120 results on '"Bösch, Tim"'
Search Results
2. Measurement report: Combined use of MAX-DOAS and AERONET ground-based measurements in Montevideo, Uruguay, for the detection of distant biomass burning.
- Author
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Osorio, Matías, Agesta, Alejandro, Bösch, Tim, Casaballe, Nicolás, Richter, Andreas, Alvarado, Leonardo M. A., and Frins, Erna
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BIOMASS burning ,TRACE gases ,AIR pollutants ,FORMALDEHYDE ,OPTICAL spectroscopy ,CHEMICAL species ,LIGHT absorption - Abstract
Biomass burning releases large amounts of aerosols and chemical species into the atmosphere, representing a major source of air pollutants. Emissions and by-products can be transported over long distances, presenting challenges in quantification. This is mainly done using satellites, which offer global coverage and data acquisition for places that are difficult to access. In this study, ground-based observations are used to assess the abundance of trace gases and aerosols. On 24 November 2020, a significant increase in formaldehyde was observed with a Multi-AXis Differential Optical Absorption Spectroscopy (MAX-DOAS) instrument located in Montevideo (Uruguay), and its vertical column densities reached values of 2.4×1016 molec. cm -2 , more than twice the values observed during the previous days. This was accompanied by an increase in the aerosol levels measured by an AErosol RObotic NETwork (AERONET) photometer located at the same site. The aerosol optical depth (AOD) at 440 nm reached values close to 1, an order of magnitude larger than typical values in Montevideo. Our findings indicate that the increase was associated with the passage of a plume originating from distant biomass burning. This conclusion is supported by TROPOspheric Monitoring Instrument (TROPOMI) satellite observations as well as HYbrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) simulations. The profiles of the gases and aerosols retrieved from the MAX-DOAS observations are consistent with the HYSPLIT analysis, showing the passage of a plume over Montevideo on 24 November located at a height of ∼ 1.5 km. This corroborates the finding that biomass burning events occurring about 800 km north of Montevideo can affect the local atmosphere through long-distance emissions transport. This study underscores the potential of ground-based atmospheric monitoring as a tool for detection of such events. Furthermore, it demonstrates greater sensitivity compared to satellite when it comes to detection of relatively small amounts of carbonyls like glyoxal and formaldehyde. [ABSTRACT FROM AUTHOR]
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- 2024
- Full Text
- View/download PDF
3. Measurement Report: Potential of MAX-DOAS and AERONET ground based measurements in Montevideo, Uruguay for the detection of distant biomass burning
- Author
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Osorio, Matías, primary, Agesta, Alejandro, additional, Bösch, Tim, additional, Casaballe, Nicolás, additional, Richter, Andreas, additional, Alvarado, Leonardo, additional, and Frins, Erna, additional
- Published
- 2023
- Full Text
- View/download PDF
4. Validation of GEMS tropospheric NO2 columns and their diurnal variation with ground-based DOAS measurements.
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Lange, Kezia, Richter, Andreas, Bösch, Tim, Zilker, Bianca, Latsch, Miriam, Behrens, Lisa K., Okafor, Chisom M., Bösch, Hartmut, Burrows, John P., Merlaud, Alexis, Pinardi, Gaia, Fayt, Caroline, Friedrich, Martina M., Dimitropoulou, Ermioni, Roozendael, Michel Van, Ziegler, Steffen, Ripperger-Lukosiunaite, Simona, Kuhn, Leon, Lauster, Bianca, and Wagner, Thomas
- Subjects
GEOSTATIONARY satellites ,SPRING ,AIR pollutants ,TROPOSPHERIC chemistry ,NITROGEN dioxide ,AIR quality ,AUTUMN - Abstract
Instruments for air quality observations on geostationary satellites provide multiple observations per day and allow for the analysis of the diurnal variation of important air pollutants such as nitrogen dioxide (NO
2 ) over large areas. The South Korean instrument GEMS on the GK2B satellite was launched in February 2020 and is the first instrument in geostationary orbit that delivers hourly daytime observations of NO2 . The measurements with a spatial resolution of 3.5 km x 8 km cover a large part of Asia. This study compares one year of tropospheric NO2 vertical column density (VCD) observations of the operational GEMS L2 product, the scientific GEMS IUP-UB product, the operational TROPOMI product, and ground-based DOAS measurements in South Korea. The GEMS L2 tropospheric NO2 VCDs overestimate the VCDs retrieved from the ground-based observations with a median relative difference of +64 % and a correlation coefficient of 0.75. The median relative difference is -1 % for the GEMS IUP-UB product and -14 % for the TROPOMI product. The evaluation of the GEMS IUP-UB product and the operational TROPOMI product with ground-based measurements is in good agreement with correlation coefficients of 0.82 and 0.88. The scatter in the GEMS products can be reduced when observations are limited to the TROPOMI overpass time. The observed diurnal variations of the tropospheric NO2 VCDs show a maximum of NO2 during the late morning for urban sites, whereas rural sites show weak or almost no diurnal changes. Investigations of the seasonal diurnal variability show with a minimum in the observed tropospheric NO2 VCDs around noon the importance of chemical loss of NO2 in summer. Most variability is seen in spring and autumn, which dominate the average annual diurnal cycle. Observations under low wind conditions show strong enhancements of NO2 over the day, especially at polluted sites during winter. This indicates that under calm conditions, dilution and the less effective chemical loss in winter do not balance the accumulating emissions. The impact of transport processes is illustrated by the diurnal variability at a rural site following mean wind patterns for specific seasons and observation times. Analyzing the weekday-weekend effect, good agreement was found between the different products. However, the GEMS L2 product while agreeing with the other data sets during weekdays shows significantly less reduction on weekends. Our investigations show that the observed diurnal evolution of NO2 varies significantly at the different measurement sites, with good agreement between the GEMS IUP-UB and ground-based observations. The diurnal variability of tropospheric NO2 VCDs depends on chemistry, emissions, and transport into and out of the measurement region. To interpret the sources and sinks of NO2 requires that all of these factors are considered. [ABSTRACT FROM AUTHOR]- Published
- 2024
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- View/download PDF
5. On the influence of vertical mixing, boundary layer schemes, and temporal emission profiles on tropospheric NO2 in WRF-Chem – comparisons to in situ, satellite, and MAX-DOAS observations.
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Kuhn, Leon, Beirle, Steffen, Kumar, Vinod, Osipov, Sergey, Pozzer, Andrea, Bösch, Tim, Kumar, Rajesh, and Wagner, Thomas
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BOUNDARY layer (Aerodynamics) ,LIGHT absorption ,PEROXYACETYL nitrate ,EMISSION inventories ,SPATIAL resolution ,ACOUSTIC emission ,ARTIFICIAL satellites - Abstract
We present WRF-Chem simulations over central Europe with a spatial resolution of 3 km × 3 km and focus on nitrogen dioxide (NO2). A regional emission inventory issued by the German Environmental Agency, with a spatial resolution of 1 km × 1 km, is used as input. We demonstrate by comparison of five different model setups that significant improvements in model accuracy can be achieved by choosing the appropriate boundary layer scheme, increasing vertical mixing strength, and/or tuning the temporal modulation of the emission data ("temporal profiles") driving the model. The model setup with improved vertical mixing is shown to produce the best results. Simulated NO2 surface concentrations are compared to measurements from a total of 275 in situ measurement stations in Germany, where the model was able to reproduce average noontime NO2 concentrations with a bias of ca. - 3 % and R=0.74. The best agreement is achieved when correcting for the presumed NOy cross sensitivity of the molybdenum-based in situ measurements by computing an NOy correction factor from modelled peroxyacetyl nitrate (PAN) and nitric acid (HNO3) mixing ratios. A comparison between modelled NO2 vertical column densities (VCDs) and satellite observations from TROPOMI (TROPOspheric Monitoring Instrument) is conducted with averaging kernels taken into account. Simulations and satellite observations are shown to agree with a bias of + 5.5 % and R=0.87 for monthly means. Lastly, simulated NO2 concentration profiles are compared to noontime NO2 profiles obtained from multi-axis differential optical absorption spectroscopy (MAX-DOAS) measurements at five locations in Europe. For stations within Germany, average biases of - 25.3 % to + 12.0 % were obtained. Outside of Germany, where lower-resolution emission data were used, biases of up to + 50.7 % were observed. Overall, the study demonstrates the high sensitivity of modelled NO2 to the mixing processes in the boundary layer and the diurnal distribution of emissions. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
6. Investigation of meteorological conditions and BrO during ozone depletion events in Ny-Ålesund between 2010 and 2021
- Author
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Zilker, Bianca, primary, Richter, Andreas, additional, Blechschmidt, Anne-Marlene, additional, von der Gathen, Peter, additional, Bougoudis, Ilias, additional, Seo, Sora, additional, Bösch, Tim, additional, and Burrows, John Philip, additional
- Published
- 2023
- Full Text
- View/download PDF
7. Measurement Report: Potential of MAX-DOAS and AERONET ground based measurements in Montevideo, Uruguay for the detection of distant biomass burning.
