Climate change vulnerability and social development for remote indigenous communities of South Australia

There is a strong contemporary research and policy focus on climate change risk to communities, places and systems. While the need to understand how climate change will impact on society is valid, the challenge for many vulnerable communities, especially some of the most marginalised, such as remote indigenous communities of north-west South Australia, need to be couched in the context of both immediate risks to livelihoods and long-term challenges of sustainable development. An integrated review of climate change vulnerability for the Alinytjara Wilurara Natural Resources Management region, with a focus on the Anangu Pitjantjatjara Yankunytjatjara lands, suggests that targeted analysis of climate change impacts and adaptation options can overlook broader needs both for people and the environment. Climate change will add to a range of complex challenges for indigenous communities, especially in relation to hazards, such as fire and floods, and local environmental management issues, especially in association with invasive species. To respond to future socio-ecological risk, some targeted responses will need to focus on climate change impacts, but there also needs to be a better understanding of what risk is already apparent within socio-ecosystems and how climate interacts with such systems. Other environmental, social and economic risks may need to be prioritised, or at least strongly integrated into climate change vulnerability assessments. As the capacity to learn how to adapt to risk is developed, the value attributed to traditional ecological knowledge and local indigenous natural resource management must increase, both to provide opportunities for strong local engagement with the adaptation response and to provide broader social development opportunities.     

Deaggregation of multi-hazard damages,losses, risks,and connectivity: an application to the joint seismic-tsunami hazard at Seaside,Oregon

This paper presents a methodology to deaggregate the results of a multi-hazard damage analysis by extending the traditional multi-hazard damage analysis to consider both population characteristics and independent hazards. The methodology is applied to the joint seismic-tsunami hazard at Seaside, Oregon, considering four infrastructure systems: (1) buildings, (2) transportation network, (3) electric power network and (4) water supply network. Damages to all infrastructure systems are evaluated, and the networked infrastructures are used to inform parcel connectivity to critical facilities. US Census data and a probabilistic housing unit allocation method are implemented to assign detailed household demographic characteristics at the parcel level. Six dimensions of deaggregation are introduced: (1) spatial, (2) hazard type, (3) hazard intensity, (4) infrastructure system, (5) infrastructure component, and (6) housing unit characteristics. The damages, economic losses and risks, and connectivity to critical facilities are deaggregated across these six dimensions. The results show that deaggregated economic loss and risk plots can allow community resilience planners the ability to isolate high-risk events, as well as provide insights into the underlying driving forces. Geospatial representation of the results allows for the identification of both vulnerable buildings and areas within a community and is highlighted by the spatial pattern of parcel disconnection from critical facilities. The incorporation of population characteristics provides an understanding of how hazards disproportionately impact population subgroups and can aide in equitable resilience planning.

     

Propagation of impact‐induced shock waves in porous sandstone using mesoscale modeling

Generation and propagation of shock waves by meteorite impact is significantly affected by material properties such as porosity, water content, and strength. The objective of this work was to quantify processes related to the shock‐induced compaction of pore space by numerical modeling, and compare the results with data obtained in the framework of the Multidisciplinary Experimental and Modeling Impact Research Network (MEMIN) impact experiments. We use mesoscale models resolving the collapse of individual pores to validate macroscopic (homogenized) approaches describing the bulk behavior of porous and water‐saturated materials in large‐scale models of crater formation, and to quantify localized shock amplification as a result of pore space crushing. We carried out a suite of numerical models of planar shock wave propagation through a well‐defined area (the “sample”) of porous and/or water‐saturated material. The porous sample is either represented by a homogeneous unit where porosity is treated as a state variable (macroscale model) and water content by an equation of state for mixed material (ANEOS) or by a defined number of individually resolved pores (mesoscale model). We varied porosity and water content and measured thermodynamic parameters such as shock wave velocity and particle velocity on meso‐ and macroscales in separate simulations. The mesoscale models provide additional data on the heterogeneous distribution of peak shock pressures as a consequence of the complex superposition of reflecting rarefaction waves and shock waves originating from the crushing of pores. We quantify the bulk effect of porosity, the reduction in shock pressure, in terms of Hugoniot data as a function of porosity, water content, and strength of a quartzite matrix. We find a good agreement between meso‐, macroscale models and Hugoniot data from shock experiments. We also propose a combination of a porosity compaction model (ε–α model) that was previously only used for porous materials and the ANEOS for water‐saturated quartzite (all pore space is filled with water) to describe the behavior of partially water‐saturated material during shock compression. Localized amplification of shock pressures results from pore collapse and can reach as much as four times the average shock pressure in the porous sample. This may explain the often observed localized high shock pressure phases next to more or less unshocked grains in impactites and meteorites.