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This article reviews some of the major lines of recent scientific progress relevant to the choice of global climate policy targets, focusing on changes in understanding since publication of the Intergovernmental Panel on Climate Change Fourth Assessment Report (IPCC AR4). Developments are highlighted in the following major climate system components: ice sheets; sea ice; the Atlantic Meridional Overturning Circulation; tropical forests; and accelerated carbon release from permafrost and ocean hydrates. The most significant developments in each component are identified by synthesizing input from multiple experts from each field. Overall, while large uncertainties remain in all fields, some substantial progress in understanding is revealed.

This paper reports how endogenous economic growth and technological change have been introduced into a global econometric model. It explains how further technological change might be induced by mitigation policies so as to reduce greenhouse gas emissions and stabilize atmospheric concentrations. These are the first results of a structural econometric approach to modeling the global economy using the model E3MG (energy-environment-economy model of the globe), which in turn constitutes one component in the Community Integrated Assessment System (CIAS) of the UK Tyndall Centre. The model is simplified to provide a post-Keynesian view of the long-run, with an indicator of technological progress affecting each region’s exports and energy use. When technological progress is endogenous in this way, long-run growth in global GDP is partly explained by the model. Average permit prices and tax rates about $430/tC (1995) prices after 2050 are sufficient to stabilize atmospheric concentrations at 450ppm CO2 after 2100. They also lead to higher economic growth.

Abstract One-step assembled CdSe/CdS (core/shell) quantum dots (QDs) were deposited onto ZnO nanowires (NWs) and characterized for their structure, morphology and optical analyses. As deposited ZnO NWs array were wurtzite in structure. During a single hydrothermal cycle a layer of ∼4 nm CdSe/CdS QDs was formed onto ZnO NWs and overgrowth evidenced with an additional 2–5 layers due to which, (a) absorbance density, and (b) Raman Shift of 1LO mode (from 286 cm −1 to 296 cm −1 ) increased and (c) the photoluminescence intensity of the near band-edge emission peak at ∼379 nm decreased. Due to more accumulation of CdSe/CdS, photoelectrochemical cells of ZnO-based photoelectrodes designed for 1–4 cycles of CdSe/CdS onto indium-tin-oxide substrate demonstrated increasing power conversion efficiency trend from 0.18% to 1.29% whereas, for 5th cycle power conversion efficiency, due to an increased series resistance, decreased to 1.12% on account of an accumulation of several QDs.

Abstract In this paper, multi-regional input–output analysis (MRIO) and ecological network analysis (ENA) are combined to assess carbon flows within China and identify key regions and sectors in the context of spatial heterogeneity for effective carbon mitigation. An interregional carbon network model is established by articulating the directions and magnitudes of carbon flows based on MRIO. ENA is then used to unveil indirect carbon flows and mutual relationships among regions. The results show that the northwest is the largest controller for most regions in China. Most carbon emissions in the rest of China are induced by the east’s final demand and substantial consumption. In addition, at sectoral level, the control and dependence abilities vary by region in China. This study provides an integrated framework to investigate interregional carbon emission structure, identify efficient pathways for coordinated emission mitigation, and reduce global carbon inequality across regions.

AbstractRecently, there have been several studies using open top chambers (OTCs) or cloches to examine the response of Arctic plant communities to artificially elevated temperatures. Few, however, have investigated multitrophic systems, or the effects of both temperature and vertebrate grazing treatments on invertebrates. This study investigated trophic interactions between an herbivorous insect (Sitobion calvulum, Aphididae), a woody perennial host plant (Salix polaris) and a selective vertebrate grazer (barnacle geese,Branta leucopsis). In a factorial experiment, the responses of the insect and its host to elevated temperatures using open top chambers (OTCs) and to three levels of goose grazing pressure were assessed over two summer growing seasons (2004 and 2005).OTCs significantly enhanced the leaf phenology ofSalixin both years and there was a significantOTCby goose presence interaction in 2004.Salixleaf number was unaffected by treatments in both years, butOTCs increased leaf size and mass in 2005.Salixreproduction and the phenology of flowers were unaffected by both treatments. Aphid densities were increased byOTCs but unaffected by goose presence in both years. While goose presence had little effect on aphid density or host plant phenology in this system, theOTCeffects provide interesting insights into the possibility of phenological synchrony disruption. The advanced phenology ofSalixeffectively lengthens the growing season for the plant, but despite a close association with leaf maturity, the population dynamics of the aphid appeared to lack a similar phenological response, except for the increased population observed.

The effects of the coupling between the morphological stability of a planar, horizontal crystal-melt interface of a growing crystal and solutal convection in the melt are explored using linear perturbation theory. The results are compared with the Mullins-Sekerka criterion (J. Appl. Phys. 35 (1964) 444) for morphological stability which neglects the effects of convection and with the recent numerical study by Coriell et al. (J. Crystal Growth 49 (1980) 13). It is found that the deformation of the interface due to the onset of solutal convection occurs above a critical value of the solutal Rayleigh number but that, below this critical value, the Mullins-Sekerka criterion for interface breakdown is not significantly altered by the inclusion of the fluid dynamics. An exception to this is the case where the temperature gradient in the melt is extremely small, when some small stabilisation of the interface against breakdown is predicted. Overstable modes of breakdown have been investigated and the form of the bifurcation studied. It is concluded that, under commonly encountered conditions of growth, the stationary instability is the first to occur.

Despite the fact that we currently witness an increasing interest in the study of the role of agency in policy dynamics, it remains in many respects a puzzle how policy change can be explained, let alone directed. This paper focusses intently on the concept, incidence, and strategic behaviour of policy entrepreneurs. By elucidating their strategic modus operandi, we aim to contribute to a better understanding of the strategies that individual change agents employ in their efforts to effect policy change, as well as to examine their contextual effectiveness. In addition to new data on the incidence and profile of policy entrepreneurs and the (contextual) conditions relating to the selection of strategies, this paper presents a novel typology of entrepreneurial strategies, linking these to circumstances under which they can be effective. Our paper concludes with a discussion on how our findings relate to the main theories of policy change, and what they mean for the larger democratic questions about accountability and legitimacy.

According to predicted changes in climate, waterlogging events may occur more frequently in the future during autumn and winter at high latitudes of the Northern Hemisphere. If excess soil water coincides with the process of cold acclimation for plants, winter survival may potentially be affected. The effects of waterlogging during cold acclimation on stomatal aperture, relative water content, photochemical activity of photosystem II, freezing tolerance and plant regrowth after freezing were compared for two prehardened overwintering forage grasses, Lolium perenne and Festuca pratensis. The experiment was performed to test the hypothesis that changes in photochemical activity initiated by waterlogging-triggered modifications in the stomatal aperture contribute to changes in freezing tolerance. Principal component analysis showed that waterlogging activated different adaptive strategies in the two species studied. The increased freezing tolerance of F. pratensis was associated with increased photochemical activity connected with stomatal opening, whereas freezing tolerance of L. perenne was associated with a decrease in stomatal aperture. In conclusion, waterlogging-triggered stomatal behavior contributed to the efficiency of the cold acclimation process in L. perenne and F. pratensis.