- Author
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Osorio, Matías, Agesta, Alejandro, Bösch, Tim, Casaballe, Nicolás, Richter, Andreas, Alvarado, Leonardo, and Frins, Erna
- Subjects
BIOMASS burning ,TRACE gases ,AIR pollutants ,FORMALDEHYDE ,CHEMICAL species ,AEROSOLS ,ACQUISITION of data - Abstract
Biomass burning releases large amounts of aerosols and chemical species into the atmosphere, which represents a major source of air pollutants. Emissions and by-products can be transported over long distances, presenting challenges in quantification. This is mainly done using satellites, which offer global coverage and data acquisition for places that are difficult to access. In this study, ground-based observations play an important role in assessing the abundance of trace gases and aerosols. On November 24, 2020, a significant increase in formaldehyde was observed, with a MAX-DOAS instrument located in Montevideo (Uruguay). Vertical column densities reached values of 2.4x10
16 molec. cm-2 , more than twice the values observed during the previous days. This was accompanied by an increase in the aerosol levels measured by an AERONET photometer located at the same site. For example, the AOD at 440 nm reached values close to 1, one order of magnitude larger than typical values in Montevideo. Our findings indicate that the cause of the increase was associated with the passage of a plume originating from distant biomass burning. This conclusion is supported using TROPOMI satellite observations as well as HYSPLIT trajectory simulations. The profiles of the gases and aerosols retrieved from the MAX-DOAS observations are consistent with the HYSPLIT analysis, showing the passage of a plume over Montevideo on November 24 located at a height of ∼1.5 km. This corroborates that biomass burning events that occur about 800 km north of Montevideo can affect the local atmosphere due to long-distance transport of emissions. This study underscores the potential of ground-based atmospheric monitoring as a tool for detection of such events. Furthermore, it demonstrates the greater sensitivity compared to satellite when it comes to detection of relatively small amounts of carbonyls like glyoxal and formaldehyde. [ABSTRACT FROM AUTHOR]- Published
- 2023
- Full Text
- View/download PDF
8. Investigation of weather conditions and BrO during ozone depletion events between 2010 and 2021 in Ny-Ålesund
- Author
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Zilker, Bianca, primary, Richter, Andreas, additional, Blechschmidt, Anne-Marlene, additional, Bougoudis, Ilias, additional, Seo, Sora, additional, von der Gathen, Peter, additional, Bösch, Tim, additional, and Burrows, John P., additional
- Published
- 2023
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9. Measurements of trace gases with a MAX-DOAS system during a ship cruise from the Canaries to Ecuador (SO287) on board of RV Sonne
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Bösch, Tim, primary, Latsch, Miriam, additional, Richter, Andreas, additional, Wittrock, Folkard, additional, and Burrows, John P., additional
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- 2023
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10. Towards more realistic modelling of tropospheric NO2 with WRF-Chem using fine-tuned temporal emission profiles
- Author
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Kuhn, Leon, primary, Beirle, Steffen, additional, Kumar, Vinod, additional, Osipov, Sergey, additional, Pozzer, Andrea, additional, Bösch, Tim, additional, Kumar, Rajesh, additional, and Wagner, Thomas, additional
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- 2023
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11. Supplementary material to "Modelling of tropospheric NO₂ using WRF-Chem with optimized temporal NOₓ emission profiles derived from in-situ observations – Comparisons to in-situ, satellite, and MAX-DOAS observations over central Europe"
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Kuhn, Leon, primary, Beirle, Steffen, additional, Kumar, Vinod, additional, Osipov, Sergey, additional, Pozzer, Andrea, additional, Bösch, Tim, additional, Kumar, Rajesh, additional, and Wagner, Thomas, additional
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- 2023
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12. Modelling of tropospheric NO₂ using WRF-Chem with optimized temporal NOₓ emission profiles derived from in-situ observations – Comparisons to in-situ, satellite, and MAX-DOAS observations over central Europe
- Author
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Kuhn, Leon, primary, Beirle, Steffen, additional, Kumar, Vinod, additional, Osipov, Sergey, additional, Pozzer, Andrea, additional, Bösch, Tim, additional, Kumar, Rajesh, additional, and Wagner, Thomas, additional
- Published
- 2023
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13. Validation of Sentinel-5P TROPOMI tropospheric NO2 products by comparison with NO2 measurements from airborne imaging, ground-based stationary, and mobile car DOAS measurements during the S5P-VAL-DE-Ruhr campaign
- Author
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Lange, Kezia, primary, Richter, Andreas, additional, Schönhardt, Anja, additional, Meier, Andreas C., additional, Bösch, Tim, additional, Seyler, André, additional, Krause, Kai, additional, Behrens, Lisa K., additional, Wittrock, Folkard, additional, Merlaud, Alexis, additional, Tack, Frederik, additional, Fayt, Caroline, additional, Friedrich, Martina M., additional, Dimitropoulou, Ermioni, additional, Van Roozendael, Michel, additional, Kumar, Vinod, additional, Donner, Sebastian, additional, Dörner, Steffen, additional, Lauster, Bianca, additional, Razi, Maria, additional, Borger, Christian, additional, Uhlmannsiek, Katharina, additional, Wagner, Thomas, additional, Ruhtz, Thomas, additional, Eskes, Henk, additional, Bohn, Birger, additional, Santana Diaz, Daniel, additional, Abuhassan, Nader, additional, Schüttemeyer, Dirk, additional, and Burrows, John P., additional
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- 2022
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14. FDR4ATMOS (Task B): FDR Long time series for spectral imagers
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Lichtenberg, Günter, Slijkhuis, Sander, Hamidouche, Mourad, Coldewey-Egbers, Melanie, Aberle, Bernd, Kumar, Aman, Noël, Stefan, Bramstedt, Klaus, Hilbig, Tina, Bösch, Tim, Lambert, Jean-Christopher, Van Gent, J., Hubert, Daan, Green, Paul, de Vis, Pieter, Dehn, Angelika, and Brizzi, Gabriele
- Subjects
Calibration cross-calibration GOME SCIAMACHY FDR atmosphere spectrometers Level1 - Published
- 2022
15. Pan-Atlantic connectivity of marine biogeochemical and ecological processes and the impact of anthropogenic pressures, SO287, 11.12.2021 - 11.01.2022, Las Palmas (Spain) - Guayaquil (Ecuador)
- Author
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Quack, Birgit, Auganaes, Sigrid, Bösch, Tim, Booge, Dennis, Brockmann, Inga, Brown, Lucy, Cardoso, Claudio, Diogoul, Ndague, Hepach, Helmke, Hieronymi, Martin, Ingeniero, Riel Carlo O, Latsch, Miriam, Offin, Alice, Potin, Philippe, Qelaj, Kastriot, Rosa, Alexandra, Reis, Jesus, Röttgers, Rüdiger, Scheidemann, Lindsay, Schulz, Gesa, Sulaiman, Hanif, Wunderlich, Greta, Xu, Peihang, and Zehender, Isabella
- Abstract
The transit of RV SONNE from Las Palmas (departure: 11.12.2021) to Guayaquil, Ecuador (arrival: 11.01.2022) is directly related to the international collaborative project SO287-CONNECT of GEOMAR in cooperation with Hereon and the University of Bremen, supported by the German Federal Ministry of Education and Research (BMBF) between October 15 2021 and January 15 2024. The research expedition was conducted to decipher the coupling of biogeochemical and ecological processes and their influence on atmospheric chemistry along the transport pathway of water from the upwelling zones off Africa into the Sargasso Sea and further to the Caribbean and the equatorial Pacific. Nutrient-rich water rises from the deep and promotes the growth of plant and animal microorganisms, and fish at the ocean surface off West Africa. The North Equatorial Current water carries the water from the upwelling, which contains large amounts of organic material across the Atlantic to the Caribbean, supporting bacterial activity along the way. But how the nutritious remnants of algae and other substances are processed on their long journey, biochemically transformed, decomposed into nutrients and respired to carbon dioxide, has so far only been partially investigated. Air, seawater and particles were sampled in order to provide new details about the large cycles of carbon and nitrogen, but also of many other elements such as oxygen, iodine, bromine and sulfur. Inorganic and organic bromine and iodine compounds are generally emitted naturally from the ocean into the atmosphere, promote cloud formation and affect climate, and some even reach the stratosphere where they contribute to ozone depletion. We measured how much of these compounds are released from the ocean, and at what locations and how they are transformed in the ocean and in the atmosphere. Sargassum algae, which have become a nuisance on beaches in the western and eastern Atlantic, support life and contribute to carbon cycling in the middle of the Atlantic, the Sargasso Sea and in the Caribbean, while their contribution to halogen cycling and marine bromine and iodine emissions was previously unknown. We investigated the influence of various natural parameters such as temperature and solar radiation on the biogeochemical transformation processes in order to understand the influence of climate change on these processes in incubation experiments with seawater and algae. We investigated how anthropogenic signals such as shipping traffic influence the nitrogen and sulphur cycle in the ocean, as well as the impact of nitrogen oxides from ship exhaust and sulphurous, acidic and dirty water from purification systems on organisms and biochemical processes. Plastic debris was sampled from the surface waters to investigate its contribution to global biogeochemical transformation processes. The working hypotheses of the research program were: Bioavailability of dissolved organic carbon in surface waters decreases along the productivity gradient and transport pathway from the Eastern to the Western Tropical North Atlantic. Nutrient gradients from East to West constrain the microbial utilization of organic matter- contributing to an accumulation of C-rich organic matter due to a) limited mineralization and b) enhanced exudation- also leading to gel-like particles accumulation in the western tropical North Atlantic and Sargasso Sea. Tropospheric and stratospheric ozone are strongly impacted by biogeochemical and ecological processes occurring around and in the NA gyre system related to marine iodine and bromine cycles. The long-range transport of natural and anthropogenic organic matter in water and of gases and aerosols in the air impact carbon-export, biogeochemical cycles in the water column, and the release of gases and particles from the ocean significantly. 4 SONNE -Berichte, SO287, Las Palmas - Guayaquil, 11.12.2021 - 11.01.202 The data and samples obtained specifically target carbon, nutrient and halogen cycling, the composition of phytoplankton, bacteria, the transport and sequestration of macro algae and the air-sea exchange processes of climate relevant gases and aerosols. The influence of ecological and transport processes, as well as anthropogenic impacts on the North Atlantic gyre system, specifically in the Sargasso Sea and the influence of ship emissions throughout the Atlantic towards the west and into the Pacific will be investigated with the data.
- Published
- 2022
16. Investigation of meteorological conditions and BrO during Ozone Depletion Events in Ny-Ålesund between 2010 and 2021.
