Center for Coastal Studies

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Systematic Review Shows That Work Done by Storm Waves Can Be Misinterpreted as Tsunami-Related Because Commonly Used Hydrodynamic Equations Are Flawed
Cox, Ronadh; Ardhuin, Fabrice; Dias, Frederic; Autret, Ronan; Beisiegel, Nicole; Earlie, Claire S.; Herterich, James G.; Kennedy, Andrew; Paris, Raphael; Raby, Alison; Schmitt, Pal; Weiss, Robert (2020-02-05)
Coastal boulder deposits (CBD), transported by waves at elevations above sea level and substantial distances inland, are markers for marine incursions. Whether they are tsunami or storm deposits can be difficult to determine, but this is of critical importance because of the role that CBD play in coastal hazard analysis. Equations from seminal work by Nott (1997), here referred to as the Nott Approach, are commonly employed to calculate nominal wave heights from boulder masses as a means to discriminate between emplacement mechanisms. Systematic review shows that this approach is based on assumptions that are not securely founded and that direct relationships cannot be established between boulder measurements and wave heights. A test using an unprecedented dataset of boulders moved by storm waves (with associated sea-state data) shows a lack of agreement between calculations and actual wave heights. The equations return unrealistically large heights, many of which greatly exceed sea states occurring during the boulder-moving storms. This underscores the finding that Nott-Approach wave-height calculations are unreliable. The result is general, because although the field data come from one region (the Aran Islands, Ireland), they represent a wide range of boulder masses and topographic settings and present a valid test of hydrodynamic equations. This analysis demonstrates that Nott Approach equations are incapable of distinguishing storm waves from tsunami transport and that wave heights hindcast from boulder masses are not meaningful. Current hydrodynamic understanding does not permit reliable computation of wave height from boulder measurements. A combination of field, numerical, and experimental approaches is required to quantify relationships between wave power and mass transport onshore. Many CBD interpreted as tsunami deposits based on Nott-Approach analysis may in fact have been emplaced during storms and should therefore be re-evaluated. This is especially important for CBD that have been incorporated into long-term coastal risk assessments, which are compromised if the CBD are misinterpreted. CBD dynamics can be better determined from a combination of detailed field measurements, modeling, and experiments. A clearer understanding of emplacement mechanisms will result in more reliable hazard analysis.
Unifying Advective and Diffusive Descriptions of Bedform Pumping in the Benthic Biolayer of Streams
Grant, Stanley B.; Monofy, Ahmed; Boano, Fulvio; Gomez-Velez, Jesus D.; Guymer, Ian; Harvey, Judson; Ghisalberti, Marco (2020-09-01)
Many water quality and ecosystem functions performed by streams occur in the benthic biolayer, the biologically active upper (similar to 5 cm) layer of the streambed. Solute transport through the benthic biolayer is facilitated by bedform pumping, a physical process in which dynamic and static pressure variations over the surface of stationary bedforms (e.g., ripples and dunes) drive flow across the sediment-water interface. In this paper we derive two predictive modeling frameworks, one advective and the other diffusive, for solute transport through the benthic biolayer by bedform pumping. Both frameworks closely reproduce patterns and rates of bedform pumping previously measured in the laboratory, provided that the diffusion model's dispersion coefficient declines exponentially with depth. They are also functionally equivalent, such that parameter sets inferred from the 2D advective model can be applied to the 1D diffusive model, and vice versa. The functional equivalence and complementary strengths of these two models expand the range of questions that can be answered, for example, by adopting the 2D advective model to study the effects of geomorphic processes (such as bedform adjustments to land use change) on flow-dependent processes and the 1D diffusive model to study problems where multiple transport mechanisms combine (such as bedform pumping and turbulent diffusion). By unifying 2D advective and 1D diffusive descriptions of bedform pumping, our analytical results provide a straightforward and computationally efficient approach for predicting, and better understanding, solute transport in the benthic biolayer of streams and coastal sediments.
