Lagoons are highly productive coastal features that provide a range of natural services that society values. Their setting within the coastal landscape leaves them especially vulnerable to profound physical, ecological, and associated societal disturbance from global climate change. Expected shifts in physical and ecological characteristics range from changes in flushing regime, freshwater inputs, and water chemistry to complete inundation and loss and the concomitant loss of natural and human communities. Therefore, managing coastal lagoons in the context of global climate change is critical. Although management approaches will vary depending on local conditions and cultural norms, all management scenarios will need to be nimble and to make full use of the spectrum of values through which society views these unique ecosystems. We propose that this spectrum includes pragmatic, scholarly, aesthetic, and tacit categories of value. Pragmatic values such as fishery or tourism revenue are most easily quantified and are therefore more likely to be considered in management strategies. In contrast, tacit values such as a sense of place are more difficult to quantify and therefore more likely to be left out of explicit management justifications. However, tacit values are the most influential to stakeholder involvement because they both derive from and shape individual experiences and beliefs. Tacit values underpin all categories of social values that we describe and can be expected to have a strong influence over human behavior. The articulation and inclusion of the full spectrum of values, especially tacit values, will facilitate and support nimble adaptive management of coastal lagoon ecosystems in the context of global climate change.

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Coastal Lagoons and Climate Change: Ecological and Social Ramifications in U.S. Atlantic and Gulf Coast Ecosystems

Tropical cyclone-generated storm surges are among the world's most deadly and destructive natural hazards. This paper provides the first comprehensive global review of tropical storm surge data sources, observations, and impacts while archiving data in SURGEDAT, a global database. Available literature has provided data for more than 700 surge events since 1880, the majority of which are found in the western North Atlantic (WNA), followed by Australia/Oceania, the western North Pacific (WNP), and the northern Indian Ocean (NIO). The Bay of Bengal (BOB) in the NIO consistently observes the world's highest surges, as this subbasin averages five surges ≥5 m per decade and has observed credible storm tide levels reaching 13.7 m. The WNP observes the highest rate of low-magnitude surges, as the coast of China averages 54 surges ≥1 m per decade, and rates are likely higher in the Philippines. The U.S. Gulf Coast observes the second highest frequency of both high-magnitude (≥5 m) and low-magnitude (≥1 m) surges. The BOB observes the most catastrophic surge impacts, as 59% of global tropical cyclones that have killed at least 5000 people occurred in this basin. The six deadliest cyclones in this region have each killed at least 140,000 people, and two events have killed 300,000. Storm surge impacts transportation, agriculture, and energy sectors in the WNA. Oceania experiences long-term impacts, including contamination of fresh water and loss of food supplies, although the highest surges in this region are lower than most other basins.

https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1002/2014RG000477

A review of tropical cyclone‐generated storm surges: Global data sources, observations, and impacts

This paper contributes to the understanding of disasters from the perspective of social media activities. We develop a measure based on Twitter activities that can be used to quantify the evolution of disasters and thus demonstrate temporal–spatial patterns of Twitter activities particularly near the coastline and in large urban areas during Hurricane Sandy. We also show a close relationship between hurricane damages and Twitter activities. Our findings suggest the potential of using social media activities for rapid damage assessment.

Using social media data to understand and assess disasters

Modelling reveals that Dubai in the Persian Gulf region, Tampa in Florida, and Cairns in Australia are at risk of extreme tropical cyclones—‘grey swan’ events—capable of inducing surge impact beyond anything experienced in the historical record.

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Grey swan tropical cyclones

Climate change is acknowledged as the largest threat to our societies in the coming decades, potentially affecting large and diverse groups of urban residents in this century of urbanization. As urban areas house highly diverse people with differing vulnerabilities, intensifying climate change is likely to shift the focus of discussions from a general urban perspective to who in cities will be affected by climate change, and how. This brings the urban equity question to the forefront. Here we assess how climate change events may amplify urban inequity. We find that heatwaves, but also flooding, landslides, and even mitigation and adaptation measures, affect specific population groups more than others. As underlying sensitivity factors we consistently identify socioeconomic status and gender. We synthesize the findings with regard to equity types – meaning outcome-based, process-oriented and context-related equity – and suggest solutions for avoiding increased equity and justice concerns as a result of climate change impacts, adaptation and mitigation.

