A5008787662- Atmospheric chemistry and aerosols
- Atmospheric Ozone and Climate
- Atmospheric and Environmental Gas Dynamics
- Atmospheric aerosols and clouds
- Air Quality Monitoring and Forecasting
- Skin and Cellular Biology Research
- Vehicle emissions and performance
- Air Quality and Health Impacts
- Spectroscopy and Laser Applications
- Fire effects on ecosystems
- Reconstructive Facial Surgery Techniques
- Odor and Emission Control Technologies
- Lightning and Electromagnetic Phenomena
- Meteorological Phenomena and Simulations
- Climate variability and models
- Advanced Aircraft Design and Technologies
- Autoimmune Bullous Skin Diseases
- Calibration and Measurement Techniques
- Genetic and Kidney Cyst Diseases
- Advanced Chemical Sensor Technologies
- Climate Change Policy and Economics
- Catalytic Processes in Materials Science
- Nasal Surgery and Airway Studies
- Mass Spectrometry Techniques and Applications
- Advanced Measurement and Detection Methods
Eastern Michigan University
2025
University Hospital of Basel
2012-2020
Dermatologie Freiburg
2008-2020
Petersfield Community Hospital
2018
Forschungszentrum Jülich
2006-2016
Association des Operateurs Postaux Publics Europeens
2015
Leibniz Institute for Tropospheric Research
2004-2012
Hautklinik Heidelberg
2007-2011
University Medical Center Freiburg
2002-2010
University of Freiburg
2002-2007
The photolysis of nitrous acid (HONO) in the early morning hours is an important source OH radicals, most daytime oxidizing species. Although importance this mechanism has been recognized for many years, no accurate quantification available, and role HONO often underestimated. We present measurements its precursor NO 2 by Differential Optical Absorption Spectroscopy (DOAS) during Berliner Ozonexperiment (BERLIOZ) field campaign July/August 1998 at Pabstthum near Berlin, Germany....
The European Research Infrastructure IAGOS (In-service Aircraft for a Global Observing System) operates global-scale monitoring system atmospheric trace gases, aerosols and clouds utilising the existing global civil aircraft. This new infrastructure builds on heritage of former research projects MOZAIC (Measurement Ozone Water Vapour Airbus In-service Aircraft) CARIBIC (Civil Regular Investigation Atmosphere Based an Instrument Container). continues within acts as important airborne...
Abstract. Changes in baseline (here understood as representative of continental to hemispheric scales) tropospheric O3 concentrations that have occurred at northern mid-latitudes over the past six decades are quantified from available measurement records with goal providing benchmarks which retrospective model calculations global distribution can be compared. Eleven data sets (ten ground-based and one airborne) including European (beginning 1950's before), three North American 1984) two...
Abstract Two recent papers have quantified long‐term ozone (O 3 ) changes observed at northern midlatitude sites that are believed to represent baseline (here understood as representative of continental hemispheric scales) conditions. Three chemistry‐climate models (NCAR CAM‐chem, GFDL‐CM3, and GISS‐E2‐R) calculated retrospective tropospheric O concentrations part the Atmospheric Chemistry Climate Model Intercomparison Project Coupled Phase 5 model intercomparisons. We present an approach...
The fast‐response resonance fluorescence instrument for the airborne measurement of carbon monoxide described by Gerbig et al. [1996] was modified implementing an improved optical filter with more efficient optics and optimized lamp. Besides reductions in size weight, new achieves a sensitivity 10 times higher, lower background (65 ppb compared 250 ppb), faster time response (<0.1 s) than original instrument. precision is ±1.5 at atmospheric mixing ratio 100 CO, detection limit 3 (2σ)...
OH has been detected in the lower troposphere by optical absorption of Q 1 2 (A²Σ + , v = O, X²Π, O) line at 307.995 nm along a 7.8 km path above Jülich (51° North, 6° East). The detection limit depended on quality photographic exposure and reached · 10 6 cm −3 most favourable cases. generally remained below 4 average limit. But several occasions during observation period from mid August to November 1975 concentrations up 7 were observed.
Ground‐based measurements of the concentration 14 CO are reported. The data exhibit a well‐defined seasonal variation at mid‐latitudes with maximum 25 ± 2 molecule cm −3 during winter and minimum 11 1 summer. also indicate strong latitudinal variation, lower concentrations occurring in tropics. interpreted using 2‐D time‐dependent model. To balance sources both 12 CO, an average tropospheric OH (6.5 ‐2 +3 ) × 10 5 is required. In addition, production rate from biological processes including...
