244 research outputs found
Low-Carbon Land Transport: Policy Handbook, D. Bongardt, F. Creutzig, H. Hüging, K. Sakamoto, S. Bakker, S. Gota, S. Böhler-Baedecker. Routledge, Abingdon (2013). £49.00 (hardback), ISBN: 978-1-84971-377-1 [Book review]
No full textLow-Carbon Land Transport: Policy Handbook, D. Bongardt, F. Creutzig, H. Hüging, K. Sakamoto, S. Bakker, S. Gota, S. Böhler-Baedecker. Routledge, Abingdon (2013). £49.00 (hardback), ISBN: 978-1-84971-377-1 [Book review
Climate policies for road transport revisited (II): Closing the policy gap with cap-and-trade
No full textCurrent policies in the road transport sector fail to deliver consistent and efficient incentives for greenhouse gas abatement (see companion article by Creutzig et al., 2010a). Market-based instruments such as cap-and-trade systems close this policy gap and are complementary to traditional policies which are required where specific market failures arise. Even in presence of strong existing non-market policies, cap-and-trade delivers additional abatement and efficiency by incentivizing demand side abatement options. This paper analyzes generic design options and economic impacts of including the European road transport sector to the EU ETS. The point of regulation in a road transport cap-and-trade system should be upstream in the fuel chain to ensure effectiveness (cover all life-cycle emissions and avoid double-counting), efficiency (incentivize all abatement options) and low transaction costs. Based on year 2020 marginal abatement cost curves from different models and current EU climate policy objectives we show that in contrast to conventional wisdom road transport inclusion would not change the EU ETS allowance price. This puts concerns over industrial carbon leakage as a consequence of adding road transport to the EU ETS into perspective.Climate Policy, Road Transport, Cap-and-trade
Climate policies for road transport revisited (I): Evaluation of the current framework
No full textThe global rise of greenhouse gas (GHG) emissions and its potentially devastating consequences require a comprehensive regulatory framework for reducing emissions, including those from the transport sector. Alternative fuels and technologies have been promoted as means for reducing the carbon intensity of the transport sector. However, the overall transport policy framework in major world economies is geared towards the use of conventional fossil fuels. This paper evaluates the effectiveness and efficiency of current climate policies for road transport that (1) target fuel producers and/or car manufacturers, and (2) influence use of alternative fuels and technologies. With diversifying fuel supply chains, carbon intensity of fuels and energy efficiency of vehicles cannot be regulated by a single instrument. We demonstrate that vehicles are best regulated across all fuels in terms of energy per distance. We conclude that price-based policies and a cap on total emissions are essential for alleviating rebound effects and perverse incentives of fuel efficiency standards and low carbon fuel standards. In tandem with existing policy tools, cap and price signal policies incentivize all emissions reduction options. Design and effects of cap and trade in the transport sector are investigated in the companion article (Flachsland et al., 2010).Fuel efficiency standards, low carbon fuel standards, climate change
Timescale-invariant representation of acoustic communication signals by a bursting neuron
No full textAcoustic communication often involves complex sound motifs in which the relative durations of individual elements, but not their absolute durations, convey meaning. Decoding such signals requires an explicit or implicit calculation of the ratios between time intervals. Using grasshopper communication as a model, we demonstrate how this seemingly difficult computation can be solved in real time by a small set of auditory neurons. One of these cells, an ascending interneuron, generates bursts of action potentials in response to the rhythmic syllable-pause structure of grasshopper calls. Our data show that these bursts are preferentially triggered at syllable onset; the number of spikes within the burst is linearly correlated with the duration of the preceding pause. Integrating the number of spikes over a fixed time window therefore leads to a total spike count that reflects the characteristic syllable-to-pause ratio of the species while being invariant to playing back the call faster or slower. Such a timescale-invariant recognition is essential under natural conditions, because grasshoppers do not thermoregulate; the call of a sender sitting in the shade will be slower than that of a grasshopper in the sun. Our results show that timescale-invariant stimulus recognition can be implemented at the single-cell level without directly calculating the ratio between pulse and interpulse durations