/pdf/climate-change-equity-and-the-sustainable-development-goals-1ng203isxu.pdf

Climate change, equity and the Sustainable Development Goals: an urban perspective

Hurricane Katrina (23–30 August 2005) struck low-lying coastal plains particularly vulnerable to storm surge flooding. Maximum storm surges, overland flow depths, and inundation distances were measured along the Gulf Coast of Florida, Alabama, Mississippi and Louisiana. The vehicle based survey was complemented by inspections with the reconnaissance boat along the Gulf Coast and the Mississippi Barrier Islands. The storm surge peaked to the East of Katrina’s path exceeding 10 meters in several locations along the Mississippi coastline. The storm surge measurements show that the lower floors of specially designed buildings were damaged by the surge of seawater and associated wave action, while the upper floors sustained minimal wind damage. Furthermore, the storm surge measurements along New Orleans’s Lake shore indicate that the 17th Street Canal levee failed prior to overtopping. The land loss on the barrier islands resulted in an increased vulnerability of the US Gulf Coast to future hurricane storm surges.

Hurricane katrina storm surge distribution and field observations on the Mississippi Barrier Islands

Hurricane Katrina (August 23–30, 2005) was one of the costliest and deadliest hurricanes to ever strike the United States, impacting low-lying coastal plains particularly vulnerable to storm surge flooding. Maximum storm surges, overland flow depths, and inundation distances were measured along the Gulf Coast of Florida, Alabama, Mississippi, and Louisiana. The vehicle-based survey was complemented by inspections with the reconnaissance boat along the Gulf Coast and the Mississippi Barrier Islands. The survey covered both the impact on the built and the natural environments. The storm surge peaked to the east of Katrina’s path exceeding 10 m in several locations along the Mississippi coastline. The storm surge measurements show that the lower floors of specially designed buildings were damaged by the surge of seawater and associated wave action, while the upper floors sustained minimal wind damage. The storm surge measurements along New Orleans Lakeshore allowed the investigators to exclude overtopping as...

Hurricane Katrina Storm Surge Reconnaissance

Studies of binary particle mixtures provide useful insight into the effects of fine particles on the void ratio of natural multi-sized geomaterials. The relative amount of fine particles in a mixture significantly changes the void structure and influences the behavior of such materials. This paper presents complimentary experimental evaluations and numerical simulations that show how void ratios change non-linearly as additional fine particles are included in binary mixtures. Experimental results for a range of particle size ratios are presented. The paper also demonstrates that there are particular percentages of fine particles by weight at which the lowest values of void ratio are achieved. Loosely packed binary mixtures are simulated by a gravitational sphere packing method to further examine the effect of different weight percentages of fine particles on the void structure. The numerical studies are based on Monte-Carlo simulations wherein spherical particles are randomly packed. The complex pore structure obtained by random packing prevents any pre-defined or repetitive packing arrangements, which can lead to the computation of non- representative void ratio values. Results obtained from the numerical simulations are compared with experimental results and confirm the viability of the gravitational sphere packing method to efficiently reproduce realistic packed soil particle systems.

Size Effects on the Void Ratio of Loosely Packed Binary Particle Mixtures

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Geomaterial gradation influences on interface shear behavior

The objective of this study was to update the 1998 NCHRP Synthesis 254: Service Life of Drainage Pipe, which in turn updated the 1978 NCHRP Synthesis 50: Durability of Drainage Pipe. The study approach consisted of two primary thrusts. First, a survey of North American transportation agencies was performed to determine the current state of practice. Second, a literature review was performed to assess both the state of practice and the state of the art with regard to the subject topic. This study showed a diverse range of pipe types in common usage among the states, with concrete, corrugated galvanized steel, and high-density polyethylene (HDPE) pipes as the most common pipe types in use, followed by galvanized structural plate and polyvinyl chloride (PVC). Within the past 15 years there has been significant advancement in understanding the mechanisms of pipe degradation in service. Significant work has been done with respect to corrosion and the main factors that influence its development in concrete and metal pipes; that is, pH, resistivity, chloride, and sulfates. This has led to studies into how to retard or prevent corrosion by the use of thicker walls, better materials, coatings, and liners. Advances have also been made in a better understanding of abrasion and how it enhances the rate of degradation from corrosion, and how its damaging effects can be mitigated. There has also been effective research undertaken in understanding the time-dependent changes in mechanical properties of thermoplastic pipe, particularly slow crack growth and oxidative/chemical failure and how they can be controlled. Little recent advancement has been made in refining pipe service prediction models, even for the more common pipe types. However, with the combination of research on the degradation mechanisms, a better understanding of the progression of deterioration, tied in with greater sources of pipe performance data from agency pipe inventories, in future more rapid progress in improving these models should be possible.

Andrew Fuggle

Papers

Hurricane katrina storm surge distribution and field observations on the Mississippi Barrier Islands

Hurricane Katrina Storm Surge Reconnaissance

Size Effects on the Void Ratio of Loosely Packed Binary Particle Mixtures

Geomaterial gradation influences on interface shear behavior

Service Life of Culverts