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For coastal regions on the margin of a subduction zone, near-field megathrust earthquakes are the source of the most extreme tsunami hazards, and are important to handle properly as one aspect of any Probabilistic Tsunami Hazard Assessment (PTHA). Typically, great variability in inundation depth at any point is possible due to the extreme variation in extent and pattern of slip over the fault surface. In this context, we present an approach to estimating inundation depth probabilities (in the form of hazard curves at a set of coastal locations) that consists of two components. The first component uses a Karhunen-Loève expansion to express the probability density function (PDF) for all possible events, with PDF parameters that are geophysically reasonable for the Cascadia Subduction Zone (CSZ). It is then easy and computationally cheap to generate a large $N$ number of samples from this PDF; doing so and performing a full tsunami inundation simulation for each provides a brute force approach to estimating probabilities of inundation. However, to obtain reasonable results, particularly for extreme flooding due to rare events, $N$ would have to be so large as to make the tsunami simulations prohibitively expensive. The second component tackles this difficulty by using importance sampling techniques to adequately sample the tails of the distribution and properly re-weight the probability assigned to the resulting realizations, and by grouping the realizations into a small number of clusters that we believe will give similar inundation patterns in the region of interest. In this approach, only one fine-grid tsunami simulation need be computed from a representative member of each cluster. We discuss clustering based on proxy quantities that are cheap to compute over a large number of realizations, but that can identify a smaller number of clusters of realizations that will have similar inundation depths. The fine-grid simulations for each cluster representative can also be used to develop an improved strategy, in which these are combined with cheaper coarse-grid simulations of other members of the cluster. We illustrate the methodology by considering two coastal locations: Crescent City, CA and Westport, WA.

On 28 September, 2018, Indonesia was struck by a MW 7.5 strike-slip earthquake. An unexpected tsunami followed, inundating nearby coastlines leading to extensive damage. Given the traditionally non-tsunamigenic mechanism, it is important to ascertain if the source of the tsunami is indeed from coseismic deformation, or something else, such as shaking induced landsliding. Here we determine the leading cause of the tsunami is a complex combination of both. We constrain the coseismic slip from the earthquake using static offsets from geodetic observations and validate the resultant “coseismic-only” tsunami to observations from tide gauge and survey data. This model alone, while fitting some localized run-up measurements overall fails to reproduce both the timing and scale of the tsunami. We also model coastal collapses identified through rapidly acquired satellite imagery and video footage as well as explore the possibility of submarine landsliding using tsunami ray tracing. The tsunami model results from the landslide sources, in conjunction with the coseismic generated tsunami show a greatly improved fit to both tide gauge and field survey data. Our results highlight a case of a damaging tsunami that’s primary source is not seismic. Tsunamis of this nature, while less common, are difficult to provide warning for and are underrepresented in regional tsunami hazard analysis.

"We must paint the great Mormon story of our pioneers in mural decorations so that 'he who runs may read,'" remarked Minerva Teichert. When she created her pioneer panorama, Teichert attempted to do something different; whereas other Mormon artists had drawn on their personal pioneer experiences or sought inspiration from Church-approved publications regarding the trek, her visual inspiration came from the oral narratives she heard as a child. Because she used these narratives, Teichert portrayed the Mormon pioneer experience from a woman's perspective and voiced their experiences to male and non-Mormon audiences. Not only did Teichert offer a counterpoint to sanctioned church histories, she coded her paintings with specific messages for different audiences, which allowed her to reach multiple audiences through her paintings.

Incorporating risk assessment into public project appraisal makes sense when project risk is significantly correlated with uncertainty about national income. It is especially important in countries that specialize in particular agricultural or resource sectors. This report presents the following conclusions: (a) risk corrections can be substantial; (b) the intuition that risk is great for further investment in a crop or sector that constitutes a large part of a country's GNP is not invalid, but the effect may be offset by other forces in operation; (c) risk corrections can be negative because of a negative correlation between project return and GNP; (d) risk premia vary greatly across countries and sectors - so recognizing the risk correction needed for each project on its own merits makes more sense than including a common general risk premium in the rate of return required for all lending; (e) risk corrections are small for many sectors and countries - so efforts can be concentrated on the other categories, where the proposed treatment of risk makes a big difference; (f) risk affects investment projects in many different, subtle ways; and (g) resource requirements for this are not great.

World prices have traditionally been unstable, however, the authors'find thehe much publicized turbulence in world markets in the mid-1970's and early 1980's to have been more a statistical fluke - an unlucky chance sample - than the beginning of any longer term increase in market instability. Variability in world prices has been almost entirely transmitted to developing countries in the dollar value of their export unit values. However, it has not been fully transmitted to average producer prices. Producer prices have been buffered by real exchange rates, domestic marketing arrangements, and government intervention, but still the level of instability remains sizable - and is the dominant source of instability in crop revenues for most producers. Unless farmers are able to diffuse the risky returns from export crops, price variability may seriously impede the expansion of agricultural exports in many developing countries.