Early Holocene Greenland-ice mass loss likely triggered earthquakes and tsunami
Steffen, Rebekka; Steffen, Holger; Weiss, Robert; Lecavalier, Benoit S.; Milne, Glenn A.; Woodroffe, Sarah A.; Bennike, Ole (2020-09-15)
Due to their large mass, ice sheets induce significant stresses in the Earth's crust. Stress release during deglaciation can trigger large-magnitude earthquakes, as indicated by surface faults in northern Europe. Although glacially-induced stresses have been analyzed in northern Europe, they have not yet been analyzed for Greenland. We know that the Greenland Ice Sheet experienced a large melting period in the early Holocene, and so here, we analyze glacially-induced stresses during deglaciation for Greenland for the first time. Instability occurs in southern Greenland, where we use a combined analysis of past sea level indicators and a model of glacially-induced fault reactivation to show that deglaciation of the Greenland Ice Sheet may have caused a large magnitude earthquake or a series of smaller magnitude earthquakes around 10,600 years ago offshore south-western Greenland. The earthquake(s) may have shifted relative sea level observations by several meters. If the earthquake-induced stress release was created during a single event, it could have produced a tsunami in the North Atlantic Ocean with runup heights of up to 7.2 m in the British Isles and up to 7.8 m along Canadian coasts. (C) 2020 The Authors. Published by Elsevier B.V.
Inactivation of Aeromonas hydrophila and Vibrio parahaemolyticus by Curcumin-Mediated Photosensitization and Nanobubble-Ultrasonication Approaches
Rafeeq, Shamil; Shiroodi, Setareh; Schwarz, Michael H.; Nitin, Nitin; Ovissipour, Mahmoudreza (MDPI, 2020-09-16)
The antimicrobial efficacy of novel photodynamic inactivation and nanobubble technologies was evaluated against Vibrio parahaemolyticus and Aeromonas hydrophila as two important aquatic microbial pathogens. Photodynamic inactivation results showed that LED (470 nm) and UV-A (400 nm)-activated curcumin caused a complete reduction in V. parahaemolyticus at 4 and 22 °C, and a greater than 2 log cfu/mL reduction in A. hydrophila, which was curcumin concentration-dependent (p < 0.05). Furthermore, the photodynamic approach caused a greater than 6 log cfu/mL V. parahaemolyticus reduction and more than 4 log cfu/mL of A. hydrophila reduction in aquaponic water samples (p < 0.05). Our results with the nanobubble technology showed that the nanobubbles alone did not significantly reduce bacteria (p > 0.05). However, a greater than 6 log cfu/mL A. hydrophila reduction and a greater than 3 log cfu/mL of V. parahaemolyticus reduction were achieved when nanobubble technology was combined with ultrasound (p < 0.05). The findings described in this study illustrate the potential of applying photodynamic inactivation and nanobubble–ultrasound antimicrobial approaches as alternative novel methods for inactivating fish and shellfish pathogens.
Research Needs, Challenges, and Strategic Approaches for Natural Hazards and Disaster Reconnaissance
Wartman, Joseph; Berman, Jeffrey W.; Bostrom, Ann; Miles, Scott B.; Olsen, Michael; Gurley, Kurtis; Irish, Jennifer L.; Lowes, Laura; Tanner, Troy; Dafni, Jake; Grilliot, Michael; Lyda, Andrew; Peltier, Jaqueline (2020-11-10)
Natural hazards and disaster reconnaissance investigations have provided many lessons for the research and practice communities and have greatly improved our scientific understanding of extreme events. Yet, many challenges remain for these communities, including improving our ability to model hazards, make decisions in the face of uncertainty, enhance community resilience, and mitigate risk. State-of-the-art instrumentation and mobile data collection applications have significantly advanced the ability of field investigation teams to capture quickly perishable data in post-disaster settings. The NHERI RAPID Facility convened a community workshop of experts in the professional, government, and academic sectors to determine reconnaissance data needs and opportunities, and to identify the broader challenges facing the reconnaissance community that hinder data collection and use. Participants highlighted that field teams face many practical and operational challenges before and during reconnaissance investigations, including logistics concerns, safety issues, emotional trauma, and after-returning, issues with data processing and analysis. Field teams have executed many effective missions. Among the factors contributing to successful reconnaissance are having local contacts, effective teamwork, and pre-event training. Continued progress in natural hazard reconnaissance requires adaptation of new, strategic approaches that acquire and integrate data over a range of temporal, spatial, and social scales across disciplines.