A Comparative Analysis of the Equity Outcomes in Three Sugarcane–Ethanol Systems
No full textThis article identifies equity outcomes associated with three biofuel systems in Brazil, Ethiopia, and Guatemala. Acknowledging that winners and losers are socially and politically generated, the article identifies some of the factors behind the distribution of winners and losers along different stages of three sugarcane–ethanol supply chains. Analyzing the outcomes for equity within each case study reveals an uneven distribution that, we argue, is related to the procedure and structure of the given sugarcane–ethanol system, and the recognition of the impacts on different actors within those structures. Increasing equity in sugarcane–ethanol systems will require greater openness in decision-making processes, in order that multiple voices are taken into account in the promotion, production, and consumption of biofuels—particularly those of smaller and less powerful actors
The limited impact electro mobility will have on reaching climate change mitigation targets
No full textThe transport sector has been identified as a key barrier to decarbonisation based on the high costs of substituting energy-dense liquid fossil fuels. A potential solution is in the transition to electro-mobility, and more specifically to Electric Vehicles (Heidrich et al., 2017). Previous research has demonstrated that EVs offer the potential for large scale carbon reduction in the transport sector. The belief that EVs can deliver high carbon reductions requires better underpinning of detailed national or regional studies that are informed both by empirical and conceptual detail (Creutzig et al., 2015).It is generally believed that large reductions in road transport carbon emissions are urgently needed to meet global and national targets as specified in the Paris Agreement and the UK’s own carbon budget (Miotti et al., 2016). A shift in road transport from the Internal Combustion Engine (ICE) to Electric Vehicles (EVs) promises significant reductions in emitted CO2. However, the transition to a low carbon mode of transport will not be instantaneous and any policy or technological change implemented now will take years to have the desired effect. Within this paper we show how on-road emission factors of EVs and models of embedded CO2 in the vehicle production may be combined with statistics for vehicle uptake/replacement to forecast future transport emissions (Hill et al., 2019).We demonstrate that EVs, when compared to an efficient ICE, provides few benefits in terms of CO2 mitigation until 2030. However, between 2030 and 2050, predicted carbon savings under the different EV uptake and decarbonisation scenarios begin to diverge with large carbon savings seen for the accelerated EV uptake. This work shows that simply focussing on on-road emissions is insufficient to model the future CO2 impact of transport. Instead a full life-cycle calculation must be combined with an EV uptake model. Using this extended model, our scenarios show how the lack of difference between a Business as Usual and accelerated EV uptake scenario can be explained by the time-lag in cause and effect between policy changes and the desired change in the vehicle fleet.Our work reveals that current UK policy is unlikely to achieve the desired reduction in transport-based CO2 by 2030. If embedded CO2 is included as part of the transport emissions sector, then all possible UK EV scenarios will miss the reduction target for 2050. This result highlights that whilst EVs offer an important contribution to decarbonisation it is necessary to look at other transport mitigation strategies, such as modal shift to public transit, car sharing and demand management, to achieve both near-term and long-term mitigation targets.We conclude that whilst EVs will not provide a solution for near-term CO2 mitigation, it will be possible to achieve the short term carbon reduction goals through demand-side solutions, rather than simply focussing on the supply side solutions implied by electric vehicles. Whilst the majority of change in on-road CO2 emissions (for light duty passenger vehicles especially) has come from technological improvements, demand side solutions to either reduce travel demand or induce a modal shift hold promise, often also for quality of life. Demand side solutions of this nature can be implemented alongside the technological solutions and will provide a multiplier effect that will not be dependent on possible future technologies.ReferencesCREUTZIG, F., JOCHEM, P., EDELENBOSCH, O. Y., MATTAUCH, L., VAN VUUREN, D. P., MCCOLLUM, D. & MINX, J. 2015. Transport: A roadblock to climate change mitigation? Science, 350, 911-912.HEIDRICH, O., HILL, G. A., NEAIMEH, M., HUEBNER, Y., BLYTHE, P. T. & DAWSON, R. J. 2017. How do cities support electric vehicles and what difference does it make? Technological Forecasting and Social Change, 123, 17-23.HILL, G., HEIDRICH, O., CREUTZIG, F. & BLYTHE, P. 2019. The role of electric vehicles in near-term mitigation pathways and achieving the UK’s carbon budget. Applied Energy, 251, 113111.MIOTTI, M., SUPRAN, G. J., KIM, E. J. & TRANCIK, J. E. 2016. Personal Vehicles Evaluated against Climate Change Mitigation Targets. Environmental Science and Technology, 50, 10795-10804
