Combining atmospheric and snow radiative transfer models to assess the solar radiative effects of black carbon in the Arctic

The magnitude of solar radiative effects (cooling or warming) of black carbon (BC) particles embedded in the Arctic atmosphere and surface snow layer was explored on the basis of case studies. For this purpose, combined at- mospheric and snow radiative transfer simulations were per- formed for cloudless and cloudy conditions on the basis of BC mass concentrations measured in pristine early summer and more polluted early spring conditions. The area of inter- est is the remote sea-ice-covered Arctic Ocean in the vicin- ity of Spitsbergen, northern Greenland, and northern Alaska typically not affected by local pollution. To account for the radiative interactions between the black-carbon-containing snow surface layer and the atmosphere, an atmospheric and snow radiative transfer model were coupled iteratively. For pristine summer conditions (no atmospheric BC, minimum solar zenith angles of 55◦) and a representative BC particle mass concentration of 5 ng g−1 in the surface snow layer, a positive daily mean solar radiative forcing of +0.2Wm−2 was calculated for the surface radiative budget. A higher load of atmospheric BC representing early springtime conditions results in a slightly negative mean radiative forcing at the surface of about −0.05 W m−2, even when the low BC mass concentration measured in the pristine early summer condi- tions was embedded in the surface snow layer. The total net surface radiative forcing combining the effects of BC em- bedded in the atmosphere and in the snow layer strongly de- pends on the snow optical properties (snow specific surface area and snow density). For the conditions over the Arctic Ocean analyzed in the simulations, it was found that the at- mospheric heating rate by water vapor or clouds is 1 to 2 or-ders of magnitude larger than that by atmospheric BC. Sim- ilarly, the daily mean total heating rate (6 K d−1) within a snowpack due to absorption by the ice was more than 1 order of magnitude larger than that of atmospheric BC (0.2 K d−1). Also, it was shown that the cooling by atmospheric BC of the near-surface air and the warming effect by BC embedded in snow are reduced in the presence of clouds

Probleme und Unzulänglichkeiten bei der Anwendung von Normen oder Warum können Normen nicht perfekt sein?

Der Beitrag diskutiert die Problematik von EMV-Normen im Grundsatz: Trotz Definitionen und sorgfältiger Vorarbeit stellt sich in der Praxis heraus, dass auch eine beispielsweise im Konsensprinzip erarbeitete Norm nicht immer den Erwartungen aller Beteiligten entspricht oder auch teilweise Unzulänglichkeiten enthält, die ihre Anwendung erschweren. Die Entstehung von Normen wird betrachtet, auf die verschiedenen Einflussfaktoren auf Normen wird ausführlich eingegangen: regulatorische, normungstechnische, technische, kulturelle und finanzielle Einflussfaktoren

Seamless HPC Integration of Data-Intensive KNIME Workflows via UNICORE

Biological research is increasingly dependent on analyzing vast amounts of microscopy datasets. Technologies such as Fiji/ImageJ2 and KNIME support knowledge extraction from biological data by providing a large set of configurable algorithms and an intuitive pipeline creation and execution interface. The increasing complexity of required analysis pipelines and the growing amounts of data to be processed nurture the desire to run existing pipelines on HPC (High Performance Computing) systems. Here, we propose a solution to this challenge by presenting a new HPC integration method for KNIME (Konstanz Information Miner) using the UNICORE middleware (Uniform Interface to Computing Resources) and its automated data processing feature. We designed the integration to be efficient in processing large data workloads on the server side. On the client side it is seamless and lightweight to only minimally increase the complexity for the users. We describe our novel approach and evaluate it using an image processing pipeline that could previously not be executed on an HPC system. The evaluation includes a performance study of the induced overhead of the submission process and of the integrated image processing pipeline based on a large amount of data. This demonstrates how our solution enables scientists to transparently benefit from vast HPC resources without the need to migrate existing algorithms and pipelines

Heterogeneous Resource Federation with a Centralized Security Model for Information Extraction

With the continuous growth of data generated in various scientific and commercial endeavors and the rising need for interdisciplinary studies and applications in e-Science easy exchange of information and computation resources capable of processing large amounts of data to allow ad-hoc co-operation becomes ever more important. Unfortunately different communities often use incompatible resource management systems. In this work we try to alleviate the difficulties occurring on bridging the gap between different research eco-systems by federating resources and thus unifying resource access.To this end, our solution presented in this paper outlines a secure, simple, yet highly interoperable and flexible architecture using RESTful Web services and WebDAV. While, first and foremost in the Grid computing domain, there are already standards and solutions in place addressing related problems, our solution differs from those approaches by allowing to federate data storage systems that are not aware of being federated. Access to these is enabled by our federation layer using storage system specific connectors. Hence, our federation approach is intended as an abstraction layer on top of existing storage or middleware solutions, allowing for a more uniform access mechanism.Additionally, our solution also allows for submission and management of computational jobs on said data, thereby federating not only data but also computational resources. Once resource access is unified, information from different data formats can be semantically unified by information extraction methods. It is our belief that the work in this paper can complement existing Grid computing efforts by facilitating access to data storage system not inherently available via commonly used Grid computing standards