A One-Dimensional Model for Turbulent Mixing in the Benthic Biolayer of Stream and Coastal Sediments
Grant, Stanley B.; Gomez-Velez, Jesus D.; Ghisalberti, Marco; Guymer, Ian; Boano, Fulvio; Roche, Kevin; Harvey, Judson (2020-12)
In this paper, we develop and validate a rigorous modeling framework, based on Duhamel's Theorem, for the unsteady one-dimensional vertical transport of a solute across a flat sediment-water interface (SWI) and through the benthic biolayer of a turbulent stream. The modeling framework is novel in capturing the two-way coupling between evolving solute concentrations above and below the SWI and in allowing for a depth-varying diffusivity. Three diffusivity profiles within the sediment (constant, exponentially decaying, and a hybrid model) are evaluated against an extensive set of previously published laboratory measurements of turbulent mass transfer across the SWI. The exponential diffusivity profile best represents experimental observations and its reference diffusivity scales with the permeability Reynolds number, a dimensionless measure of turbulence at the SWI. The depth over which turbulence-enhanced diffusivity decays is of the order of centimeters and comparable to the thickness of the benthic biolayer. Thus, turbulent mixing across the SWI may serve as a universal transport mechanism, supplying the nutrient and energy fluxes needed to sustain microbial growth, and nutrient processing, in the benthic biolayer of stream and coastal sediments.
Predicting Solute Transport Through Green Stormwater Infrastructure With Unsteady Transit Time Distribution Theory
Parker, E. A.; Grant, Stanley B.; Cao, Y.; Rippy, Megan A.; McGuire, Kevin J.; Holden, P. A.; Feraud, M.; Avasarala, S.; Liu, H.; Hung, W. C.; Rugh, M.; Jay, J.; Peng, J.; Shao, S.; Li, D. (2021-02)
In this study, we explore the use of unsteady transit time distribution (TTD) theory to model solute transport in biofilters, a popular form of nature-based or "green" storm water infrastructure (GSI). TTD theory has the potential to address many unresolved challenges associated with predicting pollutant fate and transport through these systems, including unsteadiness in the water balance (time-varying inflows, outflows, and storage), unsteadiness in pollutant loading, time-dependent reactions, and scale-up to GSI networks and urban catchments. From a solution to the unsteady age conservation equation under uniform sampling, we derive an explicit expression for solute breakthrough during and after one or more storm events. The solution is calibrated and validated with breakthrough data from 17 simulated storms at a field-scale biofilter test facility in Southern California, using bromide as a conservative tracer. TTD theory closely reproduces bromide breakthrough concentrations, provided that lateral exchange with the surrounding soil is accounted for. At any given time, according to theory, more than half of the water in storage is from the most recent storm, while the rest is a mixture of penultimate and earlier storms. Thus, key management endpoints, such as the pollutant treatment credit attributable to GSI, are likely to depend on the evolving age distribution of water stored and released by these systems.