- Author
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Zilker, Bianca, Richter, Andreas, Blechschmidt, Anne-Marlene, von der Gathen, Peter, Bougoudis, Ilias, Seo, Sora, Bösch, Tim, and Burrows, John Philip
- Subjects
ATMOSPHERIC boundary layer ,OZONE layer depletion ,POLAR vortex ,TROPOSPHERIC ozone ,WIND speed ,SPRING ,OZONESONDES - Abstract
During polar spring, Ozone Depletion Events (ODEs) are often observed in combination with Bromine Explosion Events (BEEs) in Ny-Ålesund. In this study, two long term ozone data sets (2010–2021) from ozone sonde launches and in-situ ozone measurements have been evaluated between March and May of each year, to study ODEs in Ny-Ålesund. Ozone concentrations below 15 ppb were marked as ODE. We applied a composite analysis to evaluate tropospheric BrO retrieved from satellite data and the prevailing meteorological conditions during these events. During ODEs, both data sets show a blocking situation with a low pressure anomaly over the Barents Sea and anomalously high pressure in the Icelandic low area, leading to transport of cold polar air from the north to Ny-Ålesund with negative temperature and positive BrO anomalies found around Svalbard. Also higher wind speed and a higher, less stable boundary layer are noticed, supporting the assumption that ODEs often occur in combination with polar cyclones. Applying a 20 ppb ozone threshold value to tag ODEs resulted in only a slight attenuation of the BrO and meteorological anomalies compared to the 15 ppb threshold. Monthly analysis showed that BrO and meteorological anomalies are weakening from March to May. Therefore, ODEs associated with low pressure systems, high wind speeds and blowing snow more likely occur in early spring, while ODEs associated with low wind speed and stable boundary layer meteorological conditions seem to occur more often in late spring. In an annual evaluation, similar prevailing meteorological conditions were found for several years as well as in the overall result of the composite analysis. However, some years show different meteorological patterns deviating from the results of the mean analysis. Finally, an ODE case study from the beginning of April 2020 in Ny-Ålesund is presented, where ozone was depleted for two consecutive days in combination with increased BrO values. The meteorological conditions are representative of the results of the composite analysis. A low pressure system arrived from the north-east to Svalbard resulting in high wind speeds with blowing snow and transport of cold polar air from the north. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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17. Validation of Sentinel-5P TROPOMI tropospheric NO2 products by comparison with NO2 measurements from airborne imaging DOAS, ground-based stationary DOAS, and mobile car DOAS measurements during the S5P-VAL-DE-Ruhr campaign.
- Author
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Lange, Kezia, Richter, Andreas, Schönhardt, Anja, Meier, Andreas C., Bösch, Tim, Seyler, André, Krause, Kai, Behrens, Lisa K., Wittrock, Folkard, Merlaud, Alexis, Tack, Frederik, Fayt, Caroline, Friedrich, Martina M., Dimitropoulou, Ermioni, Van Roozendael, Michel, Kumar, Vinod, Donner, Sebastian, Dörner, Steffen, Lauster, Bianca, and Razi, Maria
- Subjects
RESEARCH aircraft ,AIR pollution ,AIRBORNE-based remote sensing ,PEARSON correlation (Statistics) ,OPTICAL spectroscopy ,LIGHT absorption ,POLLUTION measurement - 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 campaign area is located in the Rhine-Ruhr region of North Rhine-Westphalia, western Germany, which is a pollution hotspot in Europe comprising urban and large industrial sources. The DOAS measurements are used to validate spaceborne NO 2 tropospheric vertical column density (VCD) data products from the Sentinel-5 Precursor (S5P) TROPOspheric Monitoring Instrument (TROPOMI). Seven flights were performed with the airborne imaging DOAS instrument for measurements of atmospheric pollution (AirMAP), providing measurements that were used to create continuous maps of NO 2 in the layer below the aircraft. These flights cover many S5P ground pixels within an area of 30 km × 35 km and were accompanied by ground-based stationary measurements and three mobile car DOAS instruments. Stationary measurements were conducted by two Pandora, two Zenith-DOAS, and two MAX-DOAS instruments. Ground-based stationary and car DOAS measurements are used to evaluate the AirMAP tropospheric NO 2 VCDs and show high Pearson correlation coefficients of 0.88 and 0.89 and slopes of 0.90 ± 0.09 and 0.89 ± 0.02 for the stationary and car DOAS, respectively. Having a spatial resolution of about 100 m × 30 m, the AirMAP tropospheric NO 2 VCD data create a link between the ground-based and the TROPOMI measurements with a nadir resolution of 3.5 km × 5.5 km and are therefore well suited to validate the TROPOMI tropospheric NO 2 VCD. The observations on the 7 flight days show strong NO 2 variability, which is dependent on the three target areas, the day of the week, and the meteorological conditions. The AirMAP campaign data set is compared to the TROPOMI NO 2 operational offline (OFFL) V01.03.02 data product, the reprocessed NO 2 data using the V02.03.01 of the official level-2 processor provided by the Product Algorithm Laboratory (PAL), and several scientific TROPOMI NO 2 data products. The AirMAP and TROPOMI OFFL V01.03.02 data are highly correlated (r=0.87) but show an underestimation of the TROPOMI data with a slope of 0.38 ± 0.02 and a median relative difference of - 9 %. With the modifications in the NO 2 retrieval implemented in the PAL V02.03.01 product, the slope and median relative difference increased to 0.83 ± 0.06 and + 20 %. However, the modifications resulted in larger scatter and the correlation decreased significantly to r=0.72. The results can be improved by not applying a cloud correction for the TROPOMI data in conditions with high aerosol load and when cloud pressures are retrieved close to the surface. The influence of spatially more highly resolved a priori NO 2 vertical profiles and surface reflectivity are investigated using scientific TROPOMI tropospheric NO 2 VCD data products. The comparison of the AirMAP campaign data set to the scientific data products shows that the choice of surface reflectivity database has a minor impact on the tropospheric NO 2 VCD retrieval in the campaign region and season. In comparison, the replacement of the a priori NO 2 profile in combination with the improvements in the retrieval of the PAL V02.03.01 product regarding cloud heights can further increase the tropospheric NO 2 VCDs. This study demonstrates that the underestimation of the TROPOMI tropospheric NO 2 VCD product with respect to the validation data set has been and can be further significantly improved. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
18. Modelling of tropospheric NO₂ using WRF-Chem with optimized temporal NOₓ emission profiles derived from in-situ observations – Comparisons to in-situ, satellite, and MAX-DOAS observations over central Europe.
- Author
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Kuhn, Leon, Beirle, Steffen, Kumar, Vinod, Osipov, Sergey, Pozzer, Andrea, Bösch, Tim, Kumar, Rajesh, and Wagner, Thomas
- Subjects
LIGHT absorption ,SPATIAL resolution ,EARTH stations ,EMISSION inventories ,OPTICAL spectroscopy ,GEOSTATIONARY satellites - Abstract
We present a WRF-Chem simulation over central Europe with a high spatial resolution of 3 km × 3 km and a focus on nitrogen dioxide (NO₂). A regional emission inventory, issued by the German Environmental Agency, with a spatial resolution of 1 km × 1 km is used. We demonstrate, that by precise temporal modulation of the emission data (use of 'temporal profiles'), significant improvement in model accuracy over existing simulations is achieved. Simulated NO₂ surface concentrations are compared to measurements from a total of 275 in-situ measurement stations in Germany, where the model was able to reproduce average noontime NO₂ concentrations with a bias of +0.9 % and R = 0.76. A comparison between modelled NO₂ vertical column densities (VCDs) and satellite observations from TROPOMI (TROPOspheric Monitoring Instrument) is conducted, where crucial aspects of the observation process, such as altitude-dependent NO₂ sensitivity as well as the influence of clouds and a priori assumptions of the retrieval, are taken into account. Simulations and satellite observations are shown to agree with a model bias of −6.6 % and R = 0.84 for monthly means. Lastly, simulated NO₂ concentration profiles are compared to profiles obtained from Multiaxis Differential Optical Absorption Spectroscopy (MAX-DOAS) measurements of five European ground stations using the profile retrieval algorithms from the Mexican MAX-DOAS fit (MMF) and the Mainz Profile Algorithm (MAPA). For stations within Germany, biases of −5.9 % to +50.3 % were obtained when comparing average noontime NO₂ concentrations at different altitudes. Outside of Germany, where lower resolution emission data was used, biases of up to +78.6 % were observed. Overall, the study demonstrates that temporal modulation of emission data is crucial for modelling tropospheric NO₂ realistically. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
19. Investigation of weather conditions and tropospheric BrO transport during Bromine Explosion Events in the Arctic and ozone depletion in Ny-Ålesund observed by satellite and ground-based remote sensing
- Author
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Zilker, Bianca, primary, Blechschmidt, Anne-Marlene, additional, Seo, Sora, additional, Bougoudis, Ilias, additional, Bösch, Tim, additional, Richter, Andreas, additional, and Burrows, John Philip, additional
- Published
- 2022
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20. The Status of the FDR4ATMOS Project
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Lichtenberg, Günter, Slijkhuis, Sander, Hamidouche, Mourad, Coldewey-Egbers, Melanie, Aberle, Bernd, Kumar, Aman, Noël, Stefan, Bramstedt, Klaus, Hilbig, Tina, Bösch, Tim, Lambert, J-C., Van Gent, J., Hubert, Daan, Green, Paul, de Vis, Pieter, Krijger, Matthijs, Dehn, Angelika, and Brizzi, Gabriele
- Subjects
atmosphere trace gases spectral imager calibration - Published
- 2021
21. Investigation of weather conditions and tropospheric BrO transport during Bromine Explosion Events in the Arctic and ozone depletion in Ny-Ålesund observed by satellite and ground-based remote sensing
- Author
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Zilker, Bianca, primary, Blechschmidt, Anne-Marlene, additional, Seo, Sora, additional, Bougoudis, Ilias, additional, Bösch, Tim, additional, Richter, Andreas, additional, and Burrows, John Philip, additional
- Published
- 2021
- Full Text
- View/download PDF
22. Validation of Sentinel-5P TROPOMI tropospheric NO2 products by comparison with NO2 measurements from airborne imaging, ground-based stationary, and mobile car DOAS measurements during the S5P-VAL-DE-Ruhr campaign.
