A5064228366- Atmospheric chemistry and aerosols
- Atmospheric and Environmental Gas Dynamics
- Atmospheric Ozone and Climate
- Air Quality Monitoring and Forecasting
- Photonic Crystals and Applications
- Plasmonic and Surface Plasmon Research
- Air Quality and Health Impacts
- Optical Coatings and Gratings
- Vehicle emissions and performance
- Spectroscopy and Laser Applications
- Photonic and Optical Devices
- Seismic Imaging and Inversion Techniques
- Nonlinear Optical Materials Studies
- Offshore Engineering and Technologies
- Thyroid Disorders and Treatments
- Biochemical effects in animals
- Advanced Sensor Technologies Research
- Ionosphere and magnetosphere dynamics
- Image and Video Quality Assessment
- Textile materials and evaluations
- Cardiovascular and Diving-Related Complications
- Global Energy and Sustainability Research
- Marine and Offshore Engineering Studies
- Calibration and Measurement Techniques
- Radiation Detection and Scintillator Technologies
University of Bremen
2014-2023
University of Bonn
2006-2017
We review the standard nitrogen dioxide (NO 2 ) data product (Version 1.0.), which is based on measurements made in spectral region 415–465 nm by Ozone Monitoring Instrument (OMI) NASA Earth Observing System‐Aura satellite. A number of ground‐ and aircraft‐based have been used to validate product's three principal quantities: stratospheric, tropospheric, total NO column densities under nearly or completely cloud‐free conditions. The validation OMI complicated a factors, greatest that...
Dutch Aerosol and Nitrogen Dioxide Experiments for Validation of OMI SCIAMACHY (DANDELIONS) is a project that encompasses validation spaceborne measurements NO 2 by the Ozone Monitoring Instrument (OMI) Scanning Imaging Absorption Spectrometer Atmospheric Cartography (SCIAMACHY), aerosol Advanced Along‐Track Radiometer (AATSR), using an extensive set ground‐based balloon over polluted area Netherlands. We present data ground‐based, balloon, satellite on , aerosols, ozone obtained from two...
Abstract. Iodine species in the troposphere are linked to ozone depletion and new particle formation. In this study, a full year of iodine monoxide (IO) columns retrieved from measurements SCIAMACHY satellite instrument is presented, coupled with discussion their uncertainties detection limits. The largest amounts IO found near springtime Antarctic. A seasonal variation Antarctica revealed high values springtime, slightly less summer period again larger autumn. winter, no elevated levels...
Abstract. In June 2009, 22 spectrometers from 14 institutes measured tropospheric and stratospheric NO2 the ground for more than 11 days during Cabauw Intercomparison Campaign of Nitrogen Dioxide measuring Instruments (CINDI), at Cabauw, NL (51.97° N, 4.93° E). All visible instruments used a common wavelength range set cross sections spectral analysis. Most were multi-axis design with analysis by differential spectroscopy software (MAX-DOAS), whose non-zenith slant columns compared examining...
Abstract. In September 2016, 36 spectrometers from 24 institutes measured a number of key atmospheric pollutants for period 17 d during the Second Cabauw Intercomparison campaign Nitrogen Dioxide measuring Instruments (CINDI-2) that took place at Cabauw, Netherlands (51.97∘ N, 4.93∘ E). We report on outcome formal semi-blind intercomparison exercise, which was held under umbrella Network Detection Atmospheric Composition Change (NDACC) and European Space Agency (ESA). The three major goals...
Abstract. Iodine compounds were measured above, below and within the sea ice of Weddell Sea during a cruise in 2009, to make progress elucidating mechanism local enhancement volatilisation iodine. I2 mixing ratios up 12.4 pptv 10 m above ice, 31 was observed surface snow on nearby Brunt Ice Shelf – large amounts. Atmospheric IO 7 from ship, average sum HOI ICl 1.9 pptv. These measurements confirm as an iodine hotspot. Average atmospheric concentrations CH3I, C2H5I, CH2ICl, 2-C3H7I, CH2IBr...
Abstract. We present intercomparison results for formaldehyde (HCHO) slant column measurements performed during the Cabauw Intercomparison campaign of Nitrogen Dioxide measuring Instruments (CINDI) that took place in Cabauw, Netherlands, summer 2009. During two months, nine atmospheric research groups simultaneously operated MAX-DOAS (MultiAXis Differential Optical Absorption Spectroscopy) instruments various designs to record UV-visible spectra scattered sunlight at different elevation...
Abstract. From June to July 2009 more than thirty different in-situ and remote sensing instruments from all over the world participated in Cabauw Intercomparison campaign for Nitrogen Dioxide measuring Instruments (CINDI). The took place at KNMI's Experimental Site Atmospheric Research (CESAR) Netherlands. Its main objectives were determine accuracy of state-of-the-art ground-based measurement techniques detection atmospheric nitrogen dioxide (both sensing), investigate their usability...
Abstract. Airborne imaging differential optical absorption spectroscopy (DOAS), ground-based stationary DOAS, and car DOAS measurements were conducted during the S5P-VAL-DE-Ruhr campaign in September 2020. The area is located Rhine-Ruhr region of North Rhine-Westphalia, western Germany, which a pollution hotspot Europe comprising urban large industrial sources. are used to validate spaceborne NO2 tropospheric vertical column density (VCD) data products from Sentinel-5 Precursor (S5P)...
Abstract Current chemistry climate models do not include polar emissions and of halogens. This work presents the first implementation an interactive module into very short‐lived (VSL) halogen version Community Atmosphere Model with Chemistry (CAM‐Chem) model. The includes photochemical release molecular bromine, chlorine, interhalogens from sea‐ice surface, brine diffusion iodine biologically produced underneath within porous sea‐ice. It also heterogeneous recycling inorganic reservoirs...
