Of laws and limits: An ecological economic perspective on redressing the failure of contemporary global environmental governance

The persistent failures of international environmental governance initiatives to halt the degradation of the global commons are directly linked to the implicit worldview and assumptions fueling the proliferation of industrial society. These include an instrumental conception on non-human nature, rampant materialism, technological optimism, and an expansionary economics premised on the axiomatic necessity of unconstrained growth. Permeating contemporary environmental governance regimes, it is argued that these premises are fundamentally incompatible with the requirements of environmental sustainability. Proceeding from the perspective of ecological economics, it is further argued that achieving environmental sustainability in industrial society requires foremost that we restructure and constrain the scale of economic activities relative to global biocapacity. It is concluded that a scale-based approach to governing the environmental commons, operationalized by a strong world environment organization, offers at least a partial solution to this conundrum.     

System versus component response of a two-span reinforced concrete bridge system

A large-scale 20.5 m long asymmetric two-span reinforced concrete bridge was tested to failure using the shake table system at the University of Nevada Reno. Upon completion of testing, in depth analytical modeling was conducted to evaluate the accuracy of conventional methods in reproducing the bridge model response and to develop a model for further study. Utilizing the experimentally verified computer model, the system effect was investigated, comparing the system and response of individual bents as well as the response of several other bridge models. In comparing computational model of the shake table specimen and models of the individual bents with tributary mass, it was shown that for all of the columns in this study, there was generally not an increase in hysteretic energy or large displacement cycles from system response at given displacement demand. The response of the bents for each high amplitude test motion was also compared. It was shown that there were significant differences in the bent demands for a given excitation due to system effects. In addition to the shake table model, four bridge systems with a constant total lateral stiffness were used in a parametric study to determine the system effect. The symmetric and uniform versions of the bridge specimen were shown to be comparable in nonlinear performance to the bridge specimen for the same high amplitude demand. The failure progression of the bridge model and the analytical comparisons suggested that the reserve capacity from varied column heights could provide a beneficial substructure redundancy.     

Vitriclastic lithofacies from Macquarie Island (Southern Ocean): compositional influence on abyssal eruption explosivity in a dying Miocene spreading ridge

Macquarie Island is composed of a complete section of oceanic crust that formed in a slow-spreading mid-ocean ridge 2.0 to 3.5 km below sea level. Vitriclastic facies preserved on the island have both pyroclastic and hyaloclastic characteristics. Monomict hyaloclastic breccia facies are widespread across the island and are predominantly composed of near-primitive (~7.9 wt% MgO) subalkaline/transitional (~0.7 wt% K₂O) sideromelane shards and crystalline basalt clasts with low vesicularity (LV, < 15% vesicles). Breccias are thick bedded and structureless with matrix-supported angular pillow fragments, bomb-sized fluidal mini-pillows, and globular glass lapilli. Clasts are lithologically similar to interbedded pillow basalts and laterally grade into fine-grained sandstone facies. These sandstones are normal-graded, well-laminated, thin bedded, and interstratified with red pelagic mudstone. Lithofacies associations indicate that the hyaloclastic breccias were formed proximal to a source vent via quench-fragmentation, and subsequently reworked by ocean-bottom currents into distal epiclastic sandstone facies. During eruption, co-genetic pillow lava and hypabyssal intrusions mingled with the breccia, forming fluidal peperite. Rare polymict pyroclastic facies only occur in the highest stratigraphic levels and are mostly composed of highly vesicular (HV, 15–50% vesicles) sideromelane shards and crystalline basalt clasts with alkaline (~1.0 wt% K₂O) fractionated (~6.8% MgO) compositions. Minor lithic grains are composed of subalkaline (~0.7 wt% K₂O) to very highly alkaline (~1.7 wt% K₂O) LV sideromelane shards, and amphibole-bearing diabase. The pyroclastic facies contains medium to thick beds of lapilli-tuff that exhibit both reverse and normal grading, diffuse lamination, and planar-grain fabric. These beds are locally overlain by thin fine-grained tuff beds entirely composed of cuspate to very thin elongate bubble-wall shards. These characteristics indicate that explosive deep-marine eruptions produced high-density coarse-grained gravity flows that were covered by slower suspension settle-out of delicate bubble-wall shards. Stratigraphic relationships suggest that explosive eruptions started during the waning stages of more alkaline volcanism along the proto-Macquarie spreading center.     

