Kjeller, Norway
Kjeller, Norway

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Diapouli E.,L.E.S.S. | Eleftheriadis K.,L.E.S.S. | Karanasiou A.A.,L.E.S.S. | Vratolis S.,L.E.S.S. | And 3 more authors.
Aerosol and Air Quality Research | Year: 2011

The scope of this work was to characterize PM mass and number concentration at typical residential microenvironments in the centre of Athens and to examine the relative contribution of the indoor and outdoor sources. Three residential flats located in densely populated residential areas were studied, during a warm and cold period of 2002. PM 10, PM 2 and black carbon (BC) mass concentrations, as well as ultrafine and accumulation mode particle number size distributions were recorded indoors and outdoors simultaneously. Outdoor concentrations of all size fractions were significant, and indicative of urban sites affected by heavy traffic. Indoor levels were generally lower than the corresponding outdoor ones. Nevertheless, elevated indoor concentrations were recorded, caused by increased ambient air penetration in the indoor microenvironments and/or indoor particle generation. The mean 24-hr indoor PM 10 concentration at all residences was 35.0 ± 10.7 μg/m 3 during the warm period and 31.8 ± 7.8 μg/m 3 during the cold period. The corresponding PM 2 concentration was 30.1 ± 11.1 μg/m 3 and 27.2 ± 3.6 μg/m 3 during warm and cold periods, respectively. Regression analysis of indoor and outdoor concentration data revealed that indoor BC may be considered mainly of outdoor origin. A large fraction of the outdoor-generated PM 2 and ultrafine and accumulation mode particles also seems to penetrate indoors, causing elevated indoor levels. Regarding indoor particle generation, cooking was the strongest contributor in residential microenvironments. © Taiwan Association for Aerosol Research.

de Koeijer G.,Statoil | Talstad V.R.,Statoil | Nepstad S.,Statoil | Tonnessen D.,NILU | And 3 more authors.
International Journal of Greenhouse Gas Control | Year: 2013

A health risk analysis for the emissions to air from TCM's amine unit has been executed."The highest risk was assessed to be the exposure of the population to nitrosamines and nitramines."TCM's conclusion was that the risk was acceptable."The Norwegian Climate and Pollution Agency granted TCM a permit in November 2011. A health risk analysis for the emissions to air from the CO2 Technology Centre Mongstad (TCM) has been executed. TCM is the world's largest facility for testing and improving technologies for CO2 capture, and is located at the West coast of Norway. The risk analysis was an important fundament for the application for an emission permit for the amine based post-combustion CO2 capture unit. The highest risk was assessed to be the exposure of the population to uncertain concentrations of nitrosamines and nitramines in air and drinking water. Nitrosamines and nitramines are groups of possible degradation products formed from amines. The components within these two groups have variable degrees of carcinogenicity. Nitrosamines are formed from amines in the CO2 capture process and in the atmosphere, while nitramines are assumed to form only in the atmosphere. The risk was analyzed by comparing the sum of concentrations of nitrosamines and nitramines in air and fresh water with recently available guidelines. The concentrations were obtained by modelling atmospheric chemistry, dispersion, deposition by precipitation and degradation in fresh water with novel methods that were developed during the application process. Moreover, the nitrosamine and nitramine concentrations were measured in air and fresh water lakes prior to start-up as a baseline. TCM's conclusion was that the risk was acceptable. The Norwegian Climate and Pollution Agency granted TCM a permit in November 2011. © 2013 Elsevier Ltd.

Paris J.-D.,French National Center for Scientific Research | Ciais P.,French National Center for Scientific Research | Nedelec P.,CNRS Laboratory for Aerology | Stohl A.,NILU | And 5 more authors.
Bulletin of the American Meteorological Society | Year: 2010

Data from five Airborne Extensive Regional Observations in Siberia (YAK-AEROSIB) transcontinental campaigns, performed as a part of a joint French-Russian research program, provide new insights on the chemical composition of the Siberian air shed. The campaign, conducted on April, July, August, and September 2006, used an Antonov-30 Yak-Aerosib research aircraft equipped with new high-precision CO2, CO, and O3 instruments, and collected 50 in situ vertical profiles during the campaign. The results show that August mark the termination of the CO2 uptake period over Siberia, with flux tower data consistently indicating a switch in CO2 exchange by regional ecosystems from a sink to source. Higher surface biogenic volatile organic compounds (BVOC) emissions contribute to higher O3 production in summer. The September campaign showed a median CO concentration of 108 ppb and, 105 ppb in August 2007, and 102 ppb in July 2007.