Addressing the Contribution of Indirect Potable Reuse to Inland Freshwater Salinization
Bhide, Shantanu V.; Grant, Stanley B.; Parker, Emily A.; Rippy, Megan A.; Godrej, Adil N.; Kaushal, Sujay S.; Prelewicz, Gregory; Saji, Niffy; Curtis, Shannon; Vikesland, Peter J.; Maile-Moskowitz, Ayella; Edwards, Marc A.; Lopez, Kathryn; Birkland, Thomas A.; Schenk, Todd (2021-02-02)
Inland freshwater salinity is rising worldwide, a phenomenon called the freshwater salinization syndrome (FSS). We investigate a potential conflict between managing the FSS and indirect potable reuse, the practice of augmenting water supplies through the addition of reclaimed wastewater to surface waters and groundwaters. From time-series data collected over 25 years, we quantify the contributions of three salinity sources—a wastewater reclamation facility and two rapidly urbanizing watersheds—to the rising concentration of sodium (a major ion associated with the FSS) in a regionally important drinking water reservoir in the Mid-Atlantic United States. Sodium mass loading to the reservoir is primarily from watershed runoff during wet weather and reclaimed wastewater during dry weather. Across all timescales evaluated, sodium concentration in the reclaimed wastewater is higher than in outflow from the two watersheds. Sodium in reclaimed wastewater originates from chemicals added during wastewater treatment, industrial and commercial discharges, human excretion, and down-drain disposal of drinking water and sodium-rich household products. Thus, numerous opportunities exist to reduce the contribution of indirect potable reuse to sodium pollution at this site, and the FSS more generally. These efforts will require deliberative engagement with a diverse community of watershed stakeholders and careful consideration of the local political, social, and environmental context.
Considering COVID-19 through the Lens of Hazard and Disaster Research
Ritchie, Liesel A.; Gill, Duane A. (MDPI, 2021-06-30)
Decades of social science research have taught us much about how individuals, groups, and communities respond to disasters. The findings of this research have helped inform emergency management practices, including disaster preparedness, response, recovery, and mitigation. In the context of the COVID-19 pandemic, most of us—researchers or not—have attempted or are attempting to make sense of what is going on around us. In this article, we assert that we need not examine the pandemic in a vacuum; rather, we can draw upon scholarly and practical sources to inform our thinking about this 21st century catastrophe. The pandemic has provided an “unfortunate opportunity” to revisit what we know about disaster phenomena, including catastrophes, and to reconsider the findings of research from over the years. Drawing upon academic research, media sources, and our own observations, we focus on the U.S. and employ disaster characteristics framework of (1) etiology or origins; (2) physical damage characteristics; (3) disaster phases or cycles; (4) vulnerability; (5) community impacts; and (6) individual impacts to examine perspectives about the ways in which the ongoing pandemic is both similar and dissimilar to conceptualizations about the social dimensions of hazards and disasters. We find that the COVID-19 pandemic is not merely a disaster; rather, it is a catastrophe.
Stratigraphic evidence of two historical tsunamis on the semi-arid coast of north-central Chile
DePaolis, Jessica M.; Dura, Tina; MacInnes, Breanyn; Ely, Lisa L.; Cisternas, Marco; Carvajal, Matias; Tang, Hui; Fritz, Hermann M.; Mizobe, Cyntia; Wesson, Robert L.; Figueroa, Gino; Brennan, Nicole; Horton, Benjamin P.; Pilarczyk, Jessica E.; Corbett, D. Reide; Gill, Benjamin C.; Weiss, Robert (Pergamon-Elsevier, 2021-07-21)
On September 16, 2015, a Mw 8.3 earthquake struck the north-central Chile coast, triggering a tsunami observed along 500 km of coastline, between Huasco (28.5°S) and San Antonio (33.5°S). This tsunami provided a unique opportunity to examine the nature of tsunami deposits in a semi-arid, siliciclastic environment where stratigraphic and sedimentological records of past tsunamis are difficult to distinguish. To improve our ability to identify such evidence, we targeted one of the few low-energy, organic-rich depositional environments in north-central Chile: Pachingo marsh in Tongoy Bay (30.3°S). We found sedimentary evidence of the 2015 and one previous tsunami as tabular sand sheets. Both deposits are composed of poorly to moderately sorted, gray-brown, fine-to medium-grained sand and are distinct from underlying and overlying organic-rich silt. Both sand beds thin (from ∼20 cm to <1 cm) and fine landward, and show normal grading. The older sand bed is thicker and extends over 125 m further inland than the 2015 tsunami deposit. To model the relative size of the tsunamis that deposited each sand bed, we employed tsunami flow inversion. Our results show that the older sand bed was produced by higher flow speeds and depths than those in 2015. Anthropogenic evidence along with 137Cs and 210Pb dating constrains the age of the older tsunami to the last ∼110 years. We suggest that the older sand bed was deposited by the large tsunami in 1922 CE sourced to the north of our study site. This deposit represents the first geologic evidence of a pre-2015 tsunami along the semi-arid north-central Chile coast and highlights the current and continuing tsunami hazard in the region.
