The Eastern oyster ( is an important commercial bivalve species which also has numerous ecological roles including biogeochemical cycling, providing habitat for larval fish and crustaceans, and reducing the impacts of coastal storms. Oil may pose a threat to oyster larvae swimming in the water column, leading to potential negative effects on survival, growth, and development. Oil toxicity may be further enhanced by chemical changes in the presence of sunlight. This study determined the toxicity of thin oil sheens with and without ultraviolet (UV) light, then examined the latent effects of the short term exposure on longer term survival and swimming ability. Larval were exposed to four different oil sheen thicknesses for 24 h with either no UV light or 2-h UV light. Following the exposure, larvae were transferred to clean seawater and no UV light for 96 h. The presence of a 2-h UV light exposure significantly increased oyster mortality, indicating photo-enhanced toxicity. The LC for a 24-h oil sheen exposure without UV was 7.26 µm (23 µg/L PAH) while a 2 h-UV exposure lowered the sheen toxicity threshold to 2.67 µm (10 µg/L PAH). A previous 24-h oil sheen exposure (≥0.5 µm) led to latent effects on larval oyster survival, regardless of previous UV exposure. Sublethal impacts to larval oyster swimming behavior were also observed from the previous oil sheen exposure combined with UV exposure. This study provides new data for the toxicity of thin oil sheens to a sensitive early life stage of estuarine bivalve.

Coastal defense structures (e.g., dikes, seawalls) protect vulnerable communities along marine coastlines and estuaries from the physical and chemical influences of adjacent water bodies. These structures are susceptible to overtopping or breaching by tides and waves, with risks amplified by climate change-induced sea-level rise. Repeated inundation by saline water can contaminate freshwater resources and salinize soil, impacting land-use activities, including agricultural productivity. Managed ecosystem-based dike realignment and salt marsh restoration can provide alternatives to traditional coastal adaptation approaches. We assess the changes to soil salinity at a managed dike realignment project prior to the transformation from a diked terrestrial environment to an estuarine environment. Baseline data are compared to conditions following 8-10 months of intermittent flooding at spring tides. Results show that an increase in salinity occurred over the entire site in the shallow subsurface, with the most significant contamination occurring in low-lying areas. Bulk soil electrical conductivity (salinity proxy) measured from geophysical surveys increased from the previous freshwater condition of ∼300 μS/cm to over 6000 μS/cm following <20 flood events, while successive flooding resulted in increased soil moisture as infiltrated floodwater propagated to greater depths. Sediment deposition occurred at high rates, with up to 4 cm of sediment deposited per flood, converting much of the previously cultivated land into tidal mudflats. Deeper sediments and groundwater (i.e., >1.8 m depth) were not impacted over the time scale of this research. This study demonstrates that intermittent shallow flooding can rapidly increase moisture content and soil salinity in surficial sediments and, in turn, adversely impact conditions suitable for agricultural crop production. The realignment zone serves as an engineered analog of coastal flooding, presenting an opportunity to investigate how low-lying coastal environments may experience regular flooding in the future due to sea-level rise and intensifying coastal storms.

This review article focuses on mental health implications of climate change. Global warming is likely to cause the severe widespread emergencies: extreme heat, droughts, wildfires, water-related disasters (i.e., flooding, hurricanes and coastal storms), extreme snow, severe thunderstorms and tornadoes. Rising temperatures, sea level rise and extreme weather events have led to secondary and tertiary consequences, e.g., social disruption, impoverishment and population displacement. Mental health risks of climate change include greater stress, stressrelated disorders, anxiety, despair, depression, and suicidal ideation. Those risks can stem from climate-related natural disasters (e.g., extreme weather events), slower moving events (e.g., drought), or concern about the phenomenon of climate change itself. A focus on the impact of climate change on mental health can help enhance the understanding of factors that strengthen psychosocial resilience and adaptation, as well as design tailor-made local interventions. Proper psychosocial adaptation strategies for the upcoming mental health challenges of climate change require development of social capital and strengthening of institutional systems.

