The conformal invariance of unimodular gravity survives quantum corrections, even in the presence of conformal matter. Unimodular gravity can actually be understood as a certain truncation of the full Einstein-Hilbert theory, where in the Einstein frame the metric tensor has unit determinant. Our result is compatible with the idea that the corresponding restriction in the functional integral is consistent as well ; This work has been partially supported by the European Union FP7 ITN INVISIBLES (Marie Curie Actions, PITN- GA-2011- 289442) and (HPRN-CT-200- 00148) as well as by FPA2009-09017 (DGI del MCyT, Spain) and S2009ESP-1473 (CA Madrid). M. H. acknowledges a ''Campus de Excelencia'' grant from the Departamento de Física Teórica of the UAM. The authors acknowledge the support of the Spanish MINECO's ''Centro de Excelencia Severo Ochoa'' Programme under Grant No. SEV-2012-0249
The socio-economic condition in most COMESA countries is characterised by persistent high poverty levels and low food security. This is further compounded by the susceptibility of agriculture to climatic variability and other hazards as well as the vulnerability of impoverished and malnourished households to HIV/AIDS, market shocks and prolonged violent conflict. One of the biggest challenges governments in Africa face, with notably few exceptions, is the lack of sufficient financial and human resources to undertake the required action when disaster arises. This starts from the inability to address the underlying causes of disasters, including recurrent poverty that stifles household resilience (NEPAD, 2007). ; Non-PR ; IFPRI2; ReSAKSS ; DSGD
Action Track 2 works to catalyse a shift in consumer behaviour that will create and build demand for sustainably produced agriand ocean food products, strengthen shorter value chains, promote circular use of food resources, helping to reduce waste and improve nutrition, especially among the most vulnerable. This Action Track recognises that current food consumption patterns, often characterised by higher levels of food waste and a transition in diets towards higher energy, more resource-intensive foods, need to be transformed. Food systems in both developed and developing countries are changing rapidly. Increasingly characterized by a high degree of vertical integration, evolutions in food systems are being driven by new technologies that are changing production processes, distribution systems, marketing strategies, and the food products that people eat. These changes offer the opportunity for system-wide change in the way in which production interacts with the environment, giving greater attention to the ecosystem services offered by the food sector. However, developments in food systems also pose new challenges and controversies. Food system changes have responded to shifts in consumer preferences towards larger shares of more animal-sourced and processed foods in diets, raising concerns regarding the calorific and nutritional content of many food items. By increasing food availability, lowering prices and increasing quality standards, they have also induced greater food waste at the consumer end. In addition, the risk of fast transmission of food-borne disease, antimicrobial resistance and food-related health risks throughout the food chain has increased, and the ecological footprint of the global food system continues to grow in terms of energy, resource use, and impact on climate change. The negative consequences of food systems from a nutritional, environmental and livelihood perspective are increasingly being recognized by consumers in some regions. With growing consumer awareness, driven by concerns about the environmental and health impacts of investments and current supply chain technologies and practices, and by a desire among new generations of city dwellers to reconnect with their rural heritage and to use their own behaviour to drive positive change, opportunities exist to define and establish added-value products that are capable of internalising social or environmental delivery within their price. These forces can be used to fundamentally reshape food systems by stimulating coordinated government action in changing the regulatory environment that in turn incentivises improved private sector investment decisions. Achieving healthy diets from sustainable food systems is complex and requires a multi-pronged approach. Actions necessary include awareness-raising, behaviour change interventions in food environments, food education, strengthened urban-rural linkages, improved product design, investments in food system innovations, public private partnerships, public procurement, and separate collection enabling alternative uses of food waste can all contribute to this transition. Local and national policymakers and small and large scale private sector actors have a key role in both responding to and shaping the market opportunities created by changing consumer demands.