Interactive Information Extraction based on Distributed Data Management for D-Grid Projects

The current infrastructure proviced and maintained by the German Grid Initiative (D-Grid) primarily covers resource management and exchange at the data level supporting mainly technical resources such as computational capacity, data transport networks, storage resources, and management software. The WisNetGrid project (www.wisnetgrid.org) aims to broaden the focus of resource sharing towards the actual content, such as research and production data, to enable interdisciplinary usage. To achieve this goal, resource sharing is supported on different abstraction layers. First, we create an information layer by providing a universal interface to access data on the grid independent of the underlying grid storage system. Second, at the knowledge layer, we offer interactive knowledge extraction and management tools that can also take advantage of a community’s grid resources. These tools enable the user to formulate the domain specific knowledge in different ways to ease the interaction with the knowledge extraction process and to provide input for automatic extraction workflow. Within this project, we work together with use groups from the humanities and from landscaping as disparate use cases to evaluate which advantages can be gained by using semi-automatic extraction tools to gather and manage knowledge content

Combining atmospheric and snow radiative transfer models to assess the solar radiative effects of black carbon in the Arctic

The magnitude of solar radiative effects (cooling or warming) of black carbon (BC) particles embedded in the Arctic atmosphere and surface snow layer was explored on the basis of case studies. For this purpose, combined atmospheric and snow radiative transfer simulations were performed for cloudless and cloudy conditions on the basis of BC mass concentrations measured in pristine early summer and more polluted early spring conditions. The area of interest is the remote sea-ice-covered Arctic Ocean in the vicinity of Spitsbergen, northern Greenland, and northern Alaska typically not affected by local pollution. To account for the radiative interactions between the black-carbon-containing snow surface layer and the atmosphere, an atmospheric and snow radiative transfer model were coupled iteratively. For pristine summer conditions (no atmospheric BC, minimum solar zenith angles of 55 ) and a representative BC particle mass concentration of 5 ng g-1 in the surface snow layer, a positive daily mean solar radiative forcing of +0.2 W m-2 was calculated for the surface radiative budget. A higher load of atmospheric BC representing early springtime conditions results in a slightly negative mean radiative forcing at the surface of about -0.05 W m-2, even when the low BC mass concentration measured in the pristine early summer conditions was embedded in the surface snow layer. The total net surface radiative forcing combining the effects of BC embedded in the atmosphere and in the snow layer strongly depends on the snow optical properties (snow specific surface area and snow density). For the conditions over the Arctic Ocean analyzed in the simulations, it was found that the atmospheric heating rate by water vapor or clouds is 1 to 2 orders of magnitude larger than that by atmospheric BC. Similarly, the daily mean total heating rate (6 K d-1) within a snowpack due to absorption by the ice was more than 1 order of magnitude larger than that of atmospheric BC (0.2 K d-1). Also, it was shown that the cooling by atmospheric BC of the near-surface air and the warming effect by BC embedded in snow are reduced in the presence of clouds. © 2020 Copernicus GmbH. All rights reserved

EMV : Umsetzung der technischen und gesetzlichen Anforderungen an Anlagen und Gebäude sowie CE-Kennzeichnung von Geräten

Dieses Handbuch vermittelt die notwendigen EMV-Maßnahmen - von der Planungsphase bis zur Fertigstellung und CE-Kennzeichnung, vom Gerät bis zur großflächigen ortsfesten Anlage. Der Schwerpunkt des Buches liegt in der Berücksichtigung technischer und gesetzlicher Anforderungen und deren wirtschaftlicher Umsetzung zur Sicherstellung der EMV. Es ist als praxisorientierte Hilfestellung in der täglichen Arbeit gedacht unter Berücksichtigung des aktuellen Standes der Normung. Einführend werden die Grundlagen der EMV behandelt. Es folgen EMV-Grundmaßnahmen wie Massung, Erdung, Potentialausgleich, Filterung, Schirmung und Verkabelung. Mit der EMV-Planung wird eine Methodik zur Sicherstellung der EMV vorgestellt. Aufgezeigt werden besonders die EMV Maßnahmen in Gebäuden und Anlagen. Den Übergang zu Gesetzgebung und zur Normung für die CE-Kennzeichnung stellen die normativen Anforderungen an Geräte dar. Anwendungsbeispiele zu drehzahlveränderlichen Antrieben, zu Bahnfahrzeugen und zu anwendungsneutralen Kommunikationskabelanlagen vertiefen die EMV-Maßnahmen. Die Thematik "EMV & Funktionale Sicherheit" rundet das Werk ab