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To satisfy national sustainability targets in Germany, both bioenergy and organic farming claim a growing area of farmland. Analyses with a land use model and ac-companying expert interviews show, how the competition for land is growing in certain regions. A restricted area potential for energy crops – even with an ever intensifying farming opposes targets for an increasing share of land for organic agriculture and nature conservation. Thus there is a need for policy action, to discuss and solve this goal conflict. An ongoing study currently develops strategies for two selected German regions for a more ecologically compatible bioenergy production.

Organic farming has expanded rapidly in Europe during the last decade. In view of the agricultural policy trends, the current socio-political climate and a continuously growing demand for organic products, a further expansion of organic farming seems likely. In view of these prospects, the objective of this study is to provide a quantitative assessment of the impacts of a significant expansion of organic farming in the European Union on agricultural production, markets and the environment. Using and extending the EU-wide agricultural sector model CAPRI, different policy scenarios for a conversion of organic farming to 20 % of the agricultural area in the EU are analysed. The results indicate that such an expansion has a significant effect on several policy-relevant indicators, but this impact is less than often projected on the basis on farm level comparative calculations. This is due to several different intra- and inter-sectoral feedback loops (e.g. market equilibriums, quotas) which can only be captured using a sectoral approach. The model results point to the significant influence the policy instruments, and thus the regional distribution of organic farming and the distribution of converting farm types, have on the extent of potential impacts of a more widespread conversion. This highlights the scope for policy making to pursue policy objectives more efficiently by designing the support programs accordingly.

Forest biomass plays a crucial role in the quantification of the terrestrial carbon budget. Today, forest biomass is poorly quantified across most parts of the Earth surface due to the great difficulties in measuring biomass on the ground and consistently aggregating measurements across scales. SAR satellites can provide the required information globally and frequent in order to quantify current biomass state and the changes. Tandem-L is a German mission proposal for an innovative interferometric L-band radar mission that enables the systematic monitoring of dynamic Earth processes using advanced techniques and technologies. The mission is science driven aiming to provide a unique data set for climate and environmental research, geodynamics, hydrology and oceanography. Important application examples are global forest height and structure and the derivation of forest biomass. The Tandem-L mission concept consists of two cooperating satellites flying in close formation. The 3 D structure mode provides a unique data source to observe and quantify changes in forest biomass. This paper provides an overview of the potential of using multi-parametric SAR for forest structure estimation with the derivation of forest biomass and suggests a mission for a global acquisition.

In 2011 the German Advisory Council for Global Change (WBGU) published a remarkable policy document entitled ‘World in Transition: A Social Contract for Sustainability’ in which the authors proclaim the need for a great social transformation at the global scale in order to address climate change. This article builds on and critically discusses the central messages of the report that emphasizes the necessity to pro-actively shape the change of our values and worldviews that underpin our lifestyles and consumption patterns. By arguing for a transdisciplinary approach to implement this challenging vision the report identifies urbanization as a significant dimension in these processes thus shifting away from the dominant focus on socio-technical solutions. This puts the field of urban planning and development and related disciplines at the centre of the climate change adaptation and mitigation debate raising profound questions as to how these professionals, academics and practitioners could respond to the ideas brought forward in the report. The author considers this an opportunity for hitherto largely neglected integral approaches to gain more importance in mainstream urban planning practice and theory. The concluding part sketches out an initial research programme based on the previous discussion in order to illustrate at a more concrete level the implications of an integrative, transdisciplinary framework for planning.

Due to the increasing number of people living and/or working in dense urban environments, the importance of city planning in consideration of human health and comfort has been continuously growing. Health and comfort factors such as thermal comfort, air quality, ventilation and UV exposure, must be considered in a future-oriented development of urban regions. For decision support, urban climate models (UCM) are applied to model the effects of existing and planned building distributions, facade and city greening, etc., based on the above mentioned factors. A highly-efficient microscale UCM, PALM-4U, has been developed allowing simulations of large cities with grid-resolved buildings and vegetation canopy, which consider a large variety of processes important for urban environments. PALM-4U is part of the PALM model system (http://palm-model.org), which is based on the large-eddy simulation code PALM. While there exist numerous UCMs that have been used for over two decades and which are well established in the scientific community, they are difficult to adapt to state-of-the-art parallel computer systems and thus often have limitations in either performance and/or possible number of grid points. PALM-4U is able to compute entire city environments like Berlin (about 1 700 km²) at building-resolving grid spacing (here 10 m) on massively parallel computers, where limitations are mainly imposed by the available computational resources. It offers several features required in urban environments, such as an energy balance solver for urban and natural surfaces, radiative transfer in the urban canopy layer, chemical reactions, biometeorological analysis products, and self-nesting to allow high resolution (e.g. 1 m) in regions of special interest. In this presentation we will focus on an overview of PALM-4U's current and planned capabilities for application in urban environments. Besides, we will demonstrate PALM-4U's performance and features based on microscale building-resolving large-eddy simulation of entire Berlin (Germany, 1700 km²) at a grid spacing of 10 m, with a nested domain of size of 1 km² at a grid spacing of 1 m. The simulation spans a simulated period of a full diurnal cycle during a selected heat wave period and is characterized by low geostrophic winds and a strong solar forcing during daytime. General features of the simulation will be visualized. This presentation is intended to be the first in a series of presentations that all have a more specific focus on single features of PALM-4U and for which abstracts are submitted separately. In this overview talk we will thus focus on the more general features of the simulation.

The design of support structures of offshore wind turbines contains high number of design variables that influence load characteristics and structural responses. These variables are stochastic and cause many uncertainties. Some of them are examined in this study. It is investigated how scattering of site conditions and load parameters affect the structural response. It is exemplified in terms of stresses that contribute to the accumulated fatigue damage within a monopile substructure. Random sampling of combinations of site conditions and load parameters is performed in order to classify the effects of parameter scattering on the stress variability by means of Sobol’ indices. Analysis shows that the highest influence on stress outputs have the variations in the load parameters. The reason is the sensitivity of the structural dynamical response to the wave height increase and decrease of distance between the wave peak frequency and the structural eigenfrequencies. © 2017 ISOPE

The Biodynamic Research Institute in Järna developed at the farm Yttereneby a two phase biogas plant. The plant digests manure of dairy cattle and organic residues originating from the farm and the surrounding food processing units containing 17,7 - 19,6 % dry matter. A new technology for continuously filling and discharging the biogas reactor was developed and implemented. Digestion residues are separated into a solid fraction for composting and into a liquid fraction. The solid fraction is suitable for aerobic composting. Initial results show that anaerobic digestion and following aerobic composting of the solid fraction improves the nitrogen balance of the farm compared to mere aerobic composting. Composted biogas plant residues and effluent together contain 70,8 % of input Ntot and 93,3 % of input NH4, merely aerobic digested manure 51,3 % Ntot and 3,9 % NH4 only. Additionally anaerobic digestion improves the energy balance of the farm producing up to 269 l biogas kg-1 VS or 1,7 kWh heat kg-1 VS.

With its warm climate and large amounts of fertile lands South Africa has the potential to become a relevant player in the production of bioenergy. The increasing demand of the African continent for energy shows the need in renewable energy sources. On the other hand, large-scale land use for energy crops may induce food security risks keeping in mind the also growing population attending the increasing demand on edibles. With the vegetation model BETHY/DLR we estimated the potential for bioenergy production, considering food security and sustainability. For the year 2003 we estimate a biomass energy potential of 461 PJ which is about 9% of the energy supply of this year according to IEA.

Während in Asien und den USA der asiatische und insbesondere der chinesische Energiehunger bereits Mitte der 1990er Jahre auf der politischen Tagesordnung der Regierungen sowie vieler Diskussionen und Konferenzen war, blieb die Problematik in Europa fast unbeachtet. Im Glauben an die Allheilkräfte eines sich selbst regulierenden globalen Marktes von Angebot und Nachfrage galt die Analyse der asiatischen Energiemärkte und der chinesischen Energiepolitik als weitgehend entbehrlich. Darüber hinaus wurden mögliche Auswirkungen auf die Außen- und Sicherheitspolitik, das regionale Krisen- und Konfliktmanagement oder die globale Ordnungspolitik fast völlig ignoriert. So ist die Tatsache der rapide steigenden Energienachfrage aus China, Indien und anderen asiatischen Staaten sowie ihre globalen Auswirkungen in Deutschland bis Mitte 2004 kaum zur Kenntnis genommen worden. China aktuell, China aktuell - 1/2007