- Author
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Lange, Kezia, Richter, Andreas, Schönhardt, Anja, Meier, Andreas C., Bösch, Tim, Seyler, André, Krause, Kai, Behrens, Lisa K., Wittrock, Folkard, Merlaud, Alexis, Tack, Frederik, Fayt, Caroline, Friedrich, Martina M., Dimitropoulou, Ermioni, Van Roozendael, Michel, Kumar, Vinod, Donner, Sebastian, Dörner, Steffen, Lauster, Bianca, and Razi, Maria
- Subjects
RESEARCH aircraft ,AIRBORNE-based remote sensing ,PEARSON correlation (Statistics) ,AIR pollution ,OPTICAL spectroscopy ,LIGHT absorption ,COLUMNS - Abstract
Airborne imaging differential optical absorption spectroscopy (DOAS), ground-based stationary and car DOAS measurements were conducted during the S5P-VAL-DE-Ruhr campaign in September 2020. The campaign area is located in the Rhine-Ruhr region of North Rhine-Westphalia,Western Germany, which is a pollution hotspot in Europe comprising urban and large industrial emitters. The measurements are used to validate space-borne NO
2 tropospheric vertical column density data products from the Sentinel-5 Precursor (S5P) TROPOspheric Monitoring Instrument (TROPOMI). Seven flights were performed with the airborne imaging DOAS instrument formeasurements of atmospheric pollution (AirMAP), providing measurements which were used to create continuous maps of NO2 in the layer below the aircraft. These flights cover many S5P ground pixels within an area of 30 kmx 35 km and were accompanied by ground-based stationary measurements and three mobile car DOAS instruments. Stationary measurements were conducted by two Pandora, two zenith-sky and two MAX-DOAS instruments distributed over three target areas. Ground-based stationary and car DOAS measurements are used to evaluate the AirMAP tropospheric NO2 vertical column densities and show high Pearson correlation coefficients of 0.87 and 0.89 and slopes of 0.93±0.09 and 0.98±0.02 for the stationary and car DOAS, respectively. Having a spatial resolution of about 100mx 30m, the AirMAP tropospheric NO2 vertical column density (VCD) data creates a link between the ground-based and the TROPOMI measurements with a resolution of 3.5 kmx 5.5 km and is therefore well suited to validate the TROPOMI tropospheric NO2 VCD. The measurements on the seven flight days show strong NO2 variability, which is dependent on the different target areas, the weekday, and the meteorological conditions. The AirMAP campaign dataset is compared to the TROPOMI NO2 operational off-line (OFFL) V01.03.02 data product, the reprocessed NO2 data, using the V02.03.01 of the official L2 processor, provided by the Product Algorithm Laboratory (PAL), and several scientific TROPOMI NO2 data products. The TROPOMI data products and the AirMAP data are highly correlated with correlation coefficients between 0.72 and 0.87, and slopes of 0.38±0.02 to 1.02±0.07. On average, TROPOMI tropospheric NO2 VCDs are lower than the AirMAP NO2 results. The slope increased from 0.38±0.02 for the operational OFFL V01.03.02 product to 0.83±0.06 after the improvements in the retrieval of the PAL V02.03.01 product were implemented. Different auxiliary data, such as spatially higher resolved a priori NO2 vertical profiles, surface reflectivity and the cloud treatment, are investigated using scientific TROPOMI tropospheric NO2 VCD data products to evaluate their impact on the operational TROPOMI NO2 VCD data product. The comparison of the AirMAP campaign dataset to the scientific data products shows that the choice of surface reflectivity data base has a minor impact on the tropospheric NO2 VCD retrieval in the campaign region and season. In comparison, the replacement of the a priori NO2 profile in combination with the improvements in the retrieval of the PAL V02.03.01 product regarding cloud heights has a major impact on the tropospheric NO2 VCD retrieval and increases the slope from 0.88±0.06 to 1.00±0.07. This study demonstrates that the underestimation of the TROPOMI tropospheric NO2 VCD product with respect to the validation dataset has been and can be further significantly improved. [ABSTRACT FROM AUTHOR]- Published
- 2022
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23. Evaluation of UV–visible MAX-DOAS aerosol profiling products by comparison with ceilometer, sun photometer, and in situ observations in Vienna, Austria
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Schreier, Stefan F., primary, Bösch, Tim, additional, Richter, Andreas, additional, Lange, Kezia, additional, Revesz, Michael, additional, Weihs, Philipp, additional, Vrekoussis, Mihalis, additional, and Lotteraner, Christoph, additional
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- 2021
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24. Retrieval of tropospheric BrO columns from TROPOMI and their validation using MAX-DOAS measurements in Ny-Ålesund
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Seo, Sora, primary, Richter, Andreas, additional, Blechschmidt, Anne-M., additional, Bougoudis, Ilias, additional, Wittrock, Folkard, additional, Bösch, Tim, additional, and Burrows, John P., additional
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- 2021
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25. Retrieval and evaluation of tropospheric-aerosol extinction profiles using multi-axis differential optical absorption spectroscopy (MAX-DOAS) measurements over Athens, Greece
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Gratsea, Myrto, primary, Bösch, Tim, additional, Kokkalis, Panagiotis, additional, Richter, Andreas, additional, Vrekoussis, Mihalis, additional, Kazadzis, Stelios, additional, Tsekeri, Alexandra, additional, Papayannis, Alexandros, additional, Mylonaki, Maria, additional, Amiridis, Vassilis, additional, Mihalopoulos, Nikos, additional, and Gerasopoulos, Evangelos, additional
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- 2021
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26. Intercomparison of MAX-DOAS vertical profile retrieval algorithms: studies on field data from the CINDI-2 campaign
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Tirpitz, Jan-Lukas, primary, Frieß, Udo, additional, Hendrick, François, additional, Alberti, Carlos, additional, Allaart, Marc, additional, Apituley, Arnoud, additional, Bais, Alkis, additional, Beirle, Steffen, additional, Berkhout, Stijn, additional, Bognar, Kristof, additional, Bösch, Tim, additional, Bruchkouski, Ilya, additional, Cede, Alexander, additional, Chan, Ka Lok, additional, den Hoed, Mirjam, additional, Donner, Sebastian, additional, Drosoglou, Theano, additional, Fayt, Caroline, additional, Friedrich, Martina M., additional, Frumau, Arnoud, additional, Gast, Lou, additional, Gielen, Clio, additional, Gomez-Martín, Laura, additional, Hao, Nan, additional, Hensen, Arjan, additional, Henzing, Bas, additional, Hermans, Christian, additional, Jin, Junli, additional, Kreher, Karin, additional, Kuhn, Jonas, additional, Lampel, Johannes, additional, Li, Ang, additional, Liu, Cheng, additional, Liu, Haoran, additional, Ma, Jianzhong, additional, Merlaud, Alexis, additional, Peters, Enno, additional, Pinardi, Gaia, additional, Piters, Ankie, additional, Platt, Ulrich, additional, Puentedura, Olga, additional, Richter, Andreas, additional, Schmitt, Stefan, additional, Spinei, Elena, additional, Stein Zweers, Deborah, additional, Strong, Kimberly, additional, Swart, Daan, additional, Tack, Frederik, additional, Tiefengraber, Martin, additional, van der Hoff, René, additional, van Roozendael, Michel, additional, Vlemmix, Tim, additional, Vonk, Jan, additional, Wagner, Thomas, additional, Wang, Yang, additional, Wang, Zhuoru, additional, Wenig, Mark, additional, Wiegner, Matthias, additional, Wittrock, Folkard, additional, Xie, Pinhua, additional, Xing, Chengzhi, additional, Xu, Jin, additional, Yela, Margarita, additional, Zhang, Chengxin, additional, and Zhao, Xiaoyi, additional
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- 2021
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27. Intercomparison of NO2, O4, O3 and HCHO slant column measurements by MAX-DOAS and zenith-sky UV¿visible spectrometers during CINDI-2
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Kreher, Karin, Roozendael, Michel van, Hendrick, Francois, Apituley, Arnoud, Dimitropoulou, Ermioni, Frieß, Udo, Richter, Andreas, Wagner, Thomas, Lampel, Johannes, Abuhassan, Nader, Ang, Li, Anguas, Mónica, Bais, Alkis, Benavent, N., Bösch, Tim, Bognar, Kristof, Borovski, Alexander, Bruchkouski, Ilya, Cede, Alexander, Lok Chan, Ka, Donner, Sebastian, Drosoglou, Theano, Fayt, Caroline, Finkenzeller, Henning, García-Nieto, D., Gielen, Clio, Gómez-Martín, L., Hao, Nan, Henzing, Bas, Herman, Jay R., Hermans, Christian, Hoque, Syedul, Iri, Hitoshi, Jin, Junli, Johnsto, Paul, Khayyam But, Junaid, Khokhar, Fahim, Koenig, T.K., Kuhn, Jonas, Kumar, Vinod, Li, Cheng, Ma, Jianzhong, Merlaud, Alexis, Mishra, A.K., Müller, Moritz, Navarro-Comas, M., Ostendorf, M., Pazmin, Andrea, Peters, Enno, Pinardi, Gaia, Pinharanda, M., Piters, Ankie, Platt, Ulrich, Postylyakov, Oleg, Prados-Roman, C., Puentedura, Olga, Querel, Richard, Saiz-Lopez, A., Schönhardt, A., Schreier, S.F., Seyler, André, Sinha, V., Spinei, Elena, Strong, K., Tack, F., Tian, Xin, Tiefengraber, M., Tirpitz, J.-L., Gent, J. van, Volkamer, R., Vrekoussis, M., Wang, Shanshan, Wang, Zhuoru, Wenig, Mark, Wittrock, F., Xie, P.H., Xu, Jin, Yela, M., Zhang, Chengxin, Zhao, Xiaoyi, Netherlands Space Office, European Space Agency, European Commission, Austrian Science Fund, University of Toronto, Canadian Space Agency, Natural Sciences and Engineering Research Council of Canada, Canada Foundation for Innovation, Consejo Superior de Investigaciones Científicas (España), Ministerio de Economía y Competitividad (España), German Research Foundation, Centre National de la Recherche Scientifique (France), Centre National D'Etudes Spatiales (France), Russian Science Foundation, Russian Foundation for Basic Research, National Aeronautics and Space Administration (US), National Science Foundation (US), University of Bremen, and NASA's Goddard Space Flight Center
- Abstract