Anticipating and adapting to the future impacts of climate change on the health, security and welfare of low elevation coastal zone (LECZ) communities in Southeastern USA
Allen, Thomas; Behr, Joshua; Bukvic, Anamaria; Calder, Ryan S. D.; Caruson, Kiki; Connor, Charles; D'Elia, Christopher; Dismukes, David; Ersing, Robin; Franklin, Rima; Goldstein, Jesse; Goodall, Jonathon; Hemmerling, Scott; Irish, Jennifer L.; Lazarus, Steven; Loftis, Derek; Luther, Mark; McCallister, Leigh; McGlathery, Karen; Mitchell, Molly; Moore, William B.; Nichols, C. Reid; Nunez, Karinna; Reidenbach, Matthew; Shortridge, Julie; Weisberg, Robert; Weiss, Robert; Donelson Wright, Lynn; Xia, Meng; Xu, Kehui; Young, Donald; Zarillo, Gary; Zinnert, Julie C. (MDPI, 2021-10-29)
Low elevation coastal zones (LECZ) are extensive throughout the southeastern United States. LECZ communities are threatened by inundation from sea level rise, storm surge, wetland degradation, land subsidence, and hydrological flooding. Communication among scientists, stakeholders, policy makers and minority and poor residents must improve. We must predict processes spanning the ecological, physical, social, and health sciences. Communities need to address linkages of (1) human and socioeconomic vulnerabilities; (2) public health and safety; (3) economic concerns; (4) land loss; (5) wetland threats; and (6) coastal inundation. Essential capabilities must include a network to assemble and distribute data and model code to assess risk and its causes, support adaptive management, and improve the resiliency of communities. Better communication of information and understanding among residents and officials is essential. Here we review recent background literature on these matters and offer recommendations for integrating natural and social sciences. We advocate for a cyber-network of scientists, modelers, engineers, educators, and stakeholders from academia, federal state and local agencies, non-governmental organizations, residents, and the private sector. Our vision is to enhance future resilience of LECZ communities by offering approaches to mitigate hazards to human health, safety and welfare and reduce impacts to coastal residents and industries.
