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This paper presents a framework for a probabilistic hazard assessment for the multi-hazard seismic and tsunami phenomena (PSTHA). For this work, we consider a full-rupture event along the Cascadia Subduction Zone and apply the methodology to the study area of Seaside, Oregon, along the US Pacific Northwest coast. In this work, we show that the annual exceedance probabilities ( A E P ) of the tsunami intensity measures ( I M ) are qualitatively dissimilar to the IMs of the seismic ground motion in the study area. Specifically, the spatial gradients for the tsunami IM are much stronger across the length scale of the city owing to the physical differences of energy dissipation of the two mechanisms. Example results of probabilistic seismic hazard analysis (PSHA) and probabilistic tsunami hazard analysis (PTHA) are shown for three observation points in the study area of Seaside. For the seismic hazard, the joint mean annual rate of exceedance shows similar trends for the three observation points, even though there is a large scatter between P G A and S a ( T 1 = 0.3 s ) . For the tsunami hazard, the joint A E P of h max and ( M F ) max shows a high correlation between the two I M s in the study area. The joint A E P at each of the three observation points follows a particular Froude number ( F r ) due to the local site-specific conditions locally rather than the distributions of fault slips. The joint probability distribution of h max and ( M F ) max throughout the study region falls between 0.1 ≤ F r < 1.0 (i.e., the flow is subcritical) regardless of return interval (500-, 1,000-, and 2,500-yr). However, the peak of the joint probability distribution with respect to h max and ( M F ) max varies with the return interval, and the largest values of h max and ( M F ) max were observed with the highest return intervals (2,500 yr) as would be expected. The results of the PSTHA can be the basis for a probabilistic multi-hazard damage assessment and help to understand the uncertainties of the multi-hazard assessments.

Both mass (as a measure of body reserves) during breeding and adult survival should reflect variation in food availability. Those species that are adapted to less seasonally variable foraging niches and so where competition dominates during breeding, will tend to have a higher mass increase via an interrupted foraging response, because their foraging demands increase and so become more unpredictable. They will then produce few offspring per breeding attempt, but trade this off with higher adult survival. In contrast, those species that occupy a more seasonal niche will not gain mass because foraging remains predictable, as resources become superabundant during breeding. They can also produce more offspring per breeding attempt, but with a trade-off with reduced adult survival. We tested whether the then predicted positive correlation between levels of mass gained during seasonal breeding and adult survival was present across 40 species of tropical bird measured over a 10-year period in a West African savannah. We showed that species with a greater seasonal mass increase had higher adult survival, controlling for annual mass variation (i.e. annual variation in absolute food availability) and variation in the timing of peak mass (i.e. annual predictability of food availability), clutch size, body size, migratory status and phylogeny. Our results support the hypothesis that the degree of seasonal mass variation in birds is probably an indication of life history adaptation: across tropical bird species it may therefore be possible to use mass gain during breeding as an index of adult survival.