40 pags., 22 figs., 13 tabs., In September 2016, 36 spectrometers from 24 institutes measured a number of key atmospheric pollutants for a period of 17¿d during the Second Cabauw Intercomparison campaign for Nitrogen Dioxide measuring Instruments (CINDI-2) that took place at Cabauw, the Netherlands (51.97¿¿N, 4.93¿¿E). We report on the outcome of the formal semi-blind intercomparison exercise, which was held under the umbrella of the Network for the Detection of Atmospheric Composition Change (NDACC) and the European Space Agency (ESA). The three major goals of CINDI-2 were (1) to characterise and better understand the differences between a large number of multi-axis differential optical absorption spectroscopy (MAX-DOAS) and zenith-sky DOAS instruments and analysis methods, (2) to define a robust methodology for performance assessment of all participating instruments, and (3) to contribute to a harmonisation of the measurement settings and retrieval methods. This, in turn, creates the capability to produce consistent high-quality ground-based data sets, which are an essential requirement to generate reliable long-term measurement time series suitable for trend analysis and satellite data validation. The data products investigated during the semi-blind intercomparison are slant columns of nitrogen dioxide (NO2), the oxygen collision complex (O4) and ozone (O3) measured in the UV and visible wavelength region, formaldehyde (HCHO) in the UV spectral region, and NO2 in an additional (smaller) wavelength range in the visible region. The campaign design and implementation processes are discussed in detail including the measurement protocol, calibration procedures and slant column retrieval settings. Strong emphasis was put on the careful alignment and synchronisation of the measurement systems, resulting in a unique set of measurements made under highly comparable air mass conditions. The CINDI-2 data sets were investigated using a regression analysis of the slant columns measured by each instrument and for each of the target data products. The slope and intercept of the regression analysis respectively quantify the mean systematic bias and offset of the individual data sets against the selected reference (which is obtained from the median of either all data sets or a subset), and the rms error provides an estimate of the measurement noise or dispersion. These three criteria are examined and for each of the parameters and each of the data products, performance thresholds are set and applied to all the measurements. The approach presented here has been developed based on heritage from previous intercomparison exercises. It introduces a quantitative assessment of the consistency between all the participating instruments for the MAX-DOAS and zenith-sky DOAS techniques., CINDI-2 received funding from the Netherlands Space Office (NSO). Funding for this study was provided by ESA through the CINDI-2 (ESA contract no. 4000118533/16/ISbo) and FRM4DOAS (ESA contract no. 4000118181/16/I-EF) projects and partly within the EU 7th Framework Programme QA4ECV project (grant agreement no. 607405). The BOKU MAX-DOAS instrument was funded and the participation of Stefan F. Schreier was supported by the Austrian Science Fund (FWF): I 2296-N29. The participation of the University of Toronto team was supported by the Canadian Space Agency (through the AVATARS project) and the Natural Sciences and Engineering Research Council (through the PAHA project). The instrument was primarily funded by the Canada Foundation for Innovation and is usually operated at the Polar Environment Atmospheric Research Laboratory (PEARL) by the Canadian Network for the Detection of Atmospheric Change (CANDAC). Funding for CISC was provided by the UVAS (“Ultraviolet and Visible Atmospheric Sounder”) projects SEOSAT/INGENIO, ESP2015-71299- R, MINECO-FEDER and UE. The activities of the IUP-Heidelberg were supported by the DFG project RAPSODI (grant no. PL 193/17-1). SAOZ and Mini-SAOZ instruments are supported by the Centre National de la Recherche Scientifique (CNRS) and the Centre National d’Etudes Spatiales (CNES). INTA recognises support from the National funding projects HELADO (CTM2013-41311-P) and AVATAR (CGL2014-55230-R). AMOIAP recognises support from the Russian Science Foundation (grant no. 16-17-10275) and the Russian Foundation for Basic Research (grant nos. 16-05- 01062 and 18-35-00682). Ka L. Chan received transnational access funding from ACTRIS-2 (H2020 grant agreement no. 654109). Rainer Volkamer recognises funding from NASA’s Atmospheric Composition Program (NASA-16-NUP2016-0001) and the US National Science Foundation (award AGS-1620530). Henning Finkenzeller is the recipient of a NASA graduate fellowship. Mihalis Vrekoussis recognises support from the University of Bremen and the DFG Research Center/Cluster of Excellence “The Ocean in the Earth System-MARUM”. Financial support through the University of Bremen Institutional Strategy in the framework of the DFG Excellence Initiative is gratefully appreciated for Anja Schönhardt. Pandora instrument deployment was supported by Luftblick through the ESA Pandonia Project and NASA Pandora Project at the Goddard Space Flight Center under NASA Headquarters’ Tropospheric Composition Program. The article processing charges for this open-access publication were covered by BK Scientific.
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- 2020
28. Satellite validation strategy assessments based on the AROMAT campaigns
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Merlaud, Alexis, primary, Belegante, Livio, additional, Constantin, Daniel-Eduard, additional, Den Hoed, Mirjam, additional, Meier, Andreas Carlos, additional, Allaart, Marc, additional, Ardelean, Magdalena, additional, Arseni, Maxim, additional, Bösch, Tim, additional, Brenot, Hugues, additional, Calcan, Andreea, additional, Dekemper, Emmanuel, additional, Donner, Sebastian, additional, Dörner, Steffen, additional, Balanica Dragomir, Mariana Carmelia, additional, Georgescu, Lucian, additional, Nemuc, Anca, additional, Nicolae, Doina, additional, Pinardi, Gaia, additional, Richter, Andreas, additional, Rosu, Adrian, additional, Ruhtz, Thomas, additional, Schönhardt, Anja, additional, Schuettemeyer, Dirk, additional, Shaiganfar, Reza, additional, Stebel, Kerstin, additional, Tack, Frederik, additional, Nicolae Vâjâiac, Sorin, additional, Vasilescu, Jeni, additional, Vanhamel, Jurgen, additional, Wagner, Thomas, additional, and Van Roozendael, Michel, additional
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- 2020
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29. Intercomparison of NO<sub>2</sub>, O<sub>4</sub>, O<sub>3</sub> and HCHO slant column measurements by MAX-DOAS and zenith-sky UV–visible spectrometers during CINDI-2
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Kreher, Karin, primary, Van Roozendael, Michel, additional, Hendrick, Francois, additional, Apituley, Arnoud, additional, Dimitropoulou, Ermioni, additional, Frieß, Udo, additional, Richter, Andreas, additional, Wagner, Thomas, additional, Lampel, Johannes, additional, Abuhassan, Nader, additional, Ang, Li, additional, Anguas, Monica, additional, Bais, Alkis, additional, Benavent, Nuria, additional, Bösch, Tim, additional, Bognar, Kristof, additional, Borovski, Alexander, additional, Bruchkouski, Ilya, additional, Cede, Alexander, additional, Chan, Ka Lok, additional, Donner, Sebastian, additional, Drosoglou, Theano, additional, Fayt, Caroline, additional, Finkenzeller, Henning, additional, Garcia-Nieto, David, additional, Gielen, Clio, additional, Gómez-Martín, Laura, additional, Hao, Nan, additional, Henzing, Bas, additional, Herman, Jay R., additional, Hermans, Christian, additional, Hoque, Syedul, additional, Irie, Hitoshi, additional, Jin, Junli, additional, Johnston, Paul, additional, Khayyam Butt, Junaid, additional, Khokhar, Fahim, additional, Koenig, Theodore K., additional, Kuhn, Jonas, additional, Kumar, Vinod, additional, Liu, Cheng, additional, Ma, Jianzhong, additional, Merlaud, Alexis, additional, Mishra, Abhishek K., additional, Müller, Moritz, additional, Navarro-Comas, Monica, additional, Ostendorf, Mareike, additional, Pazmino, Andrea, additional, Peters, Enno, additional, Pinardi, Gaia, additional, Pinharanda, Manuel, additional, Piters, Ankie, additional, Platt, Ulrich, additional, Postylyakov, Oleg, additional, Prados-Roman, Cristina, additional, Puentedura, Olga, additional, Querel, Richard, additional, Saiz-Lopez, Alfonso, additional, Schönhardt, Anja, additional, Schreier, Stefan F., additional, Seyler, André, additional, Sinha, Vinayak, additional, Spinei, Elena, additional, Strong, Kimberly, additional, Tack, Frederik, additional, Tian, Xin, additional, Tiefengraber, Martin, additional, Tirpitz, Jan-Lukas, additional, van Gent, Jeroen, additional, Volkamer, Rainer, additional, Vrekoussis, Mihalis, additional, Wang, Shanshan, additional, Wang, Zhuoru, additional, Wenig, Mark, additional, Wittrock, Folkard, additional, Xie, Pinhua H., additional, Xu, Jin, additional, Yela, Margarita, additional, Zhang, Chengxin, additional, and Zhao, Xiaoyi, additional
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- 2020
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30. Retrieval and evaluation of tropospheric aerosol extinction profiles using MAX-DOAS measurements over Athens, Greece
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Gratsea, Myrto, primary, Bösch, Tim, additional, Kokkalis, Panos, additional, Richter, Andreas, additional, Vrekoussis, Mihalis, additional, Kazadzis, Stelios, additional, Tsekeri, Alexandra, additional, Papayannis, Alexandros, additional, Mylonaki, Maria, additional, Amiridis, Vassilis, additional, Mihalopoulos, Nikos, additional, and Gerasopoulos, Evangelos, additional
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- 2020
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31. A method for retrieving the spatial distribution of trace gases using measurements of three ground-based MAX-DOAS instruments
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Revesz, Michael, primary, Schreier, Stefan F., additional, Weihs, Philipp, additional, Bösch, Tim, additional, Lange, Kezia, additional, Richter, Andreas, additional, Vrekoussis, Mihalis, additional, and Schmalwieser, Alois W., additional
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- 2020
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32. The FDR4ATMOS Project
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Lichtenberg, Günter, primary, Slijkhuis, Sander, additional, Hamidouche, Mourad, additional, Coldewey-Egbers, Melanie, additional, Aberle, Bernd, additional, Noël, Stefan, additional, Bramstedt, Klaus, additional, Hilbig, Tina, additional, Bösch, Tim, additional, Lambert, Jean-Christopher, additional, van Gent, Jeroen, additional, Hubert, Daan, additional, Green, Paul, additional, Hunt, Sam, additional, Krijger, Matthijs, additional, Dehn, Angelika, additional, and Brizzi, Gabriele, additional
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- 2020
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33. ESA FRM4DOAS: Towards the launch of the NDACC MAX-DOAS Central Processing Service
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Hendrick, Francois, primary, Fayt, Caroline, additional, Friedrich, Martina M., additional, Beirle, Steffen, additional, Frieẞ, Udo, additional, Richter, Andreas, additional, Bösch, Tim, additional, Kreher, Karin, additional, Piters, Ankie, additional, Wagner, Thomas, additional, Tirpitz, Jan-Lukas, additional, Bais, Alkis, additional, Prados Roman, Cristina, additional, Puentedura, Olga, additional, Cede, Alexander, additional, Lind, Elena, additional, Dehn, Angelika, additional, von Bismarck, Jonas, additional, Casadio, Stefano, additional, and Van Roozendael, Michel, additional
