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Abstract: Given the difficulty of earthquake forecast, Probabilistic Seismic Hazard Analysis (PSHA) has been a method to best estimate site-specific ground motion or response spectra in earthquake engineering and engineering seismology. In this paper, the first in-depth PSHA study for Taipei, the economic center of Taiwan with a six-million population, was carried out. Unlike the very recent PSHA study for Taiwan, this study includes the follow-up hazard deaggregation, response spectra, and the earthquake motion recommendations. Hazard deaggregation results show that moderate-size and near-source earthquakes are the most probable scenario for this city. Moreover, similar to the findings in a few recent studies, the earthquake risk for Taipei should be relatively high and considering this city''s importance, the high risk should not be overlooked and a potential revision of the local technical reference would be needed. In addition to the case study, some innovative Excel applications to PSHA are introduced in this paper. Such spreadsheet applications are applicable to geosciences research as those developed for data reduction or quantitative analysis with Excel''s user-friendly nature and wide accessibility. [Copyright &y& Elsevier]

This paper argues that climate change adaptation through strategic greenspace planning requires scholars and planners to think differently about what equity means in an urban greenspace context. We use the heat mitigation potential of greenspace and the case of Taipei Metropolis in Taiwan to assess challenges arising from thinking about fairness in terms of distribution of benefits from greenspace functions, as opposed to fairness in greenspace accessibility and availability. Urban greening to foster ‘resilient’ communities arguably deflects from – or even exacerbates – structural causes of vulnerability, with benefits accruing disproportionately to more affluent or empowered groups. Yet the need for practical action on climate threats in cities is urgent, and for heat, strategic greenspace use considered systematically across a city may mitigate effects through the cooling effect of vegetation. The challenge is thus to balance the justice concerns associated with urban greening with this tangible risk reduction potential. We undertake content analysis of articles from two Taiwanese newspapers – the Taipei Times and the China Post – to assess how heat and greenspace issues have been discussed in urban governance debates within Taipei. We suggest change adaptation through urban greening raises three challenges for equity thinking: (a) guiding planning and governance processes with scientific understanding of how greenspace functions are delivered, even in the face of urban development pressures and site-specific controversies; (b) tempering the social cohesion and practical deployment benefits of neighbourhood-level greening with the need for specific understanding at the city-wide level to most effectively realise ecosystem services; and (c) linking targeted adaptation actions with broader rationales for urban greening, whilst not diluting justice concerns. We caution that pragmatism towards all urban climate adaptation via greening as intrinsically ‘good’ must not serve as a blinder to the need for accompanying social policy measures to reduce unequal vulnerability to climate risks. [ABSTRACT FROM AUTHOR]

Recent studies have shown that structural damage exhibits stronger correlations with cumulative absolute velocity (CAV) than other ground motion intensity measures (e.g., PGA). This paper presents a CAV site-effect assessment for the Taipei areas for the first time. The study was based on more than 1200 strong-motion data from 47 major earthquakes that had occurred around Taiwan. The results show that the site effects are more conspicuous in the western Taipei than the eastern areas, and it is also obvious that the site effect is strong in locations close to the rims of the basin, where seismic waves could be easily reflected, refracted and superimposed. Subsequently, a map showing the areas in Taipei subject to severe CAV amplification and/or high variability was developed for site-effect microzonation for the study area, on the basis of CAV that was considered better correlated with structural damage under earthquake condition. [ABSTRACT FROM AUTHOR]

Summary: Deterioration of the quality of groundwater under urban areas has become a major environmental concern worldwide. This paper presents a pilot case study (in the Taipei urban area) using multiple stable isotopes ( and , and , and , and 87Sr/86Sr) with the aim of understanding the subsurface nature and environmental status of such areas. A previous study has already characterized Taipei shallow groundwaters as sulfate-rich in comparison to other Southeast Asian metropolitan cities. Our chemical measurements clarified that the arsenic is the important environmental concerns in the aquifers. Dual isotope approaches for nitrate and sulfate suggested these ions were sourced mainly from municipal sewage leaking from sewer pipes in urbanized area, while chemical fertilizers applied in the local agricultural fields partly contribute in the suburb area. Significant decreases in nitrate and sulfate concentrations due to denitrification and sulfate reduction were observed in some groundwaters, which induced increases in isotope ratios up to 24.9‰ for and 27.2‰ for . Nitrate groundwater pollution in the Taipei Basin is not a subject of serious concern (<44mg/L limit for for all analyzed samples) at the present time due to attenuation by denitrification. However, arsenic is preferentially released in groundwater (>100μg/L) in anoxic environment under which sulfate reduction occurs. The Sr isotope data suggested that the arsenic is derived from alluvial deposits of Oligocene–Miocene sedimentary rock origin. This study disclosed the complex causes of environmental changes in Taipei urban shallow groundwater. It is also important as an excellent case study demonstrating the efficient use of multiple isotope diagnosis in the urban groundwater environmental field. [ABSTRACT FROM AUTHOR]