Scoping Review: Behavioural Interventions to Reduce Household GHG Emissions
No full textSupporting references for Table 5.3 in the IPCC's Sixth Assessment Report, Working Group Three: Mitigation, Chapter 5. Creutzig, F., Roy, J., Devine-Wright , P., Diaz-José, J., Geels, F., Gruebler, A., Maïzi, N., Masanet, E., Mulugetta, Y., Chioma, D.O., Perkins, P.E., Sanches Pereira, A., Weber, E.U. (2022). Demand, services, and social aspects of mitigation In: Climate Change 2021: Mitigation of Climate Change. Contribution of Working Group III to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change [ (eds.)]. Cambridge University Press, Cambridge, UK and New York, NY, USA
Linear vs. nonlinear algorithms for linear problems
No full textAbstractWe compare linear and non–linear approximations for linear problems. Let X be a linear space and Y a normed space. Let S:X→Y and N:X→Rn be linear mappings and consider the worst–case setting over some balanced convex set F⊆X. We compare the minimal error errlin(S,N) achievable by linear algorithms processing N with the minimal error err(S,N) achievable by arbitrary algorithms using N. For bounded linear problems, P. Mathé showed that infNerrlin(S,N)⩽(1+n1/2)·infNerr(S,N),where the infimum is taken over all bounded linear mappings N:X→Rn. We generalize this result as follows: If the target space Y is complete, then for any linear N:X→Rn we have errlin(S,N,F)⩽(1+n1/2)err(S,N,F).This and some similar results can easily be derived from a general relation of this problem to extension properties of normed spaces, and the manifold and powerful results available for this problem. This allows a unified treatment of the above estimate together with the results of Smolyak and Packel, who showed that linear algorithms are optimal for some Y. The results are also partially extended to noisy information with uniformly bounded noise
Chronic myelomonocytic leukemia in childhood: A retrospective analysis of 110 cases
No full textChronic myelomonocytic leukemia (CMML) is a rare hematopoietic malignancy of childhood. To define the clinical and hematologic characteristics of the disease, we performed a retrospective analysis of 110 children given the diagnosis CMML irrespective of karyotype. Median age at diagnosis was 1.8 years. Neurofibromatosis type 1 was known in 14% and other clinical abnormalities in 7% of the children. At presentation, the medium white blood count was 35 x 109/L, with a median monocyte count of 7 x 109/L. Karyotypic abnormalities in bone marrow cells were noted in 36% of the patients, whereas 26% of the children had monosomy 7. Children with monosomy 7 did not differ from those with normal karyotype with respect to their clinical presentation. However, they did display some characteristic hematologic features. Of 110 children, 38 received an allogeneic bone marrow transplant (BMT). The probability of survival at 10 years was 0.39 (standard error [SE] = 0.10) for the BMT group and 0.06 (SE = 0.4) for the 72 patients of the non-BMT group. Platelet count, age, and hemoglobin F at diagnosis were the main predicting factors for the length of survival in the non-BMT group. There is a strong need for a broad agreement on nomenclature in children with myelodysplastic syndromes (MDS). We propose here to use the French-American- British classification for MDS in childhood
Predictive coding and the slowness principle: an information-theoretic approach.
No full textUnderstanding the guiding principles of sensory coding strategies is a main goal in computational neuroscience. Among others, the principles of predictive coding and slowness appear to capture aspects of sensory processing. Predictive coding postulates that sensory systems are adapted to the structure of their input signals such that information about future inputs is encoded. Slow feature analysis (SFA) is a method for extracting slowly varying components from quickly varying input signals, thereby learning temporally invariant features. Here, we use the information bottleneck method to state an information-theoretic objective function for temporally local predictive coding. We then show that the linear case of SFA can be interpreted as a variant of predictive coding that maximizes the mutual information between the current output of the system and the input signal in the next time step. This demonstrates that the slowness principle and predictive coding are intimately related
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