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- 2020
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34. Spatial and temporal distributions of NO2 and aerosols over the urban environment of Vienna during the VINDOBONA project (2017-2019)
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Schreier, Stefan, primary, Richter, Andreas, additional, Bösch, Tim, additional, Lange, Kezia, additional, Revesz, Michael, additional, Hilboll, Andreas, additional, Peters, Enno, additional, Vrekoussis, Mihalis, additional, Weihs, Philipp, additional, Schmalwieser, Alois, additional, and Burrows, John, additional
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- 2020
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35. Evaluating different methods for elevation calibration of MAX-DOAS (Multi AXis Differential Optical Absorption Spectroscopy) instruments during the CINDI-2 campaign
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Donner, Sebastian, primary, Kuhn, Jonas, additional, Van Roozendael, Michel, additional, Bais, Alkiviadis, additional, Beirle, Steffen, additional, Bösch, Tim, additional, Bognar, Kristof, additional, Bruchkouski, Ilya, additional, Chan, Ka Lok, additional, Dörner, Steffen, additional, Drosoglou, Theano, additional, Fayt, Caroline, additional, Frieß, Udo, additional, Hendrick, François, additional, Hermans, Christian, additional, Jin, Junli, additional, Li, Ang, additional, Ma, Jianzhong, additional, Peters, Enno, additional, Pinardi, Gaia, additional, Richter, Andreas, additional, Schreier, Stefan F., additional, Seyler, André, additional, Strong, Kimberly, additional, Tirpitz, Jan-Lukas, additional, Wang, Yang, additional, Xie, Pinhua, additional, Xu, Jin, additional, Zhao, Xiaoyi, additional, and Wagner, Thomas, additional
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- 2020
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36. The Airborne ROmanian Measurements of Aerosols and Trace gases (AROMAT) campaigns
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Merlaud, Alexis, primary, Belegante, Livio, additional, Constantin, Daniel-Eduard, additional, Den Hoed, Mirjam, additional, Meier, Andreas Carlos, additional, Allaart, Marc, additional, Ardelean, Magdalena, additional, Arseni, Maxim, additional, Bösch, Tim, additional, Brenot, Hugues, additional, Calcan, Andreea, additional, Dekemper, Emmanuel, additional, Donner, Sebastian, additional, Dörner, Steffen, additional, Dragomir, Carmelia, additional, Georgescu, Lucian, additional, Nemuc, Anca, additional, Nicolae, Doina, additional, Pinardi, Gaia, additional, Richter, Andreas, additional, Rosu, Adrian, additional, Ruhtz, Thomas, additional, Schönhardt, Anja, additional, Schuettemeyer, Dirk, additional, Shaiganfar, Reza, additional, Stebel, Kerstin, additional, Tack, Frederik, additional, Nicolae Vâjâiac, Sorin, additional, Vasilescu, Jeni, additional, Vanhamel, Jurgen, additional, Wagner, Thomas, additional, and Van Roozendael, Michel, additional
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- 2020
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37. Supplementary material to "The Airborne ROmanian Measurements of Aerosols and Trace gases (AROMAT) campaigns"
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Merlaud, Alexis, primary, Belegante, Livio, additional, Constantin, Daniel-Eduard, additional, Den Hoed, Mirjam, additional, Meier, Andreas Carlos, additional, Allaart, Marc, additional, Ardelean, Magdalena, additional, Arseni, Maxim, additional, Bösch, Tim, additional, Brenot, Hugues, additional, Calcan, Andreea, additional, Dekemper, Emmanuel, additional, Donner, Sebastian, additional, Dörner, Steffen, additional, Dragomir, Carmelia, additional, Georgescu, Lucian, additional, Nemuc, Anca, additional, Nicolae, Doina, additional, Pinardi, Gaia, additional, Richter, Andreas, additional, Rosu, Adrian, additional, Ruhtz, Thomas, additional, Schönhardt, Anja, additional, Schuettemeyer, Dirk, additional, Shaiganfar, Reza, additional, Stebel, Kerstin, additional, Tack, Frederik, additional, Nicolae Vâjâiac, Sorin, additional, Vasilescu, Jeni, additional, Vanhamel, Jurgen, additional, Wagner, Thomas, additional, and Van Roozendael, Michel, additional
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- 2020
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38. Intercomparison of MAX-DOAS vertical profile retrieval algorithms: studies on field data from the CINDI-2 campaign
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Tirpitz, Jan-Lukas, primary, Frieß, Udo, additional, Hendrick, François, additional, Alberti, Carlos, additional, Allaart, Marc, additional, Apituley, Arnoud, additional, Bais, Alkis, additional, Beirle, Steffen, additional, Berkhout, Stijn, additional, Bognar, Kristof, additional, Bösch, Tim, additional, Bruchkouski, Ilya, additional, Cede, Alexander, additional, Chan, Ka Lok, additional, den Hoed, Mirjam, additional, Donner, Sebastian, additional, Drosoglou, Theano, additional, Fayt, Caroline, additional, Friedrich, Martina M., additional, Frumau, Arnoud, additional, Gast, Lou, additional, Gielen, Clio, additional, Gomez-Martín, Laura, additional, Hao, Nan, additional, Hensen, Arjen, additional, Henzing, Bas, additional, Hermans, Christian, additional, Jin, Junli, additional, Kreher, Karin, additional, Kuhn, Jonas, additional, Lampel, Johannes, additional, Li, Ang, additional, Liu, Cheng, additional, Liu, Haoran, additional, Ma, Jianzhong, additional, Merlaud, Alexis, additional, Peters, Enno, additional, Pinardi, Gaia, additional, Piters, Ankie, additional, Platt, Ulrich, additional, Puentedura, Olga, additional, Richter, Andreas, additional, Schmitt, Stefan, additional, Spinei, Elena, additional, Stein Zweers, Deborah, additional, Strong, Kimberly, additional, Swart, Daan, additional, Tack, Frederick, additional, Tiefengraber, Martin, additional, van der Hoff, René, additional, van Roozendael, Michel, additional, Vlemmix, Tim, additional, Vonk, Jan, additional, Wagner, Thomas, additional, Wang, Yang, additional, Wang, Zhuoru, additional, Wenig, Mark, additional, Wiegner, Matthias, additional, Wittrock, Folkard, additional, Xie, Pinhua, additional, Xing, Chengzhi, additional, Xu, Jin, additional, Yela, Margarita, additional, Zhang, Chengxin, additional, and Zhao, Xiaoyi, additional
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- 2020
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39. Supplementary material to "Intercomparison of MAX-DOAS vertical profile retrieval algorithms: studies on field data from the CINDI-2 campaign"
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Tirpitz, Jan-Lukas, primary, Frieß, Udo, additional, Hendrick, François, additional, Alberti, Carlos, additional, Allaart, Marc, additional, Apituley, Arnoud, additional, Bais, Alkis, additional, Beirle, Steffen, additional, Berkhout, Stijn, additional, Bognar, Kristof, additional, Bösch, Tim, additional, Bruchkouski, Ilya, additional, Cede, Alexander, additional, Chan, Ka Lok, additional, den Hoed, Mirjam, additional, Donner, Sebastian, additional, Drosoglou, Theano, additional, Fayt, Caroline, additional, Friedrich, Martina M., additional, Frumau, Arnoud, additional, Gast, Lou, additional, Gielen, Clio, additional, Gomez-Martín, Laura, additional, Hao, Nan, additional, Hensen, Arjen, additional, Henzing, Bas, additional, Hermans, Christian, additional, Jin, Junli, additional, Kreher, Karin, additional, Kuhn, Jonas, additional, Lampel, Johannes, additional, Li, Ang, additional, Liu, Cheng, additional, Liu, Haoran, additional, Ma, Jianzhong, additional, Merlaud, Alexis, additional, Peters, Enno, additional, Pinardi, Gaia, additional, Piters, Ankie, additional, Platt, Ulrich, additional, Puentedura, Olga, additional, Richter, Andreas, additional, Schmitt, Stefan, additional, Spinei, Elena, additional, Stein Zweers, Deborah, additional, Strong, Kimberly, additional, Swart, Daan, additional, Tack, Frederick, additional, Tiefengraber, Martin, additional, van der Hoff, René, additional, van Roozendael, Michel, additional, Vlemmix, Tim, additional, Vonk, Jan, additional, Wagner, Thomas, additional, Wang, Yang, additional, Wang, Zhuoru, additional, Wenig, Mark, additional, Wiegner, Matthias, additional, Wittrock, Folkard, additional, Xie, Pinhua, additional, Xing, Chengzhi, additional, Xu, Jin, additional, Yela, Margarita, additional, Zhang, Chengxin, additional, and Zhao, Xiaoyi, additional
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- 2020
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40. High-resolution airborne imaging DOAS measurements of NO2 above Bucharest during AROMAT
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Meier, Andreas Carlos, Schönhardt, Anja, Bösch, Tim, Richter, Andreas, Seyler, André, Ruhtz, Thomas, Constantin, Daniel-Eduard, Shaiganfar, Reza, Wagner, Thomas, Merlaud, Alexis, Roozendael, Michel, Belegante, Livio, Nicolae, Doina, Georgescu, Lucian, and Burrows, John Philip
- Subjects
lcsh:TA715-787 ,lcsh:Earthwork. Foundations ,lcsh:TA170-171 ,lcsh:Environmental engineering - 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 of Aerosols and Trace gases) in September 2014. These measurements were performed with the Airborne imaging Differential Optical Absorption Spectroscopy (DOAS) instrument for Measurements of Atmospheric Pollution (AirMAP) and provide nearly gapless maps of column densities of NO2 below the aircraft with a high spatial resolution of better than 100 m. The air mass factors, which are needed to convert the measured differential slant column densities (dSCDs) to vertical column densities (VCDs), have a strong dependence on the surface reflectance, which has to be accounted for in the retrieval. This is especially important for measurements above urban areas, where the surface properties vary strongly. As the instrument is not radiometrically calibrated, we have developed a method to derive the surface reflectance from intensities measured by AirMAP. This method is based on radiative transfer calculation with SCIATRAN and a reference area for which the surface reflectance is known. While surface properties are clearly apparent in the NO2 dSCD results, this effect is successfully corrected for in the VCD results. Furthermore, we investigate the influence of aerosols on the retrieval for a variety of aerosol profiles that were measured in the context of the AROMAT campaigns. The results of two research flights are presented, which reveal distinct horizontal distribution patterns and strong spatial gradients of NO2 across the city. Pollution levels range from background values in the outskirts located upwind of the city to about 4 × 1016 molec cm−2 in the polluted city center. Validation against two co-located mobile car-DOAS measurements yields good agreement between the datasets, with correlation coefficients of R = 0.94 and R = 0.85, respectively. Estimations on the NOx emission rate of Bucharest for the two flights yield emission rates of 15.1 ± 9.4 and 13.6 ± 8.4 mol s−1, respectively.
