Abstract

Based on the simulations of 22 CMIP5 models in combination with socio-economic data and terrain elevation data, the spatial distribution of risk levels of flood disaster and the vulnerability to flood hazards in China are projected under the RCP8.5 for the near term period (2016–2035), medium term period (2046–2065) and long term period (2080–2099), respectively. The results show that regions with high flood hazard levels are mainly located in Southeast China, while the vulnerability to flood hazards is high in eastern China. Under the RCP8.5 greenhouse gas emissions scenario, future high flood risk levels will mainly appear in the eastern part of Sichuan, in major part of East China, and in the provinces of Hebei, Beijing, and Tianjin. The major cities in Northeast China, some areas in Shaanxi and Shanxi, as well as the coastal areas in southeastern China will also encounter high flood risks. Compared with the baseline period, the regional flood risk levels will increase towards the end of the 21st century, although the occurrences of floods change little. Due to the coarse resolution of the climate models and the indistinct methodology for determining the weight coefficients, large uncertainty still exists in the projection of flood risks. Xu, Y., Zhang, B., Zhou, B.-T., et al., 2014. Projected flood risks in China based on CMIP5. Adv. Clim. Change Res. 5(2), doi: 10.3724/SP.J.1248.2014.057.

Abstract

A unique strategic opportunity beckons Bangladesh. Dhaka, the economic powerhouse of the country, stands on the cusp of a dramatic transformation that could make it much more prosperous and livable. Today, Dhaka is prone to flooding, congestion, and messiness, to a point that is clogging its growth. But toward its east, where two major highway corridors will one day intersect, is a vast expanse of largely rural land. And much of it is within 6 kilometers of the most valuable parts of the city. The time to make the most of this eastward opportunity is now. Many parts of East Dhaka are already being developed in a haphazard way at an alarmingly rapid pace. Private developers are buying land and filling it with sand so they can build and sell new houses and apartments. Canals and ponds are disappearing, and the few narrow roads crossing the area are being encroached by construction. This spontaneous development could soon make East Dhaka look like the messy western part of the city, and retrofitting it later will be more difficult and costlier than properly planning and developing it now. Toward Great Dhaka: A New Urban Development Paradigm Eastward seeks to analyze how the opportunity of East Dhaka could be realized. Using state-of-the-art modeling techniques, the study simulates population, housing, economic activity, and commuting times across the 266 unions that constitute Greater Dhaka. It does so under various scenarios for the development of East Dhaka, but always assessing the implications for the entire city. The simulations suggest that pursuing a strategic approach to the development of East Dhaka would make Greater Dhaka a much more productive and livable city than continuing with business as usual. Based on current trends, Greater Dhaka would have a population of 25 million in 2035 and an income per capita of US$8,000 at 2015 prices. However, embracing a strategic approach would add 5 million people to the city. And, it would be a more productive city, with nearly 1.8 million more jobs and an income per capita of more than US$9,200 at 2015 prices, enough to put Dhaka on the map of global cities. Document type: Book

Abstract

This paper presents the details of three scenarios -- leapfrog, lock-in, and lopsided -- that describe an illustrative set of technological states. Based largely on expert interviews, the paper argues that the technology outcomes are heavily attributable to the actions (or in some cases, inaction) of policy makers and incumbents. For each scenario, the paper presents descriptive levels of technology achievement and market outcomes for the energy, transport, and water sectors. One of the central differentiating features of the three scenarios is the extent to which governments perform their roles as enabling, that is, whether the policies are designed to help or hinder innovations that improve service levels, and distributive, that is, whether the policies are designed to ensure that multiple segments of society reap the rewards of innovation. A question raised as part of that theme is how countries can avoid lock-in, or how they might become derailed into a lopsided scenario. Some institutional behavioral markers of the scenarios were identified in these discussions and are noted in the paper. It is important to recognize that multiple combinations of these behaviors can lead to a lock-in or lopsided scenario. In addition to describing the scenarios in detail, the paper discusses the rationale for their creation, along with a brief discussion on the nature of uncertainty. The paper also describes the methodology employed in the creation of the scenarios, including expert interview methods and a day-long workshop. Document type: Book