TY - CHAP A1 - Weber, Konradin A1 - Eliasson, Jonas A1 - Arnason, Gylfi A1 - Rögnvaldsson, Ólafur A1 - Thorsteinsson, Throstur A1 - Palsson, Thorgeir A1 - Böhlke, Christoph A1 - Fischer, Christian A1 - Smith, Paul A1 - Jones, Roderic L. A1 - Tirpitz, Lukas A1 - Platt, Ulrich T1 - Airborne Investigations and WRF - Model Calculations of the Bardarbunga-Holuhraun Eruption Plume T2 - Geophysical Research Abstracts: EGU General Assembly 2015 N2 - The eruption in Holuhraun is the largest producer of lava and gas in Iceland since 1783. The Volcanic Ash Research (VAR) group organized an airborne measurement campaign including 10 flights, where emissions of SO2 and ash concentrations were measured at the source and at the far plume. The highest SO2 concentration at the source was nearly up to 100 mg/m3. This is an extremely high value, compared to other airborne campaigns and a contamination considered to cause serious illness by the Icelandic Directorate of Health. Volcanic ash consisted of very fine particles, but the concentration was low when compared to other recent eruptions. Measurements of the far plume showed that scavenging is very active. The dispersion was successfully modeled with the Weather Research and Foreast (WRF-chem) model and analysis using the model showed that a large amount of the sulphur was precipitated in the Icelandic highlands. KW - Luftreinhaltung KW - Vulkanismus KW - Vulkanasche KW - Messtechnik KW - Atmosphärisches Aerosol KW - Schwefeldioxid Y1 - 2015 UR - https://web.archive.org/web/20240719170649/https://meetingorganizer.copernicus.org/EGU2015/EGU2015-10846-1.pdf N1 - Vortragsabstract VL - 17 PB - Copernicus CY - Göttingen ER - TY - JOUR A1 - Eliasson, Jonas A1 - Yoshitani, Junichi A1 - Weber, Konradin A1 - Yasuda, Nario A1 - Iguchi, Masato A1 - Vogel, Andreas T1 - Airborne Measurement in the Ash Plume from Mount Sakurajima: Analysis of Gravitational Effects on Dispersion and Fallout JF - International Journal of Atmospheric Sciences N2 - Volcanic ash concentrations in the plume from Sakurajima volcano in Japan are observed from airplanes equipped with optical particle counters and GPS tracking devices. The volcano emits several puffs a day. The puffs are also recorded by the Sakurajima Volcanological Observatory. High concentrations are observed in the puffs and fallout driven by vertical air current, called streak fallout. Puffs dispersion is analyzed by the classical diffusion-advection method and a new gravitational dispersion method. The fluid mechanic of the gravitational dispersion, streak fallout, and classical diffusion-advection theory is described in three separate appendices together with methods to find the time gravitational dispersion constant and the diffusion coefficient from satellite photos. The diffusion-advection equation may be used to scale volcanic eruptions so the same eruption plumes can be scaled to constant flux and wind conditions or two eruptions can be scaled to each other. The dispersion analyses show that dispersion of volcanic plumes does not follow either theories completely. It is most likely diffusion in the interface of the plume and the ambient air, together with gravitational flattening of the plumes core. This means larger boundary concentration gradients and smaller diffusion coefficients than state of the art methods can predict. KW - Luftreinhaltung KW - Vulkanismus KW - Vulkanasche KW - Messtechnik KW - Atmosphärisches Aerosol Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:hbz:due62-opus-50955 SN - 2314-4122 VL - 2014 PB - Wiley ER - TY - CHAP A1 - Weber, Konradin A1 - Fischer, Christian A1 - Vogel, Andreas A1 - Pohl, Tobias A1 - Böhlke, Christoph A1 - Lau, Hendrik A1 - Eliasson, Jonas A1 - Palsson, Thorgeir ED - Mladenov, Valeri ED - Tasho, Tashev ED - Hui, Wang ED - Ivan, Kralov ED - Sergey, Stankevich ED - Pelin, Yildiz ED - Jon, Burley T1 - First results of an airborne release of volcanic ash for testing of volcanic ash plume measurement instruments T2 - Recent Advances in Energy and Environmental Management KW - Luftreinhaltung KW - Vulkanasche KW - Messtechnik KW - Forschungsflugzeug Y1 - 2013 VL - Energy, Environmental and Structural Engineering Series 13 SP - 169 EP - 172 PB - WSEAS ER - TY - CHAP A1 - Weber, Konradin A1 - Fischer, Christian A1 - Lange, Martin A1 - Schulz, Uwe A1 - Naraparaju, Ravisankar A1 - Kramer, Dietmar T1 - Design and construction of a testbed for the application of real volcanic ash from the Eyjafjallajökull and Grimsvötn eruptions to microgas turbines T2 - Geophysical Research Abstracts: EGU General Assembly 2017 N2 - It is well known that volcanic ash clouds emitted from erupting volcanoes pose a considerable threat to the aviation. The volcanic ash particles can damage the turbine blades and their thermal barrier coatings as well as the bearings of the turbine. For a detailed investigation of this damaging effect a testbed was designed and constructed, which allowed to study the damaging effects of real volcanic ash to an especially for these investigations modified microgas turbine. The use of this microgas turbine had the advantage that it delivers near reality conditions, using kerosene and operating at similar temperatures as big turbines, but at a very cost effective level. The testbed consisted out of a disperser for the real volcanic ash and all the equipment needed to control the micro gas turbine. Moreover, in front and behind the microgas turbine the concentration and the distribution of the volcanic ash were measured online by optical particle counters (OPCs). The particle concentration and size distribution of the volcanic ash particles in the intake in front of the microgas turbine was measured by an optical particle counter (OPC) combined with an isokinetic intake. Behind the microgas turbine in the exhaust gas additionally to the measurement with a second OPC ash particles were caught with an impactor, in order to enable the later analysis with an electron microscope concerning the morphology to verify possible melting processes of the ash particles. This testbed is of high importance as it allows detailed investigations of the impact of volcanic ash to jet turbines and appropriate countermeasures. KW - Luftreinhaltung KW - Vulkanismus KW - Mikroturbine KW - Messtechnik KW - Vulkanasche Y1 - 2017 UR - https://web.archive.org/web/20220725214516/https://meetingorganizer.copernicus.org/EGU2017/EGU2017-13737.pdf VL - 19 PB - Copernicus CY - Göttingen ER - TY - CHAP A1 - Eliasson, Jonas A1 - Palsson, Thorgeir A1 - Weber, Konradin T1 - State of volcanic ash dispersion prediction T2 - Geophysical Research Abstracts: EGU General Assembly 2017 N2 - The Eyjafjallajokull 2010 and Grimsvotn 2011 eruptions created great problems for commercial aviation in Western Europe and in the North Atlantic region. Comparison of satellite images of the visible and predicted ash clouds showed the VAAC prediction to be much larger than the actual ash clouds. No official explanation of this discrepancy exists apart from the definition of the ash cloud boundary. Papers on simulation of the Eyjafjallajökull ash cloud in peer reviewed journals, typically attempted to simulate the VAAC predictions rather than focusing on the satellite pictures. Sporadic measurements made in-situ showed much lower ash concentrations over Europe than the predicted values. Two of the weak points in ash cloud prediction have been studied in airborne measurements of volcanic ash by the Universities in Kyoto Japan, Iceland and Düsseldorf Germany of eruptions in Sakurajima, Japan. It turns out that gravitational deformation of the plume and a streak fallout process make estimated ash content of clouds larger than the actual, both features are not included in the simulation model. Tropospheric plumes tend to ride in stable inversions this causes gravitational flattening (pancaking) of the volcanic plume, while diffusion in the mixing layer is insignificant. New rules from ICAO, effective from November 2014, reiterate that jetliners should avoid visible ash, this makes information on visible ash important. A procedure developed by JMA′s Tokyo VAAC uses satellite images of visible ash to correct the prediction. This and the fact that meteorological data necessary to model gravitational dispersion and streak fallout do not exist in the international database available to the VAAC′s. This shows that close monitoring by airborne measurements and satellite and other photographic surveillance is necessary. KW - Luftreinhaltung KW - Vulkanismus KW - Vulkanasche KW - Luftfahrt KW - Messtechnik Y1 - 2017 UR - https://web.archive.org/web/20220725214514/https://meetingorganizer.copernicus.org/EGU2017/EGU2017-13656.pdf