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21.
We examine the participation of stakeholders in the rule-making process leading to the design of the US Clean Power Plan (CPP), which was the cornerstone regulation developed during the Obama administration to lower GHG emissions from power plants in the US. Using publicly available information, we identify the core stakeholders that participated in the different stages of the rulemaking process, from the early draft of the rule to its publication in final form, and examine variables that could help explain their decisions to litigate, either against or in favour of the final version of the rule. We show that the ‘pro-CPP’ stakeholders were (a) more likely to participate during the early stages of the rule-making process, attending meetings with the Environmental Protection Agency (EPA) staff to discuss rule content, and (b) less likely to get involved during the litigation process. ‘Anti-CPP’ stakeholders, on the other hand, did the opposite, being in general less active during the rulemaking stages, and more active during the litigation stage. However, we also find that the ‘anti-CPP’ stakeholders were more tightly organized as a coalition when compared to the ‘pro-CPP’ stakeholders throughout the process (even in the early stages when they participated less). Our results shed new light on the way advocacy coalitions operate in the climate policy subsystem in the US, and help inform debates about the likelihood of conflict and cooperation across a variety of environmental policy topics.

Key policy insights

  • The design of the Clean Power Plan was a long and contentious process in which ‘Pro’ and ‘Anti-CPP’ coalitions operated to support and undermine the rule, respectively.

  • ‘Pro-CPP’ stakeholders were more active in meetings organized to discuss the CPP with EPA staff, and in submitting written comments.

  • ‘Anti-CPP’ stakeholders were more active during litigation, in response to perceived EPA overreach in designing the rule and negative financial impacts on states’ economies.

  • Joint participation by ‘Anti-CPP’ stakeholders in meetings conveyed by the EPA to discuss the potential content of the rule helps explain their joint litigation efforts, which hints at their considerable capacity to self-organize as a coalition throughout the process.

