, combined with warming is a potent combination of changing environmental conditions favoring expansion of CyanoHABs along the entire freshwater to marine continuum. Examples of this scenario are now evident in numerous estuarine and coastal ecosystems, including the Mississippi-Atchafalaya drainage into the northern Gulf of Mexico, Florida’s coastal lagoons and estuaries draining Lake Okeechobee, the Albemarle-Pamlico estuarine complex in North Carolina, the San Francisco Bay Delta, as well as the Yangtze River Delta in China. This scenario presents multiple CyanoHAB mitigation challenges, in that both watershed nutrient loading will need to be reduced to new threshold levels and water retention strategies need to be optimized to retain and process nutrients in the watershed upstream from CyanoHAB sensitive receiving waters.