37 research outputs found

    Ground validation of oceanic snowfall detection in satellite climatologies during LOFZY

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    A thorough knowledge of global ocean precipitation is an indispensable prerequisite for the understanding of the water cycle in the global climate system. However, reliable detection of precipitation over the global oceans, especially of solid precipitation, remains a challenging task. This is true for both, passive microwave remote sensing and reanalysis based model estimates. The optical disdrometer ODM 470 is a ground validation instrument capable of measuring rain and snowfall on ships even under high wind speeds. It was used for the first time over the Nordic Seas during the LOFZY 2005 campaign. A dichotomous verification of precipitation occurrence resulted in a perfect correspondence between the disdrometer, a precipitation detector and a shipboard observer's log. The disdrometer data is further point-to-area collocated against precipitation from the satellite based Hamburg Ocean Atmosphere Parameters and fluxes from Satellite data (HOAPS) climatology. HOAPS precipitation turns out to be overall consistent with the disdrometer data resulting in a detection accuracy of 0.96. The collocated data comprises light precipitation events below 1 mm h–1. Therefore two LOFZY case studies with high precipitation rates are presented that indicate plausible HOAPS satellite precipitation rates. Overall, this encourages longer term measurements of ship-to-satellite collocated precipitation in the near future

    Validation of HOAPS Rain Retrievals against OceanRAIN In-Situ Measurements over the Atlantic Ocean

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    The satellite-derived HOAPS (Hamburg Ocean Atmosphere Parameters and Fluxes from Satellite Data) precipitation estimates have been validated against in-situ precipitation measurements from optical disdrometers, available from OceanRAIN (Ocean Rainfall And Ice-phase precipitation measurement Network) over the open-ocean by applying a statistical analysis for binary estimates. In addition to using directly collocated pairs of data, collocated data were merged within a certain temporal and spatial threshold into single events, according to the observation times. Although binary statistics do not show perfect agreement, simulations of areal estimates from the observations themselves indicate a reasonable performance of HOAPS to detect rain. However, there are deficits at low and mid-latitudes. Weaknesses also occur when analyzing the mean precipitation rates; HOAPS underperforms in the area of the intertropical convergence zone, where OceanRAIN observations show the highest mean precipitation rates. Histograms indicate that this is due to an underestimation of the frequency of moderate to high precipitation rates by HOAPS, which cannot be explained by areal averaging

    Recruiting and engaging adolescents in creating overweight and obesity prevention policies: The CO‐CREATE project

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    Special Issue: The CO‐CREATE Project: Co‐creating policy with youthThe CO-CREATE project aims to collaborate with adolescents across Europe in developing policy ideas that contribute to overweight and obesity prevention. In this paper, we present the theoretical basis and methodological approach to recruitment and engagement in the project. The principles of youth-led participatory action research were employed to design Youth Alliances in which adolescents and adults could collaborate. These Alliances should serve to promote and support adolescent participation and to develop policy ideas that would contribute to obesity prevention. Alliance members were recruited in two local geographical areas per country with a focus on reaching out to underrepresented youth. We started with fieldwork to assess locally relevant forms of inclusion and exclusion. The methodology entailed a handbook combining existing tools which could be used flexibly, a collaborative organization, and budgets for the alliances. Engagement started in local organizations, that is, schools and scouts, and with peers. Health- and overweight-related challenges were addressed in their immediate surroundings and supported the inclusion of experiential knowledge. Adolescents were then supported to address the wider obesogenic system when designing policy ideas. The CO-CREATE Alliances provide a concrete example of how to engage youth in public health, in a manner that strives to be participatory, transformative, and inquiry based.The “Confronting obesity: Co-creating policy with youth” (CO-CREATE) project has received funding from the European Union's Horizon 2020 research and innovation program under Grant 774210 (https://cordis.europa.eu/project/id/774210).info:eu-repo/semantics/publishedVersio