The problem of the comological constant appears in a new light in Unimodular Gravity. In particular, the zero momentum piece of the potential (that is, the constant piece independent of the matter fields) does not automatically produce a cosmological constant proportional to it. The aim of this paper is to give some details on a calculation showing that quantum corrections do not renormalize the classical value of this observable ; This work has been partially supported by the European Union FP7 ITN INVISIBLES (Marie Curie Actions, PITN- GA-2011- 289442) and (HPRN-CT-200-00148); COST action MP1405 (Quantum Structure of Spacetime), COST action MP1210 (The String Theory Universe) as well as by FPA2012-31880 (MICINN, Spain)), FPA2011-24568 (MICINN, Spain), and S2009ESP-1473 (CA Madrid). The authors acknowledge the support of the Spanish MINECO Centro de Excelencia Severo Ochoa Programme under grant SEV-2012-0249
Journal of High Energy Physics 2015.8 (2015): 078 reproduced by permission of Scuola Internazionale Superiore di Studi Avanzati (SISSA) ; The problem of the comological constant appears in a new light in Unimodular Gravity. In particular, the zero momentum piece of the potential (that is, the constant piece independent of the matter fields) does not automatically produce a cosmological constant proportional to it. The aim of this paper is to give some details on a calculation showing that quantum corrections do not renormalize the classical value of this observable ; This work has been partially supported by the European Union FP7 ITN INVISIBLES (Marie Curie Actions, PITN- GA-2011- 289442) and (HPRN-CT-200-00148); COST action MP1405 (Quantum Structure of Spacetime), COST action MP1210 (The String Theory Universe) as well as by FPA2012-31880 (MICINN, Spain), FPA2011-24568 (MICINN, Spain), and S2009ESP-1473 (CA Madrid). The authors acknowledge the support of the Spanish MINECO Centro de Excelencia Severo Ochoa Programme under grant SEV-2012-0249
Agriculture is considered to be "climate-smart" when it contributes to increasing food security, adaptation and mitigation in a sustainable way. This new concept now dominates current discussions in agricultural development because of its capacity to unite the agendas of the agriculture, development and climate change communities under one brand. In this opinion piece authored by scientists from a variety of international agricultural and climate research communities, we argue that the concept needs to be evaluated critically because the relationship between the three dimensions is poorly understood, such that practically any improved agricultural practice can be considered climate-smart. This lack of clarity may have contributed to the broad appeal of the concept. From the understanding that we must hold ourselves accountable to demonstrably better meet human needs in the short and long term within foreseeable local and planetary limits, we develop a conceptualization of climate-smart agriculture as agriculture that can be shown to bring us closer to safe operating spaces for agricultural and food systems across spatial and temporal scales. Improvements in the management of agricultural systems that bring us significantly closer to safe operating spaces will require transformations in governance and use of our natural resources, underpinned by enabling political, social and economic conditions beyond incremental changes. Establishing scientifically credible indicators and metrics of long-term safe operating spaces in the context of a changing climate and growing social-ecological challenges is critical to creating the societal demand and political will required to motivate deep transformations. Answering questions on how the needed transformational change can be achieved will require actively setting and testing hypotheses to refine and characterize our concepts of safer spaces for social-ecological systems across scales. This effort will demand prioritizing key areas of innovation, such as (1) improved adaptive management and governance of social-ecological systems; (2) development of meaningful and relevant integrated indicators of social-ecological systems; (3) gathering of quality integrated data, information, knowledge and analytical tools for improved models and scenarios in time frames and at scales relevant for decision-making; and (4) establishment of legitimate and empowered science policy dialogues on local to international scales to facilitate decision making informed by metrics and indicators of safe operating spaces.
100-year Global Warming Potentials (GWPs) are used almost universally to compare emissions of greenhouse gases in national inventories and reduction targets. GWPs have been criticised on several grounds, but little work has been done to determine global mitigation costs under alternative physics-based metrics . We used the integrated assessment model MESSAGE to compare emission pathways and abatement costs for fixed and time-dependent variants of the Global Temperature Change Potential (GTP) with those based on GWPs, for a policy goal of limiting the radiative forcing to a specified level in the year 2100. We find that fixed 100-year GTPs would increase global abatement costs (discounted and aggregated over the 21st century) under this policy goal by 5 20 % relative to 100-year GWPs, whereas time-varying GTPs would reduce costs by about 5 %. These cost differences are smaller than differences arising from alternative assumptions regarding agricultural mitigation potential and much smaller than those arising from alternative radiative forcing targets. Using the land-use model GLOBIOM, we show that alternative metrics affect food production differently in different world regions depending on regional characteristics of future land-use change to meet growing food demand. We conclude that under scenarios of complete participation, the choice of metric has a limited impact on global abatement costs but could be important for the political economy of regional and sectoral participation in collective mitigation efforts, in particular changing costs and gains over time for agriculture and energy-intensive sectors.