News Article | March 4, 2016
Site: www.scientificcomputing.com

The new tool, called NEAT — Nested Environmental status Assessment Tool — is designed to support the assessment of marine areas by the environmental authorities of EU Member States, and also by the Regional Seas Conventions and for the Marine Strategy Framework Directive. It integrates a previously released tool that includes over 500 indicators used or being developed by European Member States and can be used for all types of environmental assessment. "NEAT allows us to assess the environmental status of European seas in an integrative way," says Dr. Borja of AZTI in Spain, an expert on marine biodiversity and coordinator of the European research project DEVOTES. "This is the result of collaborative effort of 23 partners, distributed across 14 countries, after four years of research in the Baltic, Atlantic, Mediterranean and Black Seas" says Borja. "Our research is important for improving the understanding of the effects of human activities on marine biodiversity, as well as variations due to climate change." "Marine health assessments are complex," says Borja, "but this tool makes the task much easier." According to Torsten Berg from MariLim in Germany, who is one of the authors of the software, "some of these tools can be difficult to use, so we worked hard to make a user-friendly interface." Using NEAT is simple, users first select the regional sea in which thee want to assess the status, and then choose the appropriate indicators, habitats and ecosystem components for a specific area within the regional sea. "NEAT determines the uncertainty of indicator values, so you can evaluate the confidence of your assessment. The more indicators and data you use, the better the assessment will be," highlights Jacob Carstensen from Aarhus University, an environmental statistician who worked on the development of the tool. But the very best of NEAT is its flexibility, "users can customize each step of the assessment, and the assessment better reflects the reality of the area," adds Jesper Andersen, from NIVA Denmark Water Research, who is one of the designers of the idea, "NEAT is so versatile that it can also be used for other types of environmental assessment, not just marine biodiversity." So, it could also be used by firms and consultancies that carry out all types of environmental assessment. NEAT and its guidelines are freely available from the DEVOTES Web site: www.devotes-project.eu/neat. In the coming months, NEAT will be enhanced with even more features and possibilities to perform a tailor-made biodiversity assessment. Updates will be released regularly. Project members are now disseminating the tool and organizing training workshops in member states and for regional seas conventions. "We have already demonstrated the tool to authorities in Portugal and Spain," says Alice Newton, from NILU in Norway and the University of Algarve in Portugal, "and it has been well-received by the Regional Seas Conventions." The DEVOTES project will be featured by the Euronews TV channel in June 2016 and will hold a conference in Brussels in October for key stakeholders and leading scientists. The theme of the conference is "Marine Biodiversity, the key to healthy and productive seas." Explore further: Clean seas by 2020: Scientists identify main environmental 'stressors' in the Mediterranean and Black Seas

Burton M.R.,Italian National Institute of Geophysics and Volcanology | Prata F.,NILU | Platt U.,University of Heidelberg
Journal of Volcanology and Geothermal Research | Year: 2015

Ground-based volcanic gas and ash imaging has the potential to revolutionise the way in which volcanoes are monitored and studied. The ability to track and quantify volcanic emissions in space and time with unprecedented fidelity opens the door to integration with geophysical measurements, allowing breakthroughs in our understanding of the physical processes driving volcanic activity. In May 2013 a European Science Foundation funded Plume Imaging workshop was conducted in Stromboli, Italy, with the objective of bringing the ground-based volcanic plume imaging community together in order to examine the state of the art, and move towards a 'best-practice' for volcanic ash and gas imaging techniques. A particular focus was the development of SO2 imaging systems, or SO2 cameras, with six teams deploying and testing various designs of ultraviolet and infrared-based imaging systems capable of imagining SO2. One conclusion of the workshop was that the term 'SO2 camera' should be applied to any SO2 imaging system, regardless of wavelength of radiation used.This Special Issue on Volcanic Plume Imaging is the direct result of the Stromboli workshop, and together the papers presented here represent the state of the art of ground-based volcano plume imaging science and technology. In this work, we examine in detail the volcanological applications of the SO2 camera, reviewing previous works and placing the new research contained in this Special Issue in context. The development of the SO2 camera, and future developments extending imaging to other volcanic gases, is one of the most exciting and novel research frontiers in volcanology today. © 2014.

Sodemann H.,NILU | Sodemann H.,ETH Zurich | Stohl A.,NILU
Monthly Weather Review | Year: 2013

During December 2006 many cyclones traveled across the North Atlantic, causing temperature and precipitation in Norway to be well above average. Large excursions of high vertically integrated water vapor, often referred to as atmospheric rivers, reached from the subtropics to high latitudes, inducing precipitation over western Scandinavia. The sources and transport of atmospheric water vapor in the North Atlantic storm track during that month are examined by means of a mesoscale model fitted with water vapor tracers. Decomposition of the modeled total water vapor field into numerical water vapor tracers tagged by evaporation latitude shows that when an atmospheric river was present, a higher fraction of water vapor from remote, southerly source regions caused more intense precipitation. The tracer transport analysis revealed that the atmospheric rivers were composed of a sequence of meridional excursions of water vapor, in close correspondence with the upper-level flow configuration. In cyclone cores, fast turnover of water vapor by evaporation and condensation were identified, leading to a rapid assimilation of water from the underlying ocean surface. In the regions of long-range transport,water vapor tracers fromthe southernmidlatitudes and subtropics dominated over local contributions. By advection of water vapor along their trailing cold fronts cyclones were reinforcing the atmospheric rivers. At the same time the warm conveyor belt circulation was feeding off the atmospheric rivers by large-scale ascent and precipitation. Pronounced atmospheric rivers could persist in the domain throughout more than one cyclone's life cycle. These findings emphasize the interrelation between midlatitude cyclones and atmospheric rivers but also their distinction from the warm conveyor belt airstream © 2013 American Meteorological Society.