    Photopolymerizable nanocomposite photonic materials and their holographic applications in light and neutron optics

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    We present an overview of recent investigations of photopolymerizable nanocomposite photonic materials in which, thanks to their high degree of material selectivity, recorded volume gratings possess high refractive index modulation amplitude and high mechanical/thermal stability at the same time, providing versatile applications in light and neutron optics. We discuss the mechanism of grating formation in holographically exposed nanocomposite materials, based on a model of the photopolymerization-driven mutual diffusion of monomer and nanoparticles. Experimental inspection of the recorded gratings morphology by various physicochemical and optical methods is described. We then outline the holographic recording properties of volume gratings recorded in photopolymerizable nanocomposite materials consisting of inorganic/organic nanoparticles and monomers having various photopolymerization mechanisms. Finally, we show two examples of our holographic applications, holographic digital data storage and slow-neutron beam control.(VLID)286369

    Encouraging greater empowerment for adolescents in consent procedures in social science research and policy projects

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    The CO-CREATE project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No. 774210.The United Nations Convention on the Rights of the Child emphasizes the importance of allowing children and adolescents to influence decisions that are important to them following their age and maturity. This paper explores the principles, practices, and implications around using parental versus child/adolescent consent when participating in social science research and policy development. Experiences from two studies are presented: The Confronting Obesity: Co-creating policy with youth (CO-CREATE) and the Health Behaviour in School-aged Children (HBSC) study, a World Health Organization (WHO) Collaborative Cross-National study. Although parental consent may be an important gatekeeper for protecting children and adolescents from potentially harmful research participation, it may also be considered an obstacle to the empowerment of children and adolescents in case they want to share their views and experiences directly. This paper argues that evaluation of possible harm should be left to ethics committees and that, if no harm related to the research participation processes is identified and the project has a clear perspective on collaborating with the target group, adolescents from the age of 12 years should be granted the legal capacity to give consent to participate in the research project. Collaboration with adolescents in the development of the research project is encouraged.Publisher PDFPeer reviewe

    Validation practices for satellite based earth observation data across communities

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    Assessing the inherent uncertainties in satellite data products is a challenging task. Different technical approaches have been developed in the Earth Observation (EO) communities to address the validation problem which results in a large variety of methods as well as terminology. This paper reviews state-of-the-art methods of satellite validation and documents their similarities and differences. First the overall validation objectives and terminologies are specified, followed by a generic mathematical formulation of the validation problem. Metrics currently used as well as more advanced EO validation approaches are introduced thereafter. An outlook on the applicability and requirements of current EO validation approaches and targets is given

    World ocean review: Mit den Meeren leben 5. Die Küsten - ein wertvoller Lebensraum unter Druck

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    Die fünfte Ausgabe des „World Ocean Review“ (WOR) beschäftigt sich mit dem Lebensraum Küste und den vielfältigen Erwartungen, die an diesen Lebensraum gestellt werden. Der WOR 5 gibt einen Einblik in die über Jahrmillionen zurückreichende Geschichte, erläutert die Theorie der Kontinentalveschiebung und erörtert wie sich das Gesicht der Küsten verändert hat. Er zeigt auf, wie die vielfältigen Ökosystemleistungen der Küsten immer mehr unter Druck geraten und stellt Maßnahmen vor, die in Zukunft notwendig sein werden, um den Bedrohungen durch Klimawandel und Naturkatastrophen Herr zu werden

    World Ocean Review 2015 : living with the oceans 5. Coasts - a vital habitat under pressure

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    The fifth World Ocean Review (WOR) explores the coastal habitat and the diverse expectations upon this habitat. It provides a glimpse into millions of years of history, elucidates the theory of continental drift and discusses the many ways in which coasts have changed. It also illustrates how the diverse ecosystem services rendered by the coasts are being subjected to increasing pressure, and profiles measures that will be necessary in the future to respond effectively to the threats from both climate change and natural disasters
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