PB - Copernicus CY - Göttingen ER - TY - CHAP A1 - Arnason, Gylfi A1 - Eliasson, Jonas A1 - Weber, Konradin A1 - Böhlke, Christoph A1 - Palsson, Thorgeir A1 - Rögnvaldsson, Ólafur A1 - Thorsteinsson, Throstur A1 - Platt, Ulrich A1 - Tirpitz, Lukas A1 - Jones, Roderic L. A1 - Smith, Paul D. T1 - Results of airborne measurements in the plume near and far from the 2014 Bardarbunga-Holuhraun eruption T2 - Geophysical Research Abstracts: EGU General Assembly 2015 N2 - The Volcanic Ash Research (VAR) group is focused on airborne measurement of ash contamination to support safe air travel. In relations to the recent eruption, the group measured ash and several gaseous species in the plume 10-300 km from the volcano. The eruption emitted ash turned out to be mostly in the fine aerosol range (much less than 10 micrometers in diameter). Our highest measured concentrations were lower than 1 mg/m3 indicating that commercial air traffic was not threatened (greater than 2 mg/m3) by the ash contamination. But we measured sulfur dioxide (SO2 ) up to 90 mg/m3, which presented a potentially dangerous pollution problem. However, airborne measurements indicate that the sulfur concentration decays (probably due to scavenging) as the plume is carried by the wind from the volcano, which limits the area of immediate danger to the public. Here we present size distribution for particulate matter collected during flights, near and far from the crater at various times. The particle data is then compared with simultaneously collected sulfur dioxide data and the rate of decay of is estimated. Sulfur and particle concentration variations with height in the far plume are presented. Some airborne measurements for H2S, NO, NO2 and CO2 will also be presented. This includes correlation matrices for simultaneous measurements of these gases and comparison to National Air Quality Standards and background values. KW - Luftreinhaltung KW - Vulkanasche KW - Vulkanismus KW - Atmosphärisches Aerosol KW - Messtechnik Y1 - 2015 N1 - Vortragsabstract VL - 17 PB - Copernicus CY - Göttingen ER - TY - CHAP A1 - Weber, Konradin A1 - Reichardt, R. A1 - Fischer, Christian A1 - Moser, H. M. A1 - Eliasson, Jonas ED - Jha, Manoj K. ED - Lazard, Myriam ED - Zaharim, Azami ED - Sopian, Kamaruzzaman T1 - Computational Visualization of Volcanic Ash Plume Concentrations Measured by light Aircrafts over Germany and Iceland during the Recent Eruptions of the Volcanoes Eyjafjallajökull and Grimsvötn T2 - Recent advances in Fluid Mechanics, Heat & Mass Transfer, Biology and Ecology KW - Luftreinhaltung KW - Vulkanasche KW - Visualisierung KW - Eyjafjallajökull KW - Atmosphärisches Aerosol Y1 - 2012 SN - 978-1-61804-065-7 SP - 236 EP - 240 PB - WSEAS ER - TY - CHAP A1 - Vogel, Andreas A1 - Weber, Konradin A1 - Fischer, Christian A1 - van Haren, Günther A1 - Pohl, Tobias A1 - Grobety, Bernhard A1 - Meier, Mario T1 - Airborne in-situ measurements of the Eyjafjallojökull ash plume with a small aircraft and optical particle spectrometers over north-western Germany - comparison between the aircraft measurements and the VAAC-model calculations T2 - Geophysical Research Abstracts: EGU General Assembly 2011 N2 - The eruption of the volcano Eyjafjallajökull (Iceland) in 2010 has caused a transportation of an ash dust plume over large areas of Europe. In April 2010 many airports in Europe were closed for several days because of the volcano ash plume and even in May 2010 several German and European airports were closed for shorter periods because of the danger caused by the volcanic ash dust. The VAAC (Volcanic Ash Advisory Center), London, has continuously published graphics of the predicted spread and dispersion of the volcanic ash plume, which were partly basis for the air traffic restrictions in Germany. In this situation the Laboratory for Environmental Measurement Techniques of the University of Applied Sciences in Duesseldorf has performed 14 measurement flights starting from April 23 2010 to May 21 2010 to get real airborne in-situ dust measurement data over the north-western part of Germany and for comparison with the predicted ash dispersion model data of the VAAC of London in Germany. Moreover, airborne passive DOAS remote sensing measurements have been performed by a mini-DOAS system for SO2-measurements