This article presents the In-service Aircraft of a Global Observing System (IAGOS) developed for operations on commercial long-range Airbus aircraft (A330/A340) monitoring atmospheric composition. IAGOS is continuation former Measurement OZone and water vapour airCraft (MOZAIC) programme (1994–2014) with five operated by European airlines over 20 yr. MOZAIC has provided unique scientific database used worldwide community. In MOZAIC, aims to equip fleet up around world decades. started in...
At northern midlatitudes the abundance of tropospheric O 3 has increased by a factor approximately 2 since 1950s. The cause this increase is generally attributed to increasing anthropogenic precursor emissions, but present chemical and transport models cannot quantitatively reproduce its magnitude. Here we show another manifestation changes in abundance—a shift seasonal cycle at so that observed peak concentrations now appear earlier year than previous decades. rate been 6 days per decade...
Gas‐phase isotopic exchange between NO and 2 enriches the heavier 15 N isotope in more oxidized form. In atmosphere concentration of both gases, , is controlled during daytime by Leighton relationship through oxidation with O 3 photolytic reaction to NO. For atmospheric concentrations (e.g., x ∼10 ppb), are very fast characteristic time constants a few minutes compared other removing reactions via OH radicals (daytime reaction) (nighttime some hours more. We have found from N/ 14...
During the fall 1997 North Atlantic Regional Experiment (NARE 97), two separate intercomparisons of aircraft‐based carbon monoxide measurement instrumentation were conducted. On September 2, CO measurements simultaneously made aboard National Oceanic and Atmospheric Administration (NOAA) WP‐3 by vacuum ultraviolet (VUV) fluorescence tunable diode laser absorption spectroscopy (TDLAS). 18, an intercomparison flight was conducted between instruments, both employing VUV method, on NOAA U.K....
The Photochemistry Experiment during BERLIOZ (PHOEBE) was conducted in July and August 1998 at a rural site located near the small village of Pabstthum, about 50 km northwest downtown Berlin. In this paper, spectroscopic measurements hydroxyl (OH) peroxy radicals (HO 2 RO ) are discussed for two intensive days (20 21 July) campaign. On both peak values radical concentrations were similar, reaching 6–8 × 10 6 cm −3 OH 20–30 ppt HO . Fairly high observed morning hours presence high‐NO x mixing...
Abstract. We present the configuration of Météo-France Chemistry and Transport Model (CTM) MOCAGE-Climat that will be dedicated to study chemistry climate interactions. is a state-of-the-art CTM simulates global distribution ozone its precursors (82 chemical species) both in troposphere stratosphere, up mid-mesosphere (~70 km). Surface processes (emissions, dry deposition), convection, scavenging are explicitly described model has been driven by ECMWF operational analyses period 2000–2005,...
Abstract. This study presents an analysis of both MOZAIC profiles above Frankfurt and Lagrangian dispersion model simulations for the 2003 European heat wave. The comparison measurements in summer with 11-year climatology reflects strong temperature anomalies (exceeding 4°C) throughout lower troposphere. Higher positive negative wind speed relative humidity are found period defined here as wave (2–14 August 2003), compared to periods before (16–31 July 2003) after In addition, backward mode...
Results from balloon‐borne experiments carried out in southern France at a latitude of about 44° are presented. Four successful flights were performed with neon‐cooled cryogenic air sampler designed to collect large samples eight different stratospheric heights. Supplementary tropospheric taken aboard chartered aircraft. The samples, which cover an altitude range 2.8 km 35.3 km, analyzed gas chromatographically for H 2 , CH 4 CO, N O, CFCl 3 and CF Cl .
Vertical profiles of H 2 , CH 4 CO, N O, CFCl 3 and CF Cl resulting from gas chromatographic analysis air samples collected altitudes between 1.5 35.3 km at a latitude about 44°N are presented. Ten balloon flights were performed with neon‐cooled cryogenic sampler designed to collect large eight different stratospheric heights. Supplementary tropospheric taken aboard chartered aircraft. 1978 1979 compared those derived fights in 1977.
Nitrogen oxide (NO and NOy) measurements were performed onboard an in-service aircraft within the framework of CARIBIC (Civil Aircraft for Regular Investigation atmosphere Based on Instrument Container). A total 330 flights completed from May 2005 through April 2013 between Frankfurt/Germany destination airports in Canada, USA, Brazil, Venezuela, Chile, Argentina, Colombia, South Africa, China, Korea, Japan, India, Thailand, Philippines. Different regions show differing NO NOy mixing ratios....