Climate justice and global cities: Mapping the emerging discourses

Ever since climate change came to be a matter of political concern, questions of justice have been at the forefront of academic and policy debates in the international arena. Curiously, as attention has shifted to other sites and scales of climate change politics matters of justice have tended to be neglected. In this paper, we examine how discourses of justice are emerging within urban responses to climate change. Drawing on a database of initiatives taking place in 100 global cities and qualitative case-study research in Philadelphia, Quito and Toronto, we examine how notions of distributive and procedural justice are articulated in climate change projects and plans in relation to both adaptation and mitigation. We find that there is limited explicit concern with justice at the urban level. However, where discourses of justice are evident there are important differences emerging between urban responses to adaptation and mitigation, and between those in the north and in the south. Adaptation responses tend to stress the distribution of ‘rights’ to protection, although those in the South also stress the importance of procedural justice. Mitigation responses also stress ‘rights’ to the benefits of responding to climate change, with limited concern for ‘responsibilities’ or for procedural justice. Intriguingly, while adaptation responses tend to stress the rights of individuals, we also find discourses of collective rights emerging in relation to mitigation.     

Distribution and Abundance of Arsenic in the Soils and Sediments of O‘ahu,Hawai‘i

Lack of high-spatial-resolution soil and sediment arsenic data for Hawai‘i has generated substantial disagreement between researchers and regulators regarding the magnitude of natural levels of arsenic in Hawai‘i and rendered difficult the defining of areas of anthropogenically elevated arsenic. Our earlier research into the occurrence of arsenic in terrestrial and marine environments revealed widely disparate concentrations of arsenic with no apparent spatial pattern. To better understand the distribution and abundance of arsenic in soils and sediments of O‘ahu, we collected an additional 64 samples at locations chosen to represent different environments with varying degrees of human impact. We found surface arsenic values that ranged from 0.28 to 740 ppm with a median concentration of 8.1 ppm, which is above the global median of 5 ppm and US soil median of 5.2 ppm. Higher concentrations of arsenic (up to 913 ppm) were encountered at depth in soil cores. The median arsenic in streambed sediments from one of our earlier studies of 6.1 ppm was comparable to the conterminous US median of 6.3 ppm; however, we encountered arsenic concentrations as high as 43.9 ppm (median = 8.60 ppm, n = 75) in marine sediments in recent work off the leeward coast of O‘ahu. Overall, arsenic in the soils and sediments of O‘ahu is elevated relative to world and national values, but there still is no readily discernible pattern in the distribution of arsenic to explain these elevated values.     

Lateral variations in tectonic style across cross-strike discontinuities: an example from the Central Apennines belt (Italy)

In foreland thrust belts, abrupt lateral changes in tectonic style, structural–stratigraphic features, and topography usually occur across cross-strike faults. The Central Apennines of Italy offer an exceptional scenario of lateral variations in tectonic setting. Here, the Sangro Volturno oblique thrust ramp (SVOTR) represents the outer thrust front of the Pliocene–Quaternary foreland thrust system, confining southward the axial culmination of the orogen that occurs in the Central Apennines. We present an interpretation of the Pliocene–Quaternary evolution of this cross-strike fault through an integrated dataset including structural-geological mapping and subsurface onshore seismic reflection profiles. The interpretation of the structural framework is augmented by the analysis of low-temperature thermochronometers from 32 new sites extending across the subsurface transverse structure. As evidenced by seismic line interpretation, the localization and development of the SVOTR have been influenced by inherited extensional faults within a positive inversion tectonics context. The regional distribution of the maximum paleotemperature values across the SVOTR constrains the original extent of the allochthonous thrust sheet over all its hanging-wall and footwall blocks. The Pliocene–Quaternary thrusting and inversion of SVOTR caused the strong hanging-wall uplift, which brought to the complete erosion of the allochthonous units and the exhumation of the Adria units. The integrated analysis of low-temperature thermochronometers and structural evidence as applied in the study case can define the role of major cross-strike discontinuities in foreland thrust belts, by constraining and verifying their tectonics inversion significance and the amount of related exhumation.     

An efficient technique for pre-selecting low-redshift damped Lyα systems

The number of z ∼ 1 damped Lyα systems (DLAs, log  N (H  i ) ≥ 20.3) per unit redshift is approximately 0.1, making them relatively rare objects. Large, blind QSO surveys for low-redshift DLAs are therefore an expensive prospect for space-borne ultraviolet telescopes. Increasing the efficiency of these surveys by pre-selecting DLA candidates based on the equivalent widths (EWs) of metal absorption lines has previously been a successful strategy. However, the success rate of DLA identification is still only ∼35 per cent when simple EW cut-offs are applied, the majority of systems having 19.0 < log  N (H  i ) < 20.3. Here, we propose a new way to pre-select DLA candidates. Our technique requires high-to-moderate-resolution spectroscopy of the Mg  ii λ2796 transition, which is easily accessible from the ground for 0.2 ≲ z ≲ 2.4. We define the D -index, the ratio of the line equivalent width to velocity spread, and measure this quantity for 19 DLAs and eight sub-DLAs in archival spectra obtained with echelle spectrographs. For the majority of absorbers, there is a clear distinction between the D -index of DLAs compared with sub-DLAs (Kolmogorov–Smirnov probability = 0.8 per cent). Based on this pilot data sample, we find that the D -index can select DLAs with a success rate of up to 90 per cent, an increase in selection efficiency by a factor of 2.5 compared with a simple EW cut. We test the applicability of the D -index at lower resolution and find that it remains a good discriminant of DLAs for full width at half-maximum (FWHM) ≲ 1.5 Å. However, the recommended D -index cut-off between DLAs and sub-DLAs decreases with poorer resolution and we tabulate the appropriate D -index values that should be used with spectra of different resolutions.     