within the plume. In this paper the results of the airborne optical ash particle measurements as well as the remote sensing SO2 measurements will be reported for situations with and without the volcanic plume over northern Germany in detail. Moreover, the measured dust data will be compared with the model dispersion predictions for the ash plume by the VAAC and with European limit concentrations. Main conclusions are: The „ash plume“, found by the aircraft measurement of the Duesseldorf University of Applied Sciences over north western Germany in the “red zone” predicted by the VAAC turned out to be inhomogeneous during the measurement flights Clusters of ash plume sometimes had only a height extension of several hundred meters or less Ash substructures with a horizontal extension of ten kilometres up to several tenth of kilometres could be found Vertical double structures of ash plume could be measured by spiral flights and could be observed visually in horizontal direction Ash plume could be observed visually as small brown layer in horizontal direction Particles collected during flight could be identified as ash particles by electron microscope analysis and chemical analysis KW - Luftreinhaltung KW - Vulkanasche KW - Atmosphärisches Aerosol KW - Eyjafjallajökull KW - Messtechnik Y1 - 2011 VL - 13 PB - Copernicus CY - Göttingen ER - TY - JOUR A1 - Weber, Konradin A1 - Fischer, Christian A1 - Pohl, Tobias A1 - Böhlke, Christoph A1 - Lange, Martin A1 - Scharifi, Emad A1 - Eliasson, Jonas A1 - Yoshitani, Junichi T1 - The Application of Light Research Aircraft for the Investigation of Volcano Eruption Plumes, Industrial Emissions and Urban Plumes JF - WSEAS Transactions on Environment and Development N2 - Airborne measurements have proved to be an important tool for the investigation of volcanic emission plumes, industrial pollution plumes, fugitive emissions and urban pollution plumes. In this paper several examples are demonstrated, how these investigations can be performed by light and microlight propeller aircraft. Throughout the last years innovative aircraft were developed in the light and microlight class showing an excellent flight performance. This enables airborne measurements, which were performed in former years normally by big jet engine driven research aircraft. Moreover, these light and microlight aircraft are equipped with piston motors, which are sturdy enough to operate even in adverse and harsh flight conditions, e.g. in volcanic plumes with high ash concentration. Additionally, turbo charged versions of these airborne piston motors are available, which allow flight altitudes of 7000m – 9000m enabling a large variety of research missions. Another advantage of light and microlight research aircraft is that they are quite cost effective and have a comparatively short certification process for the installation of new measurement equipment. This made it possible to respond fast to the eruption of the Icelandic volcano Eyjafjallajökull 2010 and Grimsvötn 2011 with research flights in volcanic ash plumes over Germany and Iceland. In this way it was possible to deliver real airborne measurements additional to the ash plume model calculations of the London Volcanic Ash Advisory Center (VAAC). In this paper examples of airborne measurements in the volcanic plumes of the recent eruptions of Icelandic volcanoes are given. Moreover examples are presented, which highlight the outstanding capabilities of these aircraft for pinpointing industrial emissions and for characterizing urban pollution plumes. KW - Luftreinhaltung KW - Vulkanismus KW - Vulkanasche KW - Forschungsflugzeug KW - Leichtflugzeug KW - Messtechnik Y1 - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:hbz:due62-opus-50892 SN - 2224-3496 N1 - Open Access Statement: "This is an open access journal which means that all content is freely available without charge to the user or his/her institution. Users are allowed to read, download, copy, distribute, print, search, deposit to institutional repositories or link to the full texts of the articles, or use them for any other lawful purpose, without asking prior permission from the publisher or the author. This is in accordance with the BOAI definition of open access." https://wseas.com/open-access-statement.php VL - 11 SP - 89 EP - 94 PB - WSEAS ER -