Arctic sea ice data from a variety of historical sources have been synthesized into a database extending back to 1850 with monthly time‐resolution. The synthesis procedure includes interpolation to a uniform grid and an analog‐based estimation of ice concentrations in areas of no data. The consolidated database shows that there is no precedent as far back as 1850 for the 21 st century's minimum ice extent of sea ice on the pan‐Arctic scale. A regional‐scale exception to this statement is the Bering Sea. The rate of retreat since the 1990s is also unprecedented and especially large in the Beaufort and Chukchi Seas. Decadal and multidecadal variations have occurred in some regions, but their magnitudes are smaller than that of the recent ice loss. Interannual variability is prominent in all regions and will pose a challenge to sea ice prediction efforts.
With the pursuit for global competitiveness and economic growth, Chinese cities have recorded massive urban land expansion. This article examines the effects of development policies and economic restructuring on urban land expansion in China through a case study of Nanjing, representing the rapidly growing and globalizing coastal cities in China. Wei investigate the development process and changing contents of government policies, and analyze development zones and key projects as privileged, trait making, and even path‐breaking elements of the development process. We highlight the transition and paradox of the Chinese state in the urban development process, and the broad contexts underlying urban land expansion in Chinese cities. We see urban expansion in China as a process largely responding to top‐down policy change and economic transition initiated by the central government. We hold that the role of the state has to be analyzed to understand urban transformation and land expansion, moving beyond local factors of accessibility and feasibility. Development‐zone and project fevers, and lagging administrative reforms, however, have made Chinese cities heavy with debt and led to wasteful development, corruption, and social unrest in China.
One of the most significant climate change impacts on arctic urban landscapes is the warming and degradation of permafrost, which negatively affects the structural integrity of infrastructure. We estimate potential changes in stability of Russian urban infrastructure built on permafrost in response to the projected climatic changes provided by six preselected General Circulation Models (GCMs) participated in the most recent Climate Model Inter‐comparison Project (CMIP5). The analysis was conducted for the entire extent of the Russian permafrost‐affected area. According to our analysis a significant (at least 25%) climate‐induced reduction in the urban infrastructure stability throughout the Russian permafrost region should be expected by the mid‐21st century. However, the high uncertainty, resulting from the GCM‐produced climate projections, prohibits definitive conclusion about the rate and magnitude of potential climate impacts on permafrost infrastructure. Results presented in this paper can serve as guidelines for developing adequate adaptation and mitigation strategy for Russian northern cities.
New‐build development has become associated with the phase of gentrification that has taken shape since the mid‐1990s. This article examines the gentrification of Deep Deuce, a historically black neighborhood in Oklahoma City. An analysis of property sales identifies the major external agents involved and leads to a discussion of the area's racial turnover. Considering the relational aspects of place, specifically how the identity of Deep Deuce has been constructed in relation to the nearby area of Bricktown, provides new insights on the nature of changes affecting this neighborhood. Supplementing this with an examination of resistance to the gentrification of Deep Deuce shows how city neighborhoods can come to be defined by limited understandings of place, and how historic preservation efforts can generate symbolic capital and facilitate cultural appropriation. This article also contributes to the study of gentrification in smaller metropolitan areas.