Rapid prediction of peak storm surge from tropical cyclone track time series using machine learning
Lee, Jun-Whan; Irish, Jennifer L.; Bensi, Michelle T.; Marcy, Douglas C. (Elsevier, 2021-12-01)
Rapid and accurate prediction of peak storm surges across an extensive coastal region is necessary to inform assessments used to design the systems that protect coastal communities’ life and property. Significant advances in high-fidelity, physics-based numerical models have been made in recent years, but use of these models for probabilistic forecasting and probabilistic hazard assessment is computationally intensive. Several surrogate modeling approaches based on existing databases of high-fidelity synthetic storm surge simulations have been recently suggested to reduce computational burden without substantial loss of accuracy. In these previous studies, however, the surrogate modeling approaches relied on a tropical cyclone condition at one moment (usually at or near landfall), which is not always most correlated with the peak storm surge. In this study, a new one-dimensional convolutional neural network model combined with principal component analysis and a k-means clustering (C1PKNet) is presented that can rapidly predict peak storm surge across an extensive coastal region from time-series of tropical cyclone conditions, namely the storm track. The C1PKNet model was trained and cross-validated for the Chesapeake Bay area of the United States using existing database of 1031 high-fidelity storm surge simulations, including both landfalling and bypassing storms. Moreover, the performance of the C1PKNet model was evaluated based on observations from three historical hurricanes (Hurricane Isabel in 2003, Hurricane Irene in 2011, and Hurricane Sandy in 2012). The results indicate that the C1PKNet model is computationally efficient and can predict peak storm surges from realistic tropical cyclone track time-series. We believe that this new surrogate model can enhance coastal resilience by providing rapid storm surge predictions.
Changing impacts of Alaska-Aleutian subduction zone tsunamis in California under future sea-level rise
Dura, Tina; Garner, Andra J.; Weiss, Robert; Kopp, Robert E.; Engelhart, Simon E.; Witter, Robert C.; Briggs, Richard W.; Mueller, Charles S.; Nelson, Alan R.; Horton, Benjamin P. (Springer Nature, 2021-12-08)
The amplification of coastal hazards such as distant-source tsunamis under future relative sea-level rise (RSLR) is poorly constrained. In southern California, the Alaska-Aleutian subduction zone has been identified as an earthquake source region of particular concern for a worst-case scenario distant-source tsunami. Here, we explore how RSLR over the next century will influence future maximum nearshore tsunami heights (MNTH) at the Ports of Los Angeles and Long Beach. Earthquake and tsunami modeling combined with local probabilistic RSLR projections show the increased potential for more frequent, relatively low magnitude earthquakes to produce distant-source tsunamis that exceed historically observed MNTH. By 2100, under RSLR projections for a high-emissions representative concentration pathway (RCP8.5), the earthquake magnitude required to produce >1 m MNTH falls from ~Mw9.1 (required today) to Mw8.0, a magnitude that is ~6.7 times more frequent along the Alaska-Aleutian subduction zone.
Perceived services and disservices of natural treatment systems for urban stormwater: Insight from the next generation of designers
Rippy, Megan A.; Pierce, Gregory; Feldman, David; Winfrey, Brandon; Mehring, Andrew S.; Holden, Patricia A.; Ambrose, Richard; Levin, Lisa A. (Wiley, 2022)
1. Natural treatment systems (NTS) for stormwater have the potential to provide a myriad of ecosystem services to society. Realizing this potential requires active collaboration among engineers, ecologists and landscape planners and begins with a paradigm shift in communication whereby these groups are made aware of each other's perceptions about NTS and the presence of knowledge gaps that their respective disciplines can bridge. 2. Here we participate in the first part of what we hope will be a reciprocal exchange: presenting results from a landscape perceptions survey to urban planners, ecologists and landscape architects that illustrates how the next generation of engineers perceives NTS relative to other landscape features, and the implications of those perceptions for future infrastructure development. 3. Our results suggest that although lawns, gardens and native ecosystems were perceived as multifunctional, providing characteristic bundles of services/disservices, perceptions of NTS were more variable (i.e. there was no social norm for their perception). 4. Environmental worldviews, knowledge, attitudes about ecosystem services and demographics were all significant drivers of perceived services. However, students had difficulty identifying NTS correctly, and factual knowledge about NTS did not help students associate NTS with typical design services like flood reduction more than features not designed for those purposes, such as lawns. This suggests that engineering students lack familiarity with the outward appearance of NTS and have difficulty placing NTS services into a broader landscape context. 5. Expertise from urban planning and ecology could help bridge these knowledge gaps, improving the capacity of tomorrow's engineers to co-design NTS to meet diverse community needs.