Changes in temperature, precipitation, sea level, and coastal storms will likely increase the vulnerability of infrastructure across the USA. Using models that analyze vulnerability, impacts, and adaptation, this paper estimates impacts to railroad, roads, and coastal properties under three infrastructure management response scenarios: No Adaptation; Reactive Adaptation, and Proactive Adaptation. Comparing damages under each of these potential responses provides strong support for facilitating effective adaptation in these three sectors. Under a high greenhouse gas emissions scenario and without adaptation, overall costs are projected to range in the $100s of billions annually by the end of this century. The first (reactive) tier of adaptation action, however, reduces costs by a factor of 10, and the second (proactive) tier reduces total costs across all three sectors to the low $10s of billions annually. For the rail and road sectors, estimated costs for Reactive and Proactive Adaptation scenarios capture a broader share of potential impacts, including selected indirect costs to rail and road users, and so are consistently about a factor of 2 higher than prior estimates. The results highlight the importance of considering climate risks in infrastructure planning and management.

The impacts of climate change on ecosystems are manifested in how organisms respond to episodic and continuous stressors. The conversion of coastal forests to salt marshes represents a prominent example of ecosystem state change, driven by the continuous stress of sea-level rise (press), and episodic storms (pulse). Here, we measured the rooting dimension and fall direction of 143 windthrown eastern red cedar (Juniperus virginiana) trees in a rapidly retreating coastal forest in Chesapeake Bay (USA). We found that tree roots were distributed asymmetrically away from the leading edge of soil salinization and towards freshwater sources. The length, number, and circumference of roots were consistently higher in the upslope direction than downslope direction, suggesting an active morphological adaptation to sea-level rise and salinity stress. Windthrown trees consistently fell in the upslope direction regardless of aspect and prevailing wind direction, suggesting that asymmetric rooting destabilized standing trees, and reduced their ability to withstand high winds. Together, these observations help explain curious observations of coastal forest resilience, and highlight an interesting nonadditive response to climate change, where adaptation to press stressors increases vulnerability to pulse stressors.

In 2012, Hurricane Sandy hit the East Coast of the United States, creating widespread coastal flooding and over $60 billion in reported economic damage. The potential influence of climate change on the storm itself has been debated, but sea level rise driven by anthropogenic climate change more clearly contributed to damages. To quantify this effect, here we simulate water levels and damage both as they occurred and as they would have occurred across a range of lower sea levels corresponding to different estimates of attributable sea level rise. We find that approximately $8.1B ($4.7B-$14.0B, 5th-95th percentiles) of Sandy's damages are attributable to climate-mediated anthropogenic sea level rise, as is extension of the flood area to affect 71 (40-131) thousand additional people. The same general approach demonstrated here may be applied to impact assessments for other past and future coastal storms.

From microbes to humans, habitat structural complexity plays a direct role in the provision of physical living space, and increased complexity supports higher biodiversity and ecosystem functioning across biomes. Coastal development and the construction of artificial shorelines are altering natural landscapes as humans seek socio-economic benefits and protection from coastal storms, flooding and erosion. In this study, we evaluate how much structural complexity is missing on artificial coastal structures compared to natural rocky shorelines, across a range of spatial scales from 1 mm to 10 s of m, using three remote sensing platforms (handheld camera, terrestrial laser scanner and uncrewed aerial vehicles). Natural shorelines were typically more structurally complex than artificial ones and offered greater variation between locations. However, our results varied depending on the type of artificial structure and the scale at which complexity was measured. Seawalls were deficient at all scales (approx. 20-40% less complex than natural shores), whereas rock armour was deficient at the smallest and largest scales (approx. 20-50%). Our findings reinforce concerns that hardening shorelines with artificial structures simplifies coastlines at organism-relevant scales. Furthermore, we offer much-needed insight into how structures might be modified to more closely capture the complexity of natural rocky shores that support biodiversity.