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- 2017
41. Intercomparison of NO2, O4, O3 and HCHO slant column measurements by MAX-DOAS and zenith-sky UV-Visible spectrometers during the CINDI-2 campaign
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Kreher, Karin, Roozendael, Michel, Hendrick, Francois, Apituley, Arnoud, Dimitropoulou, Ermioni, Frieß, Udo, Richter, Andreas, Wagner, Thomas, Abuhassan, Nader, Ang, Li, Anguas, Monica, Bais, Alkis, Benavent, Nuria, Bösch, Tim, Bognar, Kristof, Borovski, Alexander, Bruchkouski, Ilya, Cede, Alexander, Chan, Ka L., Donner, Sebastian, Drosoglou, Theano, Fayt, Caroline, Finkenzeller, Henning, Garcia-Nieto, David, Gielen, Clio, Gómez-Martín, Laura, Hao, Nan, Herman, Jay R., Hermans, Christian, Hoque, Syedul, Irie, Hitoshi, Jin, Junli, Johnston, Paul, Khayyam Butt, Junaid, Khokhar, Fahim, Koenig, Theodore K., Kuhn, Jonas, Kumar, Vinod, Lampel, Johannes, Liu, Cheng, Ma, Jianzhong, Merlaud, Alexis, Mishra, Abhishek K., Müller, Moritz, Navarro-Comas, Monica, Ostendorf, Mareike, Pazmino, Andrea, Peters, Enno, Pinardi, Gaia, Pinharanda, Manuel, Piters, Ankie, Platt, Ulrich, Postylyakov, Oleg, Prados-Roman, Cristina, Puentedura, Olga, Querel, Richard, Saiz-Lopez, Alfonso, Schönhardt, Anja, Schreier, Stefan F., Seyler, Andre, Sinha, Vinayak, Spinei, Elena, Strong, Kimberly, Tack, Frederik, Tian, Xin, Tiefengraber, Martin, Tirpitz, Jan-Lukas, Gent, Jeron, Volkamer, Rainer, Vrekoussis, Mihalis, Wang, Shanshan, Wang, Zhuoru, Wenig, Mark, Wittrock, Folkard, Xie, Pinhua H., Xu, Jin, Yela, Margarita, Zhang, Chengxin, and Zhao, Xiaoyi
- Abstract
In September 2016, 36 spectrometers from 24 institutes measured a number of key atmospheric pollutants for a period of 17 days during the Second Cabauw Intercomparison campaign for Nitrogen Dioxide measuring Instruments (CINDI-2) that took place at Cabauw, The Netherlands (51.97° N, 4.93° E). We report on the outcome of the formal semi-blind intercomparison exercise, which was held under the umbrella of the Network for the Detection of Atmospheric Composition Change (NDACC) and the European Space Agency (ESA). The three major goals of CINDI-2 were to characterise and better understand the differences between a large number of Multi-AXis Differential Optical Absorption Spectroscopy (MAX-DOAS) and zenith-sky DOAS instruments and analysis methods, to discuss the performance of the various types of instruments and to contribute to a harmonisation of the measurement settings and retrieval methods. This, in turn, creates the capability to produce consistent high-quality ground-based data sets, which are an essential requirement to generate reliable long-term measurement time series suitable for trend analysis and satellite data validation. The data products investigated during the semi-blind intercomparison are slant columns of nitrogen dioxide (NO2), the oxygen dimer (O4) and ozone (O3) measured in the UV and visible wavelength region, formaldehyde (HCHO) in the UV spectral region and NO2 in an additional (smaller) wavelength range in the visible. The campaign design and implementation processes are discussed in detail including the measurement protocol, calibration procedures and slant column retrieval settings. Strong emphasis was put on the careful alignment and synchronisation of the measurement systems, resulting in an unprecedented set of measurements made under highly comparable air mass conditions. The CINDI-2 data sets were investigated using a regression analysis of the slant columns measured by each instrument and for each of the target data products. The slope and intercept of the regression analysis respectively quantify the mean systematic bias and offset of the individual data sets against the reference, and the RMS error provides an estimate of the measurement noise or dispersion. These three criteria are examined and for each of the parameters and each of the data products, performance thresholds are set and applied to all the measurements. The approach presented here has been developed based on heritage from previous intercomparison exercises. It introduces a quantitative assessment of the measurement performance of all the participating instruments for the MAX-DOAS and zenith-sky DOAS techniques.
- Published
- 2019
42. Is a scaling factor required to obtain closure between measured and modelled atmospheric O₄ absorptions? An assessment of uncertainties of measurements and radiative transfer simulations for 2 selected days during the MAD-CAT campaign
- Author
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Wagner, Thomas, Beirle, Steffen, Benavent, Nuria, Bösch, Tim, Chan, Ka Lok, Donner, Sebastian, Dörner, Steffen, Fayt, Caroline, Friess, Udo, Garcia-Nieto, David, Gielen, Clio, González-Bartolome, David, Gomez, Laura, Hendrick, Francoise, Henzing, Bas, Jin, Jun Li, Lampel, Johannes, Ma, Jianzhong, Mies, Kornelia, Navarro, Mónica, Peters, Enno, Pinardi, Gaia, Puentedura, Olga, Puķīte, Janis, Remmers, Julia, Richter, Andreas, Saiz-Lopez, Alfonso, Shaiganfar, Reza, Sihler, Holger, Van Roozendael, Michel, Wang, Yang, and Yela, Margarita
- Subjects
MAX-DOAS ,O4 ,Atmosphärenprozessoren - Abstract
In this study the consistency between MAX-DOAS measurements and radiative transfer simulations of the atmospheric O4 absorption is investigated on 2 mainly cloud-free days during the MAD-CAT campaign in Mainz, Germany, in summer 2013. In recent years several studies indicated that measurements and radiative transfer simulations of the atmospheric O4 absorption can only be brought into agreement if a so-called scaling factor (
- Published
- 2019
43. Detailierte Analyse von MAX-DOAS Messungen in Bremen : räumliche und zeitliche Verteilung von Aerosolen, Formaldehyd und Stickstoffdioxid
- Author
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Bösch, Tim, Burrows, John P., Richter, Andreas, and Wagner, Thomas
- Subjects
Vertical column density ,Profile retrieval ,Slant column density ,530 Physics ,Formaldehyde ,Nitrogen Dioxide ,ddc:530 ,MAX-DOAS ,Onion peeling ,BOREAS ,Aerosol - Abstract
In this thesis, spatial and temporal tropospheric inhomogeneities in the distribution of nitrogen dioxide (NO2), formaldehyde (HCHO) and aerosols are investigated. The analysis was done on a three years dataset (2015 - 2017) of ground-based multi-axis differential optical absorption spectroscopy (MAX-DOAS) measurements in Bremen. MAX-DOAS measurements were investigated in three different azimuthal viewing directions in order to analyse lateral changes in the distribution of NO2 and HCHO in Bremen. A clear seasonality was found and explained by anthropogenic and biogenic emissions for NO2 and HCHO, respectively. While no significant azimuthal variability for HCHO was found, NO2 differs strongly for the westerly and southerly directions due to lateral inhomogeneities and a more frequent pointing towards the sun which has a strong impact on the results. In order to localize possible dominant emission sources of NO2 within the area of Bremen, the onion peeling approach was successfully applied by usage of the three fitting windows in the ultra-violet (UV) and visible (vis) spectral range. Strong emitters could be identified having a large impact on average NO2 results. A major challenge for the analysis of trace gases in the troposphere is the usually insufficient knowledge of aerosols, which might have a large impact on spectroscopic measurements. The novel MAX-DOAS profiling algorithm BOREAS was developed and its accuracy is validated with the help of synthetic data as well as ancillary measurements of the CINDI-2 field campaign (Cabauw, the Netherlands, 2016). In contrast to other algorithms, BOREASa aerosol information are retrieved by minimizing the difference of O4 optical depths of measurements and forward modelling calculations. The resulting aerosol extinction coefficient profiles were used for the retrieval of vertical trace gas concentration profiles. In this thesis, several retrieval modes and various ways of improving the regularization between measurement and a priori constraints as well as the selection of proper a priori profiles by use of a priori pre-scaling were investigated. The BOREAS algorithm was finally applied to the full MAX-DOAS dataset, and three years of aerosol and trace gas vertical profiles from the measurement location Bremen are presented and discussed with the help of in-situ as well as AERONET measurements. Seasonal, weekday and diurnal cycles for aerosols and NO2 were found which could be attributed to near surface emissions mainly from traffic and power plants. The seasonal cycle of HCHO is found to be dominated by biogenic emissions in summer, in addition to a smaller fraction of anthropogenic emissions in winter. While NO2 and aerosols are mainly focussed in layers close to the surface, larger HCHO concentrations could also be observed in the complete planetary boundary layer showing the need for the analysis of vertical concentration profiles of trace gases in the troposphere.