Prevalence of Microplastics in the Eastern Oyster Crassostrea virginica in the Chesapeake Bay: The Impact of Different Digestion Methods on Microplastic Properties
Aung, Thet; Batish, Inayat; Ovissipour, Reza (MDPI, 2022-01-10)
This study aimed to determine the microplastic prevalence in eastern oysters (C. virginica) in three sites in the Chesapeake Bay in Virginia and optimize the digestion methods. The digestion results illustrate that the lowest recovery rate and digestion recovery were related to enzymatic, enzymatic + hydrogen peroxide (H₂O₂), and HCl 5% treatments, while the highest digestion recovery and recovery rate were observed in H₂O₂ and basic (KOH) treatments. Nitric acid digestion resulted in satisfying digestion recovery (100%), while no blue polyethylene microplastics were observed due to the poor recovery rate. In addition, nitric acid altered the color, changed the Raman spectrum intensity, and melted polypropylene (PP) and polyethylene terephthalate (PET). In order to determine the number of microplastics, 144 oysters with an approximately similar size and weight from three sites, including the James River, York River, and Eastern Shore, were evaluated. Fragments were the most abundant microplastics among the different microplastics, followed by fibers and beads, in the three sites. A significantly higher number of fragments were found in the James River, probably due to the greater amount of human activities. The number of microplastics per gram of oyster tissue was higher in the James River, with 7 MPs/g tissue, than in the York River and Eastern Shore, with 6.7 and 5.6 MPs/g tissue.
Can Smart Stormwater Systems Outsmart the Weather? Stormwater Capture with Real-Time Control in Southern California
Parker, Emily A.; Grant, Stanley B.; Sahin, Abdullah; Vrugt, Jasper A.; Brand, Matthew W. (2022-01-14)
Stormwater capture systems have the potential to address many urban stormwater management challenges, particularly in water-scarce regions like Southern California. Here, we investigate the potential best-case limits of water supply and stormwater retention benefits delivered by a 10,000 m3 stormwater capture system equipped with real-time control (RTC) on a university campus in Southern California. Using a copula-based conditional probability analysis, two performance metrics (percent of water demand satisfied and the percent of stormwater runoff captured) are benchmarked relative to (1) precipitation seasonality (historical rainfall and a counterfactual in which the same average annual rainfall is distributed evenly over the year); (2) annual precipitation (dry, median, and wet years); and (3) three RTC algorithms (no knowledge of future rainfall or perfect knowledge of future rainfall 1 or 2 days in advance). RTC improves stormwater retention, particularly for the highly seasonal rainfall patterns in Southern California, but not water supply. Improvements to the latter will likely require implementing stormwater capture RTC in conjunction with other stormwater infrastructure innovations, such as spreading basins for groundwater recharge and widespread adoption of green stormwater infrastructure.
Boulder dislodgement during coastal storms and tsunamis: Insights from a new ensemble model
Weiss, Robert; Irish, Jennifer L.; Goodman Tchernov, Beverly (American Geophysical Union, 2022-03-01)
Boulders are excellent candidate deposits to study coastal inundation events by storms and tsunamis due to their significant preservation potential. However, it is difficult to infer how and what forcing dislodged the boulder. We present a new model that enables ensemble and Monte-Carlo-type simulations to study the sensitivity of boulder, the fluid flow, and environmental parameters. Our examples show that boulder transport is complex and nonlinear, and to acknowledge the uncertainties of the boulder's preexisting transport conditions, a range of velocities and environmental parameters should be used to quantify the flow that caused boulder dislodgement.