Abstract. This article reports on satellite observations of iodine monoxide (IO) and bromine (BrO). The region interest is Antarctica in the time between spring autumn. Both molecules, IO BrO, are reactive halogen species strongly influence tropospheric composition. As a result, better understanding their spatial distribution temporal evolution necessary to assess accurately role chemistry. Especially case IO, information its present magnitude, patterns source regions still sparse. study...
Abstract. The Airborne imaging differential optical absorption spectroscopy (DOAS) instrument for Measurements of Atmospheric Pollution (AirMAP) has been developed the purpose trace gas measurements and pollution mapping. characterized successfully operated from aircraft. Nitrogen dioxide (NO2) columns were retrieved AirMAP observations. A major benefit push-broom is spatially continuous, gap-free measurement sequence independent flight altitude, a valuable characteristic mapping purposes....
Abstract. We present an intercomparison study of four airborne imaging DOAS instruments, dedicated to the retrieval and high-resolution mapping tropospheric nitrogen dioxide (NO2) vertical column densities (VCDs). The AROMAPEX campaign took place in Berlin, Germany, April 2016 with primary objective test intercompare performance experimental imagers. instruments were operated simultaneously from two manned aircraft, performing synchronised flights: APEX (VITO–BIRA-IASB) was DLR's DO-228...
We analyze the influence of correlations on optical properties disordered metallic photonic crystal slabs experimentally and theoretically. Different disorder models with different nearest-neighbor are considered. present a theory that allows us to quantitatively calculate samples. find kinds produce characteristic spectral features such as peak reduction inhomogeneous broadening. These caused by reduced excitation efficiencies multiple resonances.
Abstract. The atmospheric chemistry of iodine and bromine in Polar regions is interest due to the key role halogens many processes, particularly tropospheric ozone destruction. Bromine emitted from open ocean but enriched above first-year sea ice during springtime explosion events, whereas emission attributed biological communities hosted by ice. It has been previously demonstrated that are present Antarctic over glacial–interglacial cycles. Here we investigate seasonal variability polar...
Abstract. In this study we report on airborne imaging DOAS measurements of NO2 from two flights performed in Bucharest during the AROMAT campaign (Airborne ROmanian Measurements Aerosols and Trace gases) September 2014. These were with Airborne Differential Optical Absorption Spectroscopy (DOAS) instrument for Atmospheric Pollution (AirMAP) provide nearly gapless maps column densities below aircraft a high spatial resolution better than 100 m. The air mass factors, which are needed to...
Abstract. Volcanic eruptions inject substantial amounts of halogens into the atmosphere. Chlorine and bromine oxides have frequently been observed in volcanic plumes from different instrumental platforms such as ground, aircraft satellites. The present study is first observational evidence that iodine are also emitted atmosphere during eruptions. Large column monoxide, IO, satellite measurements following major eruption Kasatochi volcano, Alaska, 2008. IO signal detected made both by...
Abstract. This study describes a novel application of an “onion-peeling” approach to multi-axis differential optical absorption spectroscopy (MAX-DOAS) measurements shipping emissions aiming at investigating the strong horizontal inhomogeneities in NO2 over lane. To monitor ship on main route towards port Hamburg, two-channel (UV and visible) MAX-DOAS instrument was deployed island Neuwerk German Bight, 6–7 km south Utilizing fact that effective light path length atmosphere depends...
Abstract. A novel imaging-DOAS (differential optical absorption spectroscopy) instrument IMPACT (Imaging MaPper for AtmospheriC observaTions) is presented combining full-azimuthal pointing (360∘) with a large vertical coverage (∼41∘). Complete panoramic scans are acquired at temporal resolution of ∼15 min, enabling the retrieval NO2 profiles over entire panorama around measurement site. showed excellent agreement (correlation >99 %) coincident multiaxis DOAS (MAX-DOAS) measurements during...
Abstract. The Airborne ROmanian Measurements of Aerosols and Trace gases (AROMAT) campaigns took place in Romania September 2014 August 2015. They focused on two sites: the Bucharest urban area large power plants Jiu Valley. main objectives were to test recently developed airborne observation systems dedicated air quality studies verify their applicability for validation space-borne atmospheric missions such as TROPOspheric Monitoring Instrument (TROPOMI)/Sentinel-5 Precursor (S5P). We...
Abstract. Iodine compounds were measured above, below and within the sea ice of Weddell Sea during a cruise in 2009, to elucidate mechanism local enhancement volatilisation iodine. I2 mixing ratios up 12.4 pptv 10 m above ice, 31 was observed surface snow on nearby Brunt Ice Shelf – large amounts. Atmospheric IO 7 from ship, average sum HOI ICl 1.9 pptv. These measurements confirm as an iodine hotspot. Average atmospheric concentrations CH3I, C2H5I, CH2ICl, 2-C3H7I, CH2IBr 1-C3H7I each 0.2...
Abstract We study the influence of positional disorder on optical properties metallic photonic crystals. Two models are implemented, namely frozen‐phonon and long‐range disorder. calculate two‐point correlation functions, analyze Fourier transforms spatial arrangements, present experimental extinction spectra different disordered (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Abstract We analyze the influence of disorder on polaritonic bandstructure metallic photonic crystal slabs. Different types with varying next‐neighbor correlations and amounts are implemented. Angle‐resolved transmission measurements allow to determine relation disorder. found that uncorrelated retains only reduces splitting between gaps. Correlated disorder, however, leads complete destruction for moderate due excitation different modes. present a model shows good agreement measurements. (©...