Studying Resource-Dependent Communities Through a Social-Ecological Lens? Examining Complementarity with Existing Research Traditions in Canada

This article explores the suitability of Ostrom and colleagues' social-ecological systems framework (SESF) for the study of resource-dependent communities in Canada. Through a broad literature about resource-dependent communities in Canada, three main approaches are identified, named staples research, rural development, and sustainability studies. Each of these research traditions is analyzed with regards to a common set of criteria – focus, scale, methods, treatment of institutions, and treatment of environmental dimensions. Research in each category is compared and contrasted with the SESF approach, to identify areas of overlap and divergence. Results indicate that the SESF is unlikely to provide additional benefit in terms of in-depth of social analysis, however, it does provide a unique contribution in terms of its coupled approach to conceiving social and ecological systems and its ability to operationalize these relationships through structured variables.     

Land surface coupling in regional climate simulations of the West African monsoon

Coupling of the Community Land Model (CLM3) to the ICTP Regional Climate Model (RegCM3) substantially improves the simulation of mean climate over West Africa relative to an older version of RegCM3 coupled to the Biosphere Atmosphere Transfer Scheme (BATS). Two 10-year simulations (1992–2001) show that the seasonal timing and magnitude of mean monsoon precipitation more closely match observations when the new land surface scheme is implemented. Specifically, RegCM3–CLM3 improves the timing of the monsoon advance and retreat across the Guinean Coast, and reduces a positive precipitation bias in the Sahel and Northern Africa. As a result, simulated temperatures are higher, thereby reducing the negative temperature bias found in the Guinean Coast and Sahel in RegCM3–BATS. In the RegCM3–BATS simulation, warmer temperatures in northern latitudes and wetter soils near the coast create excessively strong temperature and moist static energy gradients, which shifts the African Easterly Jet further north than observed. In the RegCM3–CLM3 simulation, the migration and position of the African Easterly Jet more closely match reanalysis winds. This improvement is triggered by drier soil conditions in the RegCM3–CLM3 simulation and an increase in evapotranspiration per unit precipitation. These results indicate that atmosphere–land surface coupling has the ability to impact regional-scale circulation and precipitation in regions exhibiting strong hydroclimatic gradients.     

The identification and interaction of network,intranetwork, and ephemeral-region magnetic fields

Network magnetic fields, ephemeral active regions, and intranetwork magnetic fields are illustrated and discussed in several contexts. First, they are presented in relation to the appearance and disappearance of magnetic flux. Second, their properties in common with all solar magnetic features are discussed. Third, their distinguishing characteristics are emphasized. Lastly, their interactions are illustrated.Network magnetic fields are no longer considered to be just the aged remnants of active regions. The network is the dynamic product of the merging and cancelling of intranetwork fields, ephemeral regions, and the remnants of active regions. Intranetwork fields are magnetic fields of mixed polarity that appear to originate continuously from localized source sites in between the network. The intranetwork magnetic fields are characterized by flow of successive fragments in approximately radial patterns away from their apparent source sites and by the relative weakness of their magnetic fields. Ephemeral active regions are small, new bipoles that grow as a unit or a succession of bipolar units and whose poles move in opposite directions from their apparent site of origin. Large ephemeral regions are not distinguishable from small active regions.Solar Cycle Workshop Paper.     

Cancer risks from exposure to vehicular air pollution: a household level analysis of intra-ethnic heterogeneity in Miami,Florida

Quantitative environmental justice (EJ) research has relied on aggregated data from census units to determine disproportionate hazard exposure. Additionally, variables typically used to analyze ethnic inequities in exposure (e.g., percent Hispanic) are too broad and assume a degree of homogeneity that may not exist, given the diversity of ethnic minority populations. We address these limitations through a study that utilizes primary household level survey data and cancer risk estimates from the National-Scale Air Toxics Assessment (NATA) to analyze intra-ethnic inequities in exposure to vehicular air pollutants in the Miami metropolitan area, Florida. Our analysis disaggregates the Hispanic category based on five characteristics (language proficiency, U.S. citizenship, nativity, unemployment status, and national origin) and finds that risk burdens are significantly higher for Hispanic respondents who are foreign-born, unemployed, and of Cuban origin. Findings highlight the advantages of downscaling EJ analyses to the household level and considering intra-ethnic heterogeneity in EJ research and policy.