Five state factors control progressive stages of freshwater salinization syndrome
Kaushal, Sujay S.; Mayer, Paul M.; Likens, Gene E.; Reimer, Jenna E.; Maas, Carly M.; Rippy, Megan A.; Grant, Stanley B.; Hart, Ian; Utz, Ryan M.; Shatkay, Ruth R.; Wessel, Barret M.; Maietta, Christine E.; Pace, Michael L.; Duan, Shuiwang; Boger, Walter L.; Yaculak, Alexis M.; Galella, Joseph G.; Wood, Kelsey L.; Morel, Carol J.; Nguyen, William; Querubin, Shane Elizabeth C.; Sukert, Rebecca A.; Lowien, Anna; Houde, Alyssa Wellman; Roussel, Anais; Houston, Andrew J.; Cacopardo, Ari; Ho, Cristy; Talbot-Wendlandt, Haley; Widmer, Jacob M.; Slagle, Jairus; Bader, James A.; Chong, Jeng Hann; Wollney, Jenna; Kim, Jordan; Shepherd, Lauren; Wilfong, Matthew T.; Houlihan, Megan; Sedghi, Nathan; Butcher, Rebecca; Chaudhary, Sona; Becker, William D. (Wiley, 2022-03-16)
Factors driving freshwater salinization syndrome (FSS) influence the severity of impacts and chances for recovery. We hypothesize that spread of FSS across ecosystems is a function of interactions among five state factors: human activities, geology, flowpaths, climate, and time. (1) Human activities drive pulsed or chronic inputs of salt ions and mobilization of chemical contaminants. (2) Geology drives rates of erosion, weathering, ion exchange, and acidification-alkalinization. (3) Flowpaths drive salinization and contaminant mobilization along hydrologic cycles. (4) Climate drives rising water temperatures, salt stress, and evaporative concentration of ions and saltwater intrusion. (5) Time influences consequences, thresholds, and potentials for ecosystem recovery. We hypothesize that state factors advance FSS in distinct stages, which eventually contribute to failures in systems-level functions (supporting drinking water, crops, biodiversity, infrastructure, etc.). We present future research directions for protecting freshwaters at risk based on five state factors and stages from diagnosis to prognosis to cure.
Modeling Coastal Environmental Change and the Tsunami Hazard
Weiss, Robert; Dura, Tina; Irish, Jennifer L. (Frontiers, 2022-05-02)
The hazard from earthquake-generated tsunami waves is not only determined by the earthquake's magnitude and mechanisms, and distance to the earthquake area, but also by the geomorphology of the nearshore and onshore areas, which can change over time. In coastal hazard assessments, a changing coastal environment is commonly taken into account by increasing the sea-level to projected values (static). However, sea-level changes and other climate-change impacts influence the entire coastal system causing morphological changes near- and onshore (dynamic). We compare the run-up of the same suite of earthquake-generated tsunamis to a barrier island-marsh-lagoon-marsh system for statically adjusted and dynamically adjusted sea level and bathymetry. Sea-level projections from 2000 to 2100 are considered. The dynamical adjustment is based on a morphokinetic model that incorporates sea-level along with other climate-change impacts. We employ Representative Concentration Pathways 2.6 and 8.5 without and with treatment of Antarctic Ice-sheet processes (known as K14 and K17) as different sea-level projections. It is important to note that we do not account for the occurrence probability of the earthquakes. Our results indicate that the tsunami run-up hazard for the dynamic case is approximately three times larger than for the static case. Furthermore, we show that nonlinear and complex responses of the barrier island-marsh-lagoon-marsh system to climate change profoundly impacts the tsunami hazard, and we caution that the tsunami run-up is sensitive to climate-change impacts that are less well-studied than sea-level rise.
Moving from interdisciplinary to convergent research across geoscience and social sciences: challenges and strategies
Finn, Donovan; Mandli, Kyle; Bukvic, Anamaria; Davis, Christopher A.; Haacker, Rebecca; Morss, Rebecca E.; O'Lenick, Cassandra R.; Wilhelmi, Olga; Wong-Parodi, Gabrielle; Merdjanoff, Alexis A.; Mayo, Talea L. (IOP Publishing, 2022-06)

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