Carbon emission trading and carbon taxes under uncertainties

The idea of market-based carbon emission trading and carbon taxes is gaining in popularity as a global climate change policy instrument. However, these mechanisms might not necessarily have a positive outcome unless their value reflects socioeconomic and environmental impacts and regulations. Moreover, the fact that they have various inherent exogenous and endogenous uncertainties raises serious concerns about their ability to reduce emissions in a cost-effective way. This paper aims to introduce a simple stochastic model that allows the robustness of economic mechanisms for emission reduction under multiple natural and human-related uncertainties to be analyzed. Unlike standard equilibrium state analysis, the model shows that the explicit introduction of uncertainties regarding emissions, abatement costs, and equilibrium states makes it almost impossible for existing market-based trading and carbon taxes to be environmentally safe and cost-effective. Here we propose a computerized multi-agent trading model. This can be viewed as a prototype to simulate an emission trading market that is regulated in a decentralized way. We argue that a market of this type is better equipped to deal with long-term emission reductions, their direct regulation, irreversibility, and “lock-in” equilibria.     

Propagation of brittle failure triggered by magma in Iceland

The architectures of normal faults at a divergent plate boundary in Iceland are examined by combining surface fault observations with cross-sectional studies at different structural levels to constrain a model of failure propagation. The structures of Holocene faults defining graben are analyzed to characterize the upper-most parts of ruptures. The shapes of faults resulting from growth and interaction of separate segments are used to better understand failure propagation inferred to occur in the intervening stages of displacement accumulation and lateral propagation. Pleistocene faults in volcanic sequences exhumed from 800 to 1000 m are analyzed to characterize deeper portions of failure that occurred beneath the central rift zone. Tertiary dikes exhumed from depths of 1300–1500 m are studied to infer how magma controls the failure initiation. Field studies in combination with a literature review indicate that the planar ruptures are likely to initiate at depth as magma-filled vertical fractures and lengthen upward and laterally. As failures propagate to higher crustal levels, they are likely to change into inclined normal faults. At near-surface levels, faults link with cooling joints and dilational fractures propagating downward from the surface. It is suggested that the inferred stages of fault propagation are characteristic for normal faults developed at spreading ridges.     

An assessment of changes in properties of steppe kurgan paleosoils in relation to prevailing climates over recent millennia

Comparative analysis of morphological and chemical properties of the soil chronosequence on Kastanozems soils in the steppe zone of the Russian Plain, which included paleosoils buried beneath kurgans erected ca. 2000 BC, AD 50, AD 200, and AD 1250 was performed to reconstruct the paleoenvironmental conditions in this archeologically important region. Paleoenvironmental dynamics were traced using the state of microbial communities of paleo and modern soils (including the dynamics of total and glucose-reactive biomass, and the abundance of microorganisms grown on selected media). We demonstrate that the share of the glucose-reactive microorganisms in the microbial community, the ecological–trophic structure, and oligotrophicity index might serve as indicators of the state of microbial communities and be used for paleoenvironmental reconstructions. The morphological–chemical and microbial properties confirm an arid period ca. 2000 BC, slightly wetter conditions ca. AD 50, and more humid conditions ca. AD 1250.     

Analogue modeling of overlapping spreading centers: insights into their propagation and coalescence

The propagation and segmentation of mid-ocean ridges is studied using centrifuged analogue models built with non-linear materials. The deformation of the brittle-ductile model is controlled by diapiric uprise of buoyant analogous asthenospheric material induced by a centrifugal body force. This linear upwelling laterally stretches the model mantle that, in turn, induces failure in the upper layer simulating the brittle crust. Arrays of fractures initiate within zones of high stress concentration above the diapir. Fractures propagate laterally in a direction perpendicular to the maximum tensile (the minimum principal) stress. Secondary tension cracks initiate in the vicinity of parent fracture tips. Through-going fractures that crosscut the model surface develop by short fractures propagating toward each other and coalescing in different types of patterns. The overlap, overstep and inclination of fractures developed at the initial stage of extension control their subsequent growth and coalescence. Non-overlapping sub-parallel fractures propagate along nearly straight paths and coalesce to produce a single planar fracture. If overlapping fractures are parallel, they propagate towards each other along curved paths that enclose an intervening elliptical core of intact material. Fracture curvature in this case results from crack–crack interaction and is similar to that of overlapping spreading centers (OSCs) observed along mid-ocean ridges. Overlapping non-parallel fractures tend to coalesce by one of their tips propagating sub-parallel to the spreading direction toward the other fracture. Such offsets can serve as models for the development of the orthogonal ridge-transform fault patterns common along mid-ocean ridges.     

Organic and trace metal contaminants in sediments and English sole tissues from Vancouver Harbour,Canada

As part of a multinational workshop on marine environmental quality, sediments were collected from seven sites in Vancouver Harbour and analyzed for polynuclear aromatic hydrocarbons (PAHs) and organochlorines (OCs), and for trace metals. English sole were collected from five sites, and muscle was analyzed for trace metals and liver for OCs. As expected, sediment PAH and OC concentrations and tissue OC concentrations were higher at sites east of the First Narrows, compared to the outer harbor and reference sites. Sediment PAH concentrations east of the First Narrows were similar to concentrations at moderately contaminated sites in Puget Sound, south of Vancouver Harbour. In contrast, concentrations of OCs in sediments and tissue were low to moderate, even at relatively contaminated sites within Vancouver Harbour. Although several trace metals in sediments were higher than in contaminated sediments from Puget Sound, trace metals measured in fish muscle were lower.     

Holocene Treeline History and Climate Change Across Northern Eurasia

Radiocarbon-dated macrofossils are used to document Holocene treeline history across northern Russia (including Siberia). Boreal forest development in this region commenced by 10,000 yr B.P. Over most of Russia, forest advanced to or near the current arctic coastline between 9000 and 7000 yr B.P. and retreated to its present position by between 4000 and 3000 yr B.P. Forest establishment and retreat was roughly synchronous across most of northern Russia. Treeline advance on the Kola Peninsula, however, appears to have occurred later than in other regions. During the period of maximum forest extension, the mean July temperatures along the northern coastline of Russia may have been 2.5° to 7.0°C warmer than modern. The development of forest and expansion of treeline likely reflects a number of complimentary environmental conditions, including heightened summer insolation, the demise of Eurasian ice sheets, reduced sea-ice cover, greater continentality with eustatically lower sea level, and extreme Arctic penetration of warm North Atlantic waters. The late Holocene retreat of Eurasian treeline coincides with declining summer insolation, cooling arctic waters, and neoglaciation.     

Characterization of Artificial,Small-Scale,Ionospheric Irregularities in the High-Latitude F Region Induced by High-Power,High-Frequency Radio Waves of Extraordinary Polarization

Geomagnetism and Aeronomy - The results of experimental studies of characteristics of artificial, small-scale, ionospheric irregularities in the high-latitude ionospheric F region caused by the...