- Published
- 2019
44. Is a scaling factor required to obtain closure between measured and modelled atmospheric O4 absorptions? – A case study for two days during the MADCAT campaign
- Author
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Wagner, Thomas, Beirle, Steffen, Benavent, Nuria, Bösch, Tim, Chan, Kai Lok, Donner, Sebastian, Dörner, Steffen, Fayt, Caroline, Frieß, Udo, García-Nieto, David, Gielen, Clio, González-Bartolome, David, Gomez, Laura, Hendrick, François, Henzing, Bas, Jin, Jun Li, Lampel, Johannes, Ma, Jianzhong, Mies, Kornelia, Navarro, Mónica, Peters, Enno, Pinardi, Gaia, Puentedura, Olga, Puķīte, Janis, Remmers, Julia, Richter, Andreas, Saiz-Lopez, Alfonso, Shaiganfar, Reza, Sihler, Holger, Roozendael, Michel, Wang, Yang, and Yela, Margarita
- Abstract
In this study the consistency between MAX-DOAS measurements and radiative transfer simulations of the atmospheric O4 absorption is investigated on two mainly clear days during the MAD-CAT campaign in Mainz, Germany, in Summer 2013. In recent years several studies indicated that measurements and radiative transfer simulations of the atmospheric O4 absorption can only be brought into agreement if a so-called scaling factor (4 absorption. However, many studies, in particular based on direct sun light measurements, came to the opposite conclusion, that there is no need for a scaling factor. Up to now, there is no explanation for the observed discrepancies between measurements and simulations. Previous studies infered the need for a scaling factor from the comparison of the aerosol optical depth derived from MAX-DOAS O4 measurements with that derived from coincident sun photometer measurements. In this study a different approach is chosen: the measured O4 absorption at 360 nm is directly compared to the O4 absorption obtained from radiative transfer simulations. The atmospheric conditions used as input for the radiative transfer simulations were taken from independent data sets, in particular from sun photometer and ceilometer measurements at the measurement site. The comparisons are performed for two selected clear days with similar aerosol optical depth but very different aerosol properties. For both days not only the O4 absorptions are compared, but also all relevant error sources of the spectral analysis, the radiative transfer simulations as well as the extraction of the input parameters used for the radiative transfer simulations are quantified. One important result obtained from the analysis of synthetic spectra is that the O4 absorptions derived from the spectral analysis agree within 1 % with the corresponding radiative transfer simulations. The performed tests and sensitivity studies might be useful for the analysis and interpretation of O4 MAX-DOAS measurements in future studies. Different comparison results are found for both days: On 18 June, measurements and simulations agree within their (rather large) errors (the ratio of simulated and measured O4 absorptions is found to be 1.01 ± 0.16). In contrast, on 8 July measurements and simulations significantly disagree: For the middle period of that day the ratio of simulated and measured O4 absorptions is found to be 0.71 ± 0.12, which differs significantly from unity. Thus for that day a scaling factor is needed to bring measurements and simulations into agreement. One possible reason for the comparison results on 18 June is the rather large aerosol extinction (and its large uncertainty) close to the surface, which has a large effect on the radiative transfer simulations. Besides the inconsistent comparison results for both days, also no explanation for a O4 scaling factor could be derived in this study. Thus similar, but more extended future studies should be performed, which preferably include more measurement days, more instruments and should be supported by more detailed independent aerosol measurements. Also additional wavelengths should be included. The MAX-DOAS measurements collected during the recent CINDI-2 campaign are probably well suited for that purpose.
- Published
- 2018
45. Full-azimuthal imaging-DOAS observations of NO2 and O4 during CINDI-2
- Author
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Peters, Enno, primary, Ostendorf, Mareike, additional, Bösch, Tim, additional, Seyler, André, additional, Schönhardt, Anja, additional, Schreier, Stefan F., additional, Henzing, Jeroen Sebastiaan, additional, Wittrock, Folkard, additional, Richter, Andreas, additional, Vrekoussis, Mihalis, additional, and Burrows, John P., additional
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- 2019
- Full Text
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46. Evaluating different methods for elevation calibration of MAX-DOAS instruments during the CINDI-2 campaign
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Donner, Sebastian, primary, Kuhn, Jonas, additional, Van Roozendael, Michel, additional, Bais, Alkiviadis, additional, Beirle, Steffen, additional, Bösch, Tim, additional, Bognar, Kristof, additional, Bruchkousky, Ilya, additional, Chan, Ka Lok, additional, Drosoglou, Theano, additional, Fayt, Caroline, additional, Frieß, Udo, additional, Hendrick, François, additional, Hermans, Christian, additional, Jin, Junli, additional, Li, Ang, additional, Ma, Jianzhong, additional, Peters, Enno, additional, Pinardi, Gaia, additional, Richter, Andreas, additional, Schreier, Stefan F., additional, Seyler, André, additional, Strong, Kimberly, additional, Tirpitz, Jan-Lukas, additional, Wang, Yang, additional, Xie, Pinhua, additional, Xu, Jin, additional, Zhao, Xiaoyi, additional, and Wagner, Thomas, additional
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- 2019
- Full Text
- View/download PDF
47. Intercomparison of NO2, O4, O3 and HCHO slant column measurements by MAX-DOAS and zenith-sky UV-Visible spectrometers during the CINDI-2 campaign
- Author
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Kreher, Karin, primary, Van Roozendael, Michel, additional, Hendrick, Francois, additional, Apituley, Arnoud, additional, Dimitropoulou, Ermioni, additional, Frieß, Udo, additional, Richter, Andreas, additional, Wagner, Thomas, additional, Abuhassan, Nader, additional, Ang, Li, additional, Anguas, Monica, additional, Bais, Alkis, additional, Benavent, Nuria, additional, Bösch, Tim, additional, Bognar, Kristof, additional, Borovski, Alexander, additional, Bruchkouski, Ilya, additional, Cede, Alexander, additional, Chan, Ka L., additional, Donner, Sebastian, additional, Drosoglou, Theano, additional, Fayt, Caroline, additional, Finkenzeller, Henning, additional, Garcia-Nieto, David, additional, Gielen, Clio, additional, Gómez-Martín, Laura, additional, Hao, Nan, additional, Herman, Jay R., additional, Hermans, Christian, additional, Hoque, Syedul, additional, Irie, Hitoshi, additional, Jin, Junli, additional, Johnston, Paul, additional, Khayyam Butt, Junaid, additional, Khokhar, Fahim, additional, Koenig, Theodore K., additional, Kuhn, Jonas, additional, Kumar, Vinod, additional, Lampel, Johannes, additional, Liu, Cheng, additional, Ma, Jianzhong, additional, Merlaud, Alexis, additional, Mishra, Abhishek K., additional, Müller, Moritz, additional, Navarro-Comas, Monica, additional, Ostendorf, Mareike, additional, Pazmino, Andrea, additional, Peters, Enno, additional, Pinardi, Gaia, additional, Pinharanda, Manuel, additional, Piters, Ankie, additional, Platt, Ulrich, additional, Postylyakov, Oleg, additional, Prados-Roman, Cristina, additional, Puentedura, Olga, additional, Querel, Richard, additional, Saiz-Lopez, Alfonso, additional, Schönhardt, Anja, additional, Schreier, Stefan F., additional, Seyler, Andre, additional, Sinha, Vinayak, additional, Spinei, Elena, additional, Strong, Kimberly, additional, Tack, Frederik, additional, Tian, Xin, additional, Tiefengraber, Martin, additional, Tirpitz, Jan-Lukas, additional, van Gent, Jeron, additional, Volkamer, Rainer, additional, Vrekoussis, Mihalis, additional, Wang, Shanshan, additional, Wang, Zhuoru, additional, Wenig, Mark, additional, Wittrock, Folkard, additional, Xie, Pinhua H., additional, Xu, Jin, additional, Yela, Margarita, additional, Zhang, Chengxin, additional, and Zhao, Xiaoyi, additional
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- 2019
- Full Text
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48. Supplementary material to "Intercomparison of NO2, O4, O3 and HCHO slant column measurements by MAX-DOAS and zenith-sky UV-Visible spectrometers during the CINDI-2 campaign"
- Author
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Kreher, Karin, primary, Van Roozendael, Michel, additional, Hendrick, Francois, additional, Apituley, Arnoud, additional, Dimitropoulou, Ermioni, additional, Frieß, Udo, additional, Richter, Andreas, additional, Wagner, Thomas, additional, Abuhassan, Nader, additional, Ang, Li, additional, Anguas, Monica, additional, Bais, Alkis, additional, Benavent, Nuria, additional, Bösch, Tim, additional, Bognar, Kristof, additional, Borovski, Alexander, additional, Bruchkouski, Ilya, additional, Cede, Alexander, additional, Chan, Ka L., additional, Donner, Sebastian, additional, Drosoglou, Theano, additional, Fayt, Caroline, additional, Finkenzeller, Henning, additional, Garcia-Nieto, David, additional, Gielen, Clio, additional, Gómez-Martín, Laura, additional, Hao, Nan, additional, Herman, Jay R., additional, Hermans, Christian, additional, Hoque, Syedul, additional, Irie, Hitoshi, additional, Jin, Junli, additional, Johnston, Paul, additional, Khayyam Butt, Junaid, additional, Khokhar, Fahim, additional, Koenig, Theodore K., additional, Kuhn, Jonas, additional, Kumar, Vinod, additional, Lampel, Johannes, additional, Liu, Cheng, additional, Ma, Jianzhong, additional, Merlaud, Alexis, additional, Mishra, Abhishek K., additional, Müller, Moritz, additional, Navarro-Comas, Monica, additional, Ostendorf, Mareike, additional, Pazmino, Andrea, additional, Peters, Enno, additional, Pinardi, Gaia, additional, Pinharanda, Manuel, additional, Piters, Ankie, additional, Platt, Ulrich, additional, Postylyakov, Oleg, additional, Prados-Roman, Cristina, additional, Puentedura, Olga, additional, Querel, Richard, additional, Saiz-Lopez, Alfonso, additional, Schönