A new validation scheme for the evaluation of multiparameter fields

On the basis of an extended cluster analysis algorithm, we present a new validation method for the evaluation of simulation experiments characterized by more than one parameter. This method allows the assessment of any parameter combination in space and time. As an example for the effectiveness of the algorithm, the results of two regional climate model runs and observational data have been tested and interpreted

Kulturen des Kopierschutzes II

Seit den 1990er Jahren war viel die Rede von Kopie und Simulation, Re­produzier­barkeit und Serialität. Doch dass schon das eigene Portemon­naie Dinge wie Geld und Personalpapiere enthält, die nicht kopiert wer­den sollen und von Normal­bürgern auch nicht kopiert werden können, wird oft vergessen. Wir leben (auch) in einer "Kultur des Kopierschutzes", in der verschiedene technische, diskursive und juristische Verfahren zu­sammenwirken, um die gesteigerte "technische Repro­duzierbarkeit", um Benjamins berühmten Ausdruck zu bemühen, im Zaum zu halten. Besonders deutlich wird das auch in den manchmal aufgeregten Diskus­sionen um den Status des Urheberrechts im Feld der digitalen Medien. Die beiden Hefte der Navigationen des Jahres 2010 sind das Ergebnis einer von Prof. Dr. Jens Schröter (Medienwissenschaft,Theorie und Praxis multi­medialer Systeme) geleiteten Projektgruppe im Masterstudiengang "Medienkul­tur". Die Studierenden haben im Rahmen des gesetzten Themas selbstständig Problemstellungen formuliert und diskutiert, dieErgebnisse dieser Arbeit sind in den beiden Heften publiziert - zusammen miteiner Reihe eingeladener Beiträge, die Aspekte abdecken, die in der Projektgruppe nicht bearbeitet werden konn­te

Reliability of regional climate model simulations of extremes and of long-term climate

We present two case studies that demonstrate how a common evaluation methodology can be used to assess the reliability of regional climate model simulations from different fields of research. In Case I, we focused on the agricultural yield loss risk for maize in Northeastern Brazil during a drought linked to an El-Niño event. In Case II, the present-day regional climatic conditions in Europe for a 10-year period are simulated. To comprehensively evaluate the model results for both kinds of investigations, we developed a general methodology. On its basis, we elaborated and implemented modules to assess the quality of model results using both advanced visualization techniques and statistical algorithms. Besides univariate approaches for individual near-surface parameters, we used multivariate statistics to investigate multiple near-surface parameters of interest together. For the latter case, we defined generalized quality measures to quantify the model's accuracy. Furthermore, we elaborated a diagnosis tool applicable for atmospheric variables to assess the model's accuracy in representing the physical processes above the surface under various aspects. By means of this evaluation approach, it could be demonstrated in Case Study I that the accuracy of the applied regional climate model resides at the same level as that we found for another regional model and a global model. Excessive precipitation during the rainy season in coastal regions could be identified as a major contribution leading to this result. In Case Study II, we also identified the accuracy of the investigated mean characteristics for near-surface temperature and precipitation to be comparable to another regional model. In this case, an artificial modulation of the used initial and boundary data during preprocessing could be identified as the major source of error in the simulation. Altogether, the achieved results for the presented investigations indicate the potential of our methodology to be applied as a common test bed to different fields of research in regional climate modeling

Variation of Natural Streamflow since 1470 in the Middle Yellow River, China

Nowadays, as the available water resources throughout the World are becoming depleted, in order to manage and plan water resource better, more and more attention is being paid into the fluctuating characteristics of water discharges. However, the preexisting research was mainly focused on the last half century. In this paper, the natural streamflow observed since 1470 at the Sanmenxia station in the middle Yellow River basin was collected, and the methods of variation coefficient, moving average, Mann-Kendall test and wavelet transform were applied to analyze the dynamic characteristics of the streamflow. The results showed that, (1) between 1470 and 2007, the natural streamflow changed 200–919 × 108 m3, and water discharge varied moderately; (2) in the middle Yellow River basin, it appears that the most severe and most persistent droughts during circa 1868–1990, the periods of 1470s–1490s, 1920s–1930s and 1990s–2000s also presented the condition of sustained low flows; (3) the natural streamflow series shows increasing and decreasing trends during the periods of 1470–1880 and 1881–2007, respectively, but both trends are not significant at >95% confidence; in addition, it is still found the streamflow series shows abrupt changes circa 1845, 1935 and 1960, respectively; (4) within a 250-year scale, there are circa 11, 26, 67 and 120-year periods for natural streamflow at the Sanmenxia station, and the periodicity of the 120-year one is the strongest. The dynamic characteristics of natural streamflow is the comprehensive result by many influencing factors, such as precipitation, temperature, El Niño-Southern Oscillation, sunspots, human activity, etc