Barre J.,U.S. National Center for Atmospheric Research | Edwards D.,U.S. National Center for Atmospheric Research | Worden H.,U.S. National Center for Atmospheric Research | Da Silva A.,NASA | Lahoz W.,NILU
Atmospheric Environment | Year: 2015

By the end of the current decade, there are plans to deploy several geostationary Earth orbit (GEO) satellite missions for atmospheric composition over North America, East Asia and Europe with additional missions proposed. Together, these present the possibility of a constellation of geostationary platforms to achieve continuous time-resolved high-density observations over continental domains for mapping pollutant sources and variability at diurnal and local scales. In this paper, we use a novel approach to sample a very high global resolution model (GEOS-5 at 7km horizontal resolution) to produce a dataset of synthetic carbon monoxide pollution observations representative of those potentially obtainable from a GEO satellite constellation with predicted measurement sensitivities based on current remote sensing capabilities. Part 1 of this study focuses on the production of simulated synthetic measurements for air quality OSSEs (Observing System Simulation Experiments). We simulate carbon monoxide nadir retrievals using a technique that provides realistic measurements with very low computational cost. We discuss the sampling methodology: the projection of footprints and areas of regard for geostationary geometries over each of the North America, East Asia and Europe regions; the regression method to simulate measurement sensitivity; and the measurement error simulation. A detailed analysis of the simulated observation sensitivity is performed, and limitations of the method are discussed. We also describe impacts from clouds, showing that the efficiency of an instrument making atmospheric composition measurements on a geostationary platform is dependent on the dominant weather regime over a given region and the pixel size resolution. These results demonstrate the viability of the "instrument simulator" step for an OSSE to assess the performance of a constellation of geostationary satellites for air quality measurements. We describe the OSSE results in a follow up paper (Part 2 of this study). © 2015 Elsevier Ltd.

Castell N.,NILU | Kobernus M.,NILU | Liu H.-Y.,NILU | Schneider P.,NILU | And 3 more authors.
Urban Climate | Year: 2015

The impact of mobile technologies on the Citizens' Observatory in the areas of air quality, environmental health and climate change, has the potential to significantly improve data coverage by the provision of near-real-time high-resolution data over urban areas. The Citi-Sense-MOB Citizens' Observatory will be part of an environmental health monitoring system and environmental health knowledge base, created from information provided by GNSS (Global Navigation Satellite Systems) signals such as GPS (Global Positioning System) and Citizens' Observatory data. The main objective of Citi-Sense-MOB is to support green growth and sustainable development in Oslo, Norway, by providing citizens and authorities with information on transport, CO2 emissions and air quality. This paper presents the approach used to develop the information value chain necessary to the success of Citi-Sense-MOB, from the sensor platform and architecture to the products and services supporting participatory governance through the Citizens' Observatory concept. © 2014 Elsevier B.V.

Lahoz W.A.,NILU | Lahoz W.A.,Meteo - France | De Lannoy G.J.M.,NASA
Surveys in Geophysics | Year: 2014

This paper reviews the conceptual problems limiting our current knowledge of the hydrological cycle over land. We start from the premise that to understand the hydrological cycle we need to make observations and develop dynamic models that encapsulate our understanding. Yet, neither the observations nor the models could give a complete picture of the hydrological cycle. Data assimilation combines observational and model information and adds value to both the model and the observations, yielding increasingly consistent and complete estimates of hydrological components. In this review paper we provide a historical perspective of conceptual problems and discuss state-of-the-art hydrological observing, modelling and data assimilation systems. © 2013 The Author(s).

Thomas H.E.,Michigan Technological University | Watson I.M.,Michigan Technological University | Watson I.M.,University of Bristol | Carn S.A.,Michigan Technological University | And 2 more authors.
Geomatics, Natural Hazards and Risk | Year: 2011

Volcanic degassing is a major contributor to the global sulphur dioxide (SO 2) budget, characterized by quiescent emissions in the lower troposphere with sporadic, spatially variable explosive eruptions into the upper troposphere and lower stratosphere (UTLS). The volcanic input of SO 2 to the atmosphere can be quantified using a suite of satellite-based instruments with a range of orbits and resolutions, resulting in differing estimates of SO 2 extent and concentration from eruptions. We compare near-coincident retrievals of SO 2 from the Moderate Resolution Imaging Spectroradiometer (MODIS), Atmospheric Infrared Radiation Sounder (AIRS) and OzoneMonitoring Instrument (OMI) at four eruptive settings. The OMI instrument is the most sensitive, with the ability to detect both low and high altitude clouds, but as an ultraviolet sensor, retrievals are limited to daytime, unlike the infrared sensors. AIRS retrievals are up to an order of magnitude less sensitive than OMI, restricted to water-free clouds in the upper troposphere. MODIS has the lowest sensitivity and is therefore constrained to the largest eruptions. Total tonnages from each sensor reflect these varying sensitivities along with potential calibration discrepancies. Results suggest that by using a number of instruments in synergy a more complete method of eruption detection is achieved. © 2011 Taylor & Francis.

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