Influence of road network and population demand assumptions in evacuation modeling for distant tsunamis

Tsunami evacuation planning in coastal communities is typically focused on local events where at-risk individuals must move on foot in a matter of minutes to safety. Less attention has been placed on distant tsunamis, where evacuations unfold over several hours, are often dominated by vehicle use and are managed by public safety officials. Traditional traffic simulation models focus on estimating clearance times but often overlook the influence of varying population demand, alternative modes, background traffic, shadow evacuation, and traffic management alternatives. These factors are especially important for island communities with limited egress options to safety. We use the coastal community of Balboa Island, California (USA), as a case study to explore the range of potential clearance times prior to wave arrival for a distant tsunami scenario. We use a first-in–first-out queuing simulation environment to estimate variations in clearance times, given varying assumptions of the evacuating population (demand) and the road network over which they evacuate (supply). Results suggest clearance times are less than wave arrival times for a distant tsunami, except when we assume maximum vehicle usage for residents, employees, and tourists for a weekend scenario. A two-lane bridge to the mainland was the primary traffic bottleneck, thereby minimizing the effect of departure times, shadow evacuations, background traffic, boat-based evacuations, and traffic light timing on overall community clearance time. Reducing vehicular demand generally reduced clearance time, whereas improvements to road capacity had mixed results. Finally, failure to recognize non-residential employee and tourist populations in the vehicle demand substantially underestimated clearance time.     

SOME APPLICATIONS OF COMPUTER CARTOGRAPHY TO THE STUDY OF COGNITIVE CONFIGURATIONS

Cartographic theory and techniques are applied to the study of environmental cognition in an urban setting. Cognitive configurations of Columbus, Ohio derived from nonmetric multidimensional scaling are analyzed by location. A distinction is made between the distortion, or average accuracy, and the fuzziness, or dispersion, of estimates associated with forty-nine location cues. Computer mapping techniques are used to portray the distortion and fuzziness of each of these cues individually, and then in the form of a composite map.     

The development of the Space Environment Viability of Organics (SEVO) experiment aboard the Organism/Organic Exposure to Orbital Stresses (O/OREOS) satellite

The Space Environment Viability of Organics (SEVO) experiment is one of two scientific payloads aboard the triple-cube satellite Organism/ORganic Exposure to Orbital Stresses (O/OREOS). O/OREOS is the first technology demonstration mission of the NASA Astrobiology Small Payloads Program. The 1-kg, 1000-cm³ SEVO cube is investigating the chemical evolution of organic materials in interstellar space and planetary environments by exposing organic molecules under controlled conditions directly to the low-Earth orbit (LEO) particle and electromagnetic radiation environment. O/OREOS was launched on November 19, 2010 into a 650-km, 72°-inclination orbit and has a nominal operational lifetime of six months. Four classes of organic compounds, namely an amino acid, a quinone, a polycyclic aromatic hydrocarbon (PAH), and a metallo-porphyrin are being studied. Initial reaction conditions were established by hermetically sealing the thin-film organic samples in self-contained micro-environments. Chemical changes in the samples caused by direct exposure to LEO radiation and by interactions with the irradiated microenvironments are monitored in situ by ultraviolet/visible/near-infrared (UV/VIS/NIR) absorption spectroscopy using a novel compact fixed-grating CCD spectrometer with the Sun as its light source. The goals of the O/OREOS mission include: (1) demonstrating key small satellite technologies that can enable future low-cost astrobiology experiments, (2) deploying a miniature UV/VIS/NIR spectrometer suitable for in-situ astrobiology and other scientific investigations, (3) testing the capability to establish a variety of experimental reaction conditions to enable the study of astrobiological processes on small satellites, and (4) measuring the chemical evolution of organic molecules in LEO under conditions that can be extrapolated to interstellar and planetary environments. In this paper, the science and technology development of the SEVO instrument payload and its measurements are described.     

The size distributions of nanoscale Fe‐Ni‐S droplets in Stardust melted grains from comet 81P/Wild 2

Abstract– To constrain the effects of capture modification processes, the size distribution of nanoscale refractory Fe‐Ni‐S inclusions (“droplets”) was measured in five allocations extracted from throughout the depth of Stardust Track 35. The Fe/S ratio has been previously shown to increase significantly with penetration depth in this track, suggesting increasing capture‐related modification along the track. Astronomical image analysis tools were employed to measure the sizes of more than 8000 droplets from TEM images, and completeness simulations were used to correct the distribution for detection bias as a function of radius. The size distribution characteristics are found to be similar within independent regions of individual allocations, demonstrating uniformity within grains. The size distribution of the Fe‐Ni‐S droplets in each allocation is dominated by a mode near 11 nm, but is coarse‐skewed and leptokurtic with a mean of ～17 nm and a standard deviation of ～9 nm. The size distribution characteristics do not vary systematically with penetration depth, despite the strong trend in bulk Fe/S ratio. This suggests that the capture modification process is not primarily responsible for producing the morphology of these nanoscale droplets. The Stardust Track 35 droplet size distribution indicates slightly smaller sizes, but otherwise resembles those in carbonaceous chondrite Acfer 094, and chondritic porous interplanetary dust particles that escaped nebular annealing of sulfides. The size distribution of metal‐sulfide beads in Stardust’s quenched melted‐grain emulsions appears to be inherited from the size distribution of unmelted sulfide mineral grains in comet‐dust particles of chondritic character.     

Correction to: Beat-the-wave evacuation mapping for tsunami hazards in Seaside,Oregon, USA

Natural Hazards - Due to a procedural error in construction of Figs.&;nbsp;8 and 9, listed minimum speeds to beat the tsunami wave in areas of Seaside seaward of Neawanna Creek are too high. The...