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The Sendai Framework for Disaster Risk Reduction develops and implements strategies to reduce disaster risks and can be used as a pedagogical tool to improve knowledge of natural hazards. From an early age, individuals can contribute positively to natural hazard mitigation and this is supported by research conducted in schools in countries like Thailand, Vietnam and Indonesia. Our research aims to explore undergraduate university student engagement and learning of natural hazards through real-world data analysis, risk assessment, developing adaptation and mitigation strategies and effective stakeholder communication in a region, while building students' knowledge about the various hazards affecting an area. Throughout a series of tutorials and assignments, students were asked to explain a specified hazard, identify existing risks, explore adaptation and mitigation strategies and develop a stakeholder communication tool. Overall, students performed well in each individual assignment, getting marks between 14-18 out of 20. Assignment 4, in which students had to create a communication tool to report their findings to a stakeholder, such as a governmental agency, was the one where students received the highest marks. Students' feedback at the end of the assignments was positive; most of them felt engaged and that the series of assignments enhanced their critical thinking skills.

The partition coefficients ([K.sub.D]) guiding the uptake of Mg and Sr in the low-Mg calcite valves of ostracodes in Australian saline lakes have been reviewed in line with new information on the bicarbonate content and the [alpha]Mg/[alpha]Ca of the ambient waters. Strongly alkaline and very high [alpha]Mg/[alpha]Ca (>>20) waters cause the partition coefficients of ostracodes to differ significantly from those found in other lakes with lower [alpha]Mg/[alpha]Ca values. Water salinity does not affect the uptake of Mg or Sr in ostracode valves, whereas the [alpha]HC[O.sup.-.sub.3] of the water strongly correlates to [K.sub.D][Sr], with high [alpha]HC[O.sup.-.sub.3] resulting in a significant [K.sub.D][Sr] decrease. doi: 10.1130/G30235.1

The Sendai Framework for Disaster Risk Reduction develops and implements strategies to reduce disaster risks and can be used as a pedagogical tool to improve knowledge of natural hazards. From an early age, individuals can contribute positively to natural hazard mitigation and this is supported by research conducted in schools in countries like Thailand, Vietnam and Indonesia. Our research aims to explore undergraduate university student engagement and learning of natural hazards through real-world data analysis, risk assessment, developing adaptation and mitigation strategies and effective stakeholder communication in a region, while building students' knowledge about the various hazards affecting an area. Throughout a series of tutorials and assignments, students were asked to explain a specified hazard, identify existing risks, explore adaptation and mitigation strategies and develop a stakeholder communication tool. Overall, students performed well in each individual assignment, getting marks between 14-18 out of 20. Assignment 4, in which students had to create a communication tool to report their findings to a stakeholder, such as a governmental agency, was the one where students received the highest marks. Students' feedback at the end of the assignments was positive; most of them felt engaged and that the series of assignments enhanced their critical thinking skills. [ABSTRACT FROM AUTHOR]

The 2004 Indian Ocean tsunami and the 2011 Tōhoku earthquake and tsunami caused large-scale topographic changes in coastal areas. Whereas much research has focused on coastlines that have or had large human populations, little focus has been paid to coastlines that have little or no infrastructure. The importance of examining erosional and depositional mechanisms of tsunami events lies in the rapid reorganization that coastlines must undertake immediately after an event. A thorough understanding of the pre-event conditions is paramount to understanding the natural reconstruction of the coastal environment. This study examines the location of sediment erosion and deposition during the 2004 Indian Ocean tsunami event on the relatively pristine Phra Thong Island, Thailand. Coupled with satellite imagery, we use numerical simulations and sediment transportation models to determine the locations of significant erosion and the areas where much of that sediment was redeposited during the tsunami inundation and backwash processes. Our modeling approach suggests that beaches located in two regions on Phra Thong Island were significantly eroded by the 2004 tsunami, predominantly during the backwash phase of the first and largest wave to strike the island. Although 2004 tsunami deposits are found on the island, we demonstrate that most of the sediment was deposited in the shallow coastal area, facilitating quick recovery of the beach when normal coastal processes resumed. [ABSTRACT FROM AUTHOR]

Tsunami deposits preserved in the geological record provide a more comprehensive understanding of their patterns of frequency and intensity over longer timescales; but recognizing tsunami deposits can prove challenging due to post‐depositional changes, lack of contrast between the deposits and surrounding sedimentary layers, and differentiating between tsunami and storm deposition. Modern baseline studies address these challenges by providing insight into modern spatial distributions that can be compared with palaeotsunami deposits. This study documents the spatial fingerprint of grain size and foraminifera from Hasunuma Beach and the Kujukuri shelf to provide a basis from which tsunami deposits can be interpreted. At Hasunuma Beach, approximately 50 km east of Tokyo, the spatial distribution of three common proxies (foraminiferal taxonomy, foraminiferal taphonomy and sediment grain size) for tsunami identification were mapped and clustered using Partitioning Around Medoids cluster analysis. Partitioning Around Medoids cluster analysis objectively discriminated two coastal zones corresponding to onshore and offshore sample locations. Results show that onshore samples are characterized by coarser grain sizes (medium to coarse sand) and higher abundances of Pararotalia nipponica (27 to 63%) than offshore samples, which are characterized by finer grain sizes (fine to medium sand), lower abundances of Pararotalia nipponica (2 to 19%) and Ammonia parkinsoniana (0 to 10%), higher abundances of planktonics (15 to 58%) and species with fragile tests including Uvigerinella glabra. When compared to grain‐size and foraminiferal taxonomy, foraminiferal taphonomy; i.e. surface condition of foraminifera, a proxy not commonly used to identify tsunami deposits, was most effective in discriminating modern coastal zones (identified supratidal, intertidal and offshore environments) and determining sediment provenance for tsunami deposits at Kujukuri. This modern baseline study assists the interpretation of tsunami deposits in the geological record because it provides a basis for sediment provenance to be determined. [ABSTRACT FROM AUTHOR]

The 2004 Indian Ocean Tsunami and the 2011 Great East Japan earthquake and tsunami caused large-scale topographic changes in coastal areas. Whereas much research has focused on coastlines that have or had large human populations, little focus has been paid on coastlines that have little or no infrastructure. The importance of examining erosional and depositional mechanisms of tsunami events lies in the rapid reorganisation that coastlines must undertake immediately after an event. Through understanding the precursor conditions to this reorganisation is paramount to the reconstruction of the coastal environment. This study examines the locations of sediment erosion and deposition during the 2004 Indian Ocean Tsunami event on the relatively pristine Phra Thong Island, Thailand. Coupled with satellite imagery, we use numerical simulations and sediment transportation models to determine the locations of significant erosion and the areas where much of that sediment was redeposited during the tsunami inundation and backwash processes. Our modelling approach confirms that beaches on Phra Thong Island were significantly eroded by the 2004 tsunami, predominantly during the backwash phase of the first and largest wave to strike the island. Although 2004 tsunami sediment deposits are found on the island, we demonstrate that most of the sediment was deposited in the shallow coastal area, facilitating quick recovery of the beach when normal coastal processes resume. [ABSTRACT FROM AUTHOR]

Sediment records left by coastal hazards (e.g. tsunami and/or storms) may shed light on the sedimentary and hydrodynamic processes happening during such events. Modern onshore and offshore sediment samples were compared with the 2004 Indian Ocean Tsunami, three palaeotsunami and a 2007 storm deposit from Phra Thong Island, Thailand, to determine provenance relationships between these coastal overwash deposits. Sedimentological and stratigraphic characteristics are generally inadequate to discriminate tsunami and storm deposits so a statistical approach (including cluster analysis, principal component analysis and discriminant function analysis) was used based on grain size, mineralogy and trace element geochemistry. The mineral content and trace element geochemistry are statistically inadequate to distinguish the provenance of the modern storm and tsunami deposits at this site, but the mean grain size can potentially discriminate these overwash deposits. The 2007 storm surge deposits were most likely sourced from the onshore sediment environment whereas all four tsunami units statistically differ from each other indicating diverse sediment sources. Our statistical analyses suggest that the 2004 tsunami deposit was mainly derived from nearshore marine sediments. The uppermost palaeotsunami deposit was possibly derived from both onshore and nearshore materials while the lower palaeotsunami deposits showed no clear evidence of their sediment sources. Such complexity raises questions about the origin of the sediments in the tsunami and storm deposits and strongly suggests that local context and palaeogeography are important aspects that cannot be ignored in tsunami provenance studies. [ABSTRACT FROM AUTHOR]

Paleoclimate proxy reconstruction initiatives, such as the Australian component of the international paleoclimate synthesis effort: INTegration of Ice core, MArine and Terrestrial records (OZ-INTIMATE), are important as they provide evidence of past climatic conditions that are necessary to evaluate global General Circulation Models (GCMs). One of the key outputs from the OZ-INTIMATE project was the production of spatially-coherent, climatic reconstructions over the southern Maritime Continent, Australasia and the Southern Ocean. The OZ-INTIMATE results were presented as regional, "simplified patterns of temperature and effective precipitation" and those regions spanned a large enough area to contain several GCM grid boxes. Therefore, the "upscaling" of individual reconstructions (through OZ-INTIMATE) to a scale that was resolved by GCMs, presented an ideal opportunity for a direct comparison. This study uses the same "simplified patterns of temperature and effective precipitation" approach from OZ-INTIMATE on data from an ensemble of GCMs. The GCM data are taken from the Paleoclimate Modeling Intercomparison Project (PMIP) mid-Holocene (6000 years before present, 6 ka) and pre-industrial control (c1750 C.E., 0 ka) experiments. The synthesis presented here shows that, on the whole, the models and proxies agree on the differences in climate state for 6 ka relative to 0 ka, when they are insolation driven. The main disagreement between the models and proxies occurs over the Tropical West Pacific warm pool and arises from an intensification of an existing error (the "cold tongue bias"). This study also presents a mechanism whereby the strength of the Southern Hemisphere, mid-latitude westerly wind strength reduces but rainfall increases over the southern temperate zone of Australia. Such a mechanism may be useful for resolving disparities between different regional proxy records, and model simulations. Finally, after assessing the available datasets (model and proxy), opportunities for better model-proxy integrated research are presented. [ABSTRACT FROM AUTHOR]