  相似文献   
22.
Enxoé is a small temporary river with a flushy regime, which flash floods carry significant loads to the reservoir. As a result, the reservoir, which supplies 25,000 inhabitants, exhibits a high trophic state and cyanobacteria blooms since its construction in 1998, with water abstractions requiring extensive treatment. This study aimed to understand the contribution of flash floods to the Enxoé’s reservoir high trophic state using a modeling approach. This was the first time the river was monitored and that a modeling study was carried out. The MOHID-Land model was implemented to assess the water path in the catchment, and was integrated with field data to compute river loads. Results confirmed the importance of flash events. During flash floods, water properties were determined by soil surface and river bottom wash out, and depended mostly on the flush sequence and intensity. Model simulations showed that soil surface permeability reduction was an important factor regulating surface runoff while soil moisture was low. The first flood after the dry period contributed to 2% of the yearly discharge, 3% of yearly N load, and 7% of the yearly P loads. Winter floods contribution differed, producing 10% of both yearly discharge and loads. However, concentration of particulate matter and organic compounds in the first flood were one order of magnitude higher than in winter floods. This was due to river bottom resuspension and erosion of riparian areas, representative dynamics of a flushy regime. During subsequent winter floods, nutrient concentrations tended to remain constant as the watershed surface and respective soils were washed. Further work should link a watershed model to a reservoir model to depict the flood impact in the reservoir, and test management strategies to reduce the reservoir trophic state.  相似文献   
23.
Intersexuality has been widely reported in crustaceans with several mechanisms being directly or indirectly held responsible for its occurrence, amongst which pollution. No mechanistic relationship between metals and intersex has ever been established. Also the incidence of intersex in populations of the same invertebrate species in a latitudinal gradient has never been studied so far. Three populations (Iceland, Scotland and Portugal) of the amphipod Echinogammarus marinus were scrutinized. Intersex females from Iceland registered the highest fecundity loss. Only in Scottish samples females with two genital papillae and males with only one genital papillae were observed. Nevertheless, water, biota and sediment samples pointed to equivalent metal levels, and in consonance the prevalence of intersex was not significantly different between locations. An unequivocal relationship between metal presence and intersex induction cannot be presented, but our results advocate the potential role of metals as a direct cause of intersexuality in E. marinus.  相似文献   
24.
The South Pacific Ocean is a key driver of climate variability within the Southern Hemisphere at different time scales. Previous studies have characterized the main mode of interannual sea surface temperature (SST) variability in that region as a dipolar pattern of SST anomalies that cover subtropical and extratropical latitudes (the South Pacific Ocean Dipole, or SPOD), which is related to precipitation and temperature anomalies over several regions throughout the Southern Hemisphere. Using that relationship and the reported low predictive skill of precipitation anomalies over the Southern Hemisphere, this work explores the predictability and prediction skill of the SPOD in near-term climate hindcasts using a set of state-of-the-art forecast systems. Results show that predictability greatly benefits from initializing the hindcasts beyond the prescribed radiative forcing, and is modulated by known modes of climate variability, namely El Niño-Southern Oscillation and the Interdecadal Pacific Oscillation. Furthermore, the models are capable of simulating the spatial pattern of the observed SPOD even without initialization, which suggests that the key dynamical processes are properly represented. However, the hindcast of the actual phase of the mode is only achieved when the forecast systems are initialized, pointing at SPOD variability to not be radiatively forced but probably internally generated. The comparison with the performance of an empirical prediction based on persistence suggests that initialization may provide skillful information for SST anomalies, outperforming damping processes, up to 2–3 years into the future.  相似文献   
25.
Deliberated dental modifications and mutilations are known since prehistoric times. The Mayas and other ancient cultures in Mesoamerica were considered pioneers of such practice. The evidences of therapeutic intervention, however, are still poorly documented and credible examples are extremely scarce. One of the burials excavated at the locality of La Mina (Michoacan, Mexico) corresponds to a 30-35 year old male individual named Alvaro, who presented a well-marked dental deformation. Moreover, Alvaro had a quite deep and symmetrical perforation in the upper right canine–a treatment similar to the procedure of endodontics or root canal. The archaeological context of Alvaro’s habitat was dated using the archaeomagnetic method applied to pottery samples unambiguously correlated to the burial. The analysis supplied a time interval between 647 and 825 AD suggesting the first evidence of complex dental practice in the Americas.  相似文献   
26.
The Sunsás–Aguapeí province (1.20–0.95 Ga), SW Amazonian Craton, is a key area to study the heterogeneous effects of collisional events with Laurentia, which shows evidence of the Grenvillian and Sunsás orogens. The Sunsás orogen, characterized by an allochthonous collisional-type belt (1.11–1.00 Ga), is the youngest and southwesternmost of the events recorded along the cratonic fringe. Its evolution occurred after a period of long quiescence and erosion of the already cratonized provinces (>1.30 Ga), that led to sedimentation of the Sunsás and Vibosi groups in a passive margin setting. The passive margin stage was roughly contemporary with intraplate tectonics that produced the Nova Brasilândia proto-oceanic basin (<1.21 Ga), the reactivation of the Ji-Paraná shear zone network (1.18–1.12 Ga) and a system of aborted rifts that evolved to the Huanchaca–Aguapeí basin (1.17–1.15 Ga). The Sunsás belt is comprised by the metamorphosed Sunsás and Vibosi sequences, the Rincón del Tigre mafic–ultramafic sill and granitic intrusive suites. The latter rocks yield εNd(t) signatures (?0.5 to ?4.5) and geochemistry (S, I, A-types) suggesting their origin associated with a continental arc setting. The Sunsás belt evolution is marked by “tectonic fronts” with sinistral offsets that was active from c. 1.08 to 1.05 Ga, along the southern edge of the Paraguá microcontinent where K/Ar ages (1.27–1.34 Ga) and the Huanchaca–Aguapeí flat-lying cover attest to the earliest tectonic stability at the time of the orogen. The Sunsás dynamics is coeval with inboard crustal shortening, transpression and magmatism in the Nova Brasilândia belt (1.13–1.00 Ga). Conversely, the Aguapeí aulacogen (0.96–0.91 Ga) and nearby shear zones (0.93–0.91 Ga) are the late tectonic offshoots over the cratonic margin. The post-tectonic to anorogenic stages took place after ca. 1.00 Ga, evidenced by the occurrences of intra-plate A-type granites, pegmatites, mafic dikes and sills, as well as of graben basins. Integrated interpretation of the available data related to the Sunsás orogen supports the idea that the main nucleus of Rodinia incorporated the terrains forming the SW corner of Amazonia and most of the Grenvillian margin, as a result of two independent collisional events, as indicated in the Amazon region by the Ji-Paraná shear zone event and the Sunsás belt, respectively.  相似文献   
27.
The role of oceanic tide, wind stress, freshwater river inflows, and waves in the long-term circulation and residence time in óbidos Lagoon is investigated using a sensitivity analysis carried out by means of a two-dimensional model. MOHID modeling system coupled to Steady-State Spectral Wave model for simulate óbidos Lagoon circulation were implemented. For residence time calculus, a Lagrangian transport model was used. Tidal forcing is shown to be the dominant forcing, although storm waves must be considered to simulate accurately the long-term circulation. Tidal forcing enhances a spatial distribution in water residence time. Renewal time scales varies from values of 2 days in the near-ocean areas and 3 weeks in the inner areas. Freshwater river inflows decrease the residence time, while waves increase. In heavy rain periods, the water residence time decreases by about 40% in the upper lagoon. When wave forcing is considered, the residence time increases between 10% and 50% depending on lagoon area. The increase in residence time is explained by the sea level rise within lagoon (~1 m above average lagoon sea level) during storm wave periods. Average residence time is 16 days for tidal forcing, 9 days when the rivers are included (wet period), and 18 days when the waves are considered.  相似文献   
28.
A detailed observational study of the solar photospheric lithium feature has been carried out with emphasis on center-limb observations, continuum location, possible effects of telluric lines, effects of blending by atomic and molecular lines, and decomposition of the solar spectrum around λ6707 Å.  相似文献   
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