Extreme weather events (EWE) are expected to increase as climate change intensifies, leaving coastal regions exposed to higher risks. South Florida has the highest HIV infection rate in the United States, and disruptions in clinic utilization due to extreme weather conditions could affect adherence to treatment and increase community transmission. The objective of this study was to identify the association between EWE and HIV-clinic attendance rates at a large academic medical system serving the Miami-Dade communities. The following methods were utilized: (1) Extreme heat index (EHI) and extreme precipitation (EP) were identified using daily observations from 1990-2019 that were collected at the Miami International Airport weather station located 3.6 miles from the studied HIV clinics. Data on hurricanes, coastal storms and flooding were collected from the National Oceanic and Atmospheric Administration Storms Database (NOAA) for Miami-Dade County. (2) An all-HIV clinic registry identified scheduled daily visits during the study period (hurricane seasons from 2017-2019). (3) Daily weather data were linked to the all-HIV clinic registry, where patients' 'no-show' status was the variable of interest. (4) A time-stratified, case crossover model was used to estimate the relative risk of no-show on days with a high heat index, precipitation, and/or an extreme natural event. A total of 26,444 scheduled visits were analyzed during the 383-day study period. A steady increase in the relative risk of 'no-show' was observed in successive categories, with a 14% increase observed on days when the heat index was extreme compared to days with a relatively low EHI, 13% on days with EP compared to days with no EP, and 10% higher on days with a reported extreme weather event compared to days without such incident. This study represents a novel approach to improving local understanding of the impacts of EWE on the HIV-population's utilization of healthcare, particularly when the frequency and intensity of EWE is expected to increase and disproportionately affect vulnerable populations. More studies are needed to understand the impact of EWE on routine outpatient settings.

Seawater intrusion (SWI) is influenced by a variety of coastal phenomena, such as sea level rise (SLR), inundation of low-lying coastal regions, coastal storms, recharge rate variations, and pumping-induced saltwater upconing. Quantification of the influence of heterogeneity in the hydraulic conductivity field on SWI combined with SLR, land-surface inundation, and recharge rate variations in an unconfined aquifer is the main objective of the present study. The principal SWI indicators used in this study are length of the SWI wedge, seawater volume, and weighted average transition zone width. Characterized by the hydraulic conductivity field variance (σ), the longitudinal correlation length (λ), the type of SLR (gradual or instantaneous SLR), the land-surface inundation consideration, and the recharge rate variations, 72 scenarios have been introduced, and for each of them, 50 sets of heterogeneous hydraulic conductivity fields have been generated. Based on two approaches, namely ensemble Monte-Carlo and a Bayesian framework, it is demonstrated that: (1) the land-surface inundation consideration increases the SWI wedge length and the seawater volume regardless of the type of SLR, while it decreases the weighted average transition zone width in gradual SLR scenarios; (2) λ has a more significant impact on SWI characteristics compared to σ; (3) increasing the degree of aquifer heterogeneity results in larger effective dispersion values; (4) Numerical bootstrapping suggests that the introduced Bayesian framework could be adopted as an alternative to computationally demanding methods such as bootstrapping for stochastic analysis of SWI; (5) Reliability analysis indicates the general belief that considering the heterogeneity decreases the SWI wedge length and the seawater volume, while increases the transition zone width compared to the homogeneous modeling is associated with huge amounts of uncertainty proportional to the aquifer heterogeneity itself; and (6) the results show that the impact of heterogeneity on the SWI indicators is similar under different recharge rates.

Coastal storms are highly unpredictable phenomena, frequently changing their characteristics and directly linked to global climate changes. They result in an intensive erosion processes and, are now a serious concern for the communities inhabiting the littoral zones. However, owing to the technical difficulties in registering morphological changes on cliff coasts, most short-term monitoring systems, analyses, and models have been implemented primarily along the dune coasts. Notwithstanding these difficulties, the changes on cliff coasts have been investigated quantitatively in order to properly identify the mechanisms controlling those phenomena. Here, we report on three soft-cliff systems in the southern Baltic Sea that were monitored with the use of terrestrial laser scanner (TLS) technology. A time series of thirteen topographic surveys were generated over a period of two years (12.2016-04.2018) and presented as coastal profiles with 50 meter spacing.