This work was undertaken as part of the CGIAR Research Program on Climate Change, Agriculture and Food Security (CCAFS), which is a strategic partnership of CGIAR and Future Earth. CCAFS is carried out with support from CGIAR Fund Donors and through bilateral funding agreements. This research has received funding from the European Union's FP7 Project FoodSecure (grant agreement no. 290693), the European Union's Horizon 2020 project CDLINKS (grant agreement no. 642147), and with technical support from the International Fund for Agricultural Development (IFAD). The views expressed in the document cannot be taken to reflect the official opinions of CGIAR, Future Earth, or donors. The contributions of PS, MH, and JFS contributes to the Belmont Forum/FACCE-JPI funded DEVIL project (NE/M021327/1) and to UGRASS (NE/M016900/1). FK acknowledges the support from IIASA's Tropical Futures Initiative (TFI) and the GCP's Managing Global Negative Emissions Technologies (MaGNET) program (www.cger.nies.go.jp/gcp/magnet.html). ; Peer reviewed ; Publisher PDF
Agriculture is considered to be "climate-smart" when it contributes to increasing food security, adaptation and mitigation in a sustainable way. This new concept now dominates current discussions in agricultural development because of its capacity to unite the agendas of the agriculture, development and climate change communities under one brand. In this opinion piece authored by scientists from a variety of international agricultural and climate research communities, we argue that the concept needs to be evaluated critically because the relationship between the three dimensions is poorly understood, such that practically any improved agricultural practice can be considered climate-smart. This lack of clarity may have contributed to the broad appeal of the concept. From the understanding that we must hold ourselves accountable to demonstrably better meet human needs in the short and long term within foreseeable local and planetary limits, we develop a conceptualization of climate-smart agriculture as agriculture that can be shown to bring us closer to safe operating spaces for agricultural and food systems across spatial and temporal scales. Improvements in the management of agricultural systems that bring us significantly closer to safe operating spaces will require transformations in governance and use of our natural resources, underpinned by enabling political, social and economic conditions beyond incremental changes. Establishing scientifically credible indicators and metrics of long-term safe operating spaces in the context of a changing climate and growing social-ecological challenges is critical to creating the societal demand and political will required to motivate deep transformations. Answering questions on how the needed transformational change can be achieved will require actively setting and testing hypotheses to refine and characterize our concepts of safer spaces for social-ecological systems across scales. This effort will demand prioritizing key areas of innovation, such as (1) improved adaptive management and governance of social-ecological systems; (2) development of meaningful and relevant integrated indicators of social-ecological systems; (3) gathering of quality integrated data, information, knowledge and analytical tools for improved models and scenarios in time frames and at scales relevant for decision-making; and (4) establishment of legitimate and empowered science policy dialogues on local to international scales to facilitate decision making informed by metrics and indicators of safe operating spaces.
Agriculture is considered to be "climate-smart" when it contributes to increasing food security, adaptation and mitigation in a sustainable way. This new concept now dominates current discussions in agricultural development because of its capacity to unite the agendas of the agriculture, development and climate change communities under one brand. In this opinion piece authored by scientists from a variety of international agricultural and climate research communities, we argue that the concept needs to be evaluated critically because the relationship between the three dimensions is poorly understood, such that practically any improved agricultural practice can be considered climate-smart. This lack of clarity may have contributed to the broad appeal of the concept. From the understanding that we must hold ourselves accountable to demonstrably better meet human needs in the short and long term within foreseeable local and planetary limits, we develop a conceptualization of climate-smart agriculture as agriculture that can be shown to bring us closer to safe operating spaces for agricultural and food systems across spatial and temporal scales. Improvements in the management of agricultural systems that bring us significantly closer to safe operating spaces will require transformations in governance and use of our natural resources, underpinned by enabling political, social and economic conditions beyond incremental changes. Establishing scientifically credible indicators and metrics of long-term safe operating spaces in the context of a changing climate and growing social-ecological challenges is critical to creating the societal demand and political will required to motivate deep transformations. Answering questions on how the needed transformational change can be achieved will require actively setting and testing hypotheses to refine and characterize our concepts of safer spaces for social-ecological systems across scales. This effort will demand prioritizing key areas of innovation, such as (1) improved adaptive management and governance of social-ecological systems; (2) development of meaningful and relevant integrated indicators of social-ecological systems; (3) gathering of quality integrated data, information, knowledge and analytical tools for improved models and scenarios in time frames and at scales relevant for decision-making; and (4) establishment of legitimate and empowered science policy dialogues on local to international scales to facilitate decision making informed by metrics and indicators of safe operating spaces.