Projections of global warming-induced impacts on winter storm losses in the German private household sector

We present projections of winter storm-induced insured losses in the German residential building sector for the 21st century. With this aim, two structurally most independent downscaling methods and one hybrid downscaling method are applied to a 3-member ensemble of ECHAM5/MPI-OM1 A1B scenario simulations. One method uses dynamical downscaling of intense winter storm events in the global model, and a transfer function to relate regional wind speeds to losses. The second method is based on a reshuffling of present day weather situations and sequences taking into account the change of their frequencies according to the linear temperature trends of the global runs. The third method uses statistical-dynamical downscaling, considering frequency changes of the occurrence of storm-prone weather patterns, and translation into loss by using empirical statistical distributions. The A1B scenario ensemble was downscaled by all three methods until 2070, and by the (statistical-) dynamical methods until 2100. Furthermore, all methods assume a constant statistical relationship between meteorology and insured losses and no developments other than climate change, such as in constructions or claims management. The study utilizes data provided by the German Insurance Association encompassing 24 years and with district-scale resolution. Compared to 1971–2000, the downscaling methods indicate an increase of 10-year return values (i.e. loss ratios per return period) of 6–35 % for 2011–2040, of 20–30 % for 2041–2070, and of 40–55 % for 2071–2100, respectively. Convolving various sources of uncertainty in one confidence statement (data-, loss model-, storm realization-, and Pareto fit-uncertainty), the return-level confidence interval for a return period of 15 years expands by more than a factor of two. Finally, we suggest how practitioners can deal with alternative scenarios or possible natural excursions of observed losses

Complex networks for climate model evaluation with application to statistical versus dynamical modeling of South American climate

Acknowledgments: This paper was developed within the scope of the IRTG 1740/TRP 2011/50151-0, funded by the DFG/FAPESP. Furthermore, this work has been financially supported by the Leibniz Society (project ECONS), and the Stordalen Foundation (JFD). For certain calculations, the software packages pyunicorn (Donges et al. 2013a) and igraph (Csa´rdi and Nepusz 2006) were used. The authors would like to thank Manoel F. Cardoso, Niklas Boers, and the reviewers for helpful comments on the manuscript. Open Access: This article is distributed under the terms of the Creative Commons Attribution License which permits any use, distribution, and reproduction in any medium, provided the original author(s) and the source are credited.Peer reviewedPostprin

Changes in the variability and periodicity of precipitation in Scotland

This paper analyses the temporal and spatial changes in the amount and variability of rainfall in Scotland. The sequential Mann–Kendall test reveals that total annual precipitation has increased across Scotland since the 1970s with increasing trends in variability beginning between the mid-1960s and the mid-1970s. Whilst temporally consistent increasing trends in precipitation totals prevail in the West, many weather stations in the East have experienced subsequent trend turning points in the following two decades, explaining the larger magnitude of the trends in western Scotland in recent decades. Trend analyses on six measures of rainfall variability indicate an increase in rainfall variability during the period 1961–2000, as measured by the intra-annual variance, the winter to summer precipitation ratio and the annual cumulative sum range, with decreasing trends observed in the number of dry days. Periodicities associated with the North Atlantic Oscillation and the Atlantic Multidecadal Oscillation could explain the observed temporal variability of rainfall

Anatomy in the Third Reich: An outline, part 1. National Socialist politics, anatomical institutions, and anatomists

Although it is known that anatomists working in Germany during the Third Reich have used bodies of victims of the National Socialist (NS) regime for dissection and research, a comprehensive history of the anatomy in the Third Reich has not yet been written. Recent studies of the history of German anatomy departments during this time period provide material for a first outline of the subject matter. A historical review can help with the formulation of ethical foundations in modern anatomy. From the outset, the NS regime sought to reorganize German universities according to NS leadership principles and political goals. Many German academics, especially physicians and among them anatomists, followed these intentions with a voluntary “self-alignment” that encompassed their professional actions as well as their ethics. Currently, political information is available for 111 of 178 anatomists. Thirty-eight of the anatomists were dismissed for racial or political reasons, among them 10 chairmen of anatomy, whereas 35 of the anatomists were politically active members of one of the NS organizations. Over 70% of the chairmen of anatomical departments in the time period from 1941 to 1944 were members of NS organizations. Anatomists, as so many other physicians and academics, belonged both, to the group of victims of the regime, i.e., those being dismissed from their positions for racial and political reasons, and to the group of supporters and sometimes active perpetrators of NS policies. Clin. Anat. 22:883–893, 2009. © 2009 Wiley-Liss, Inc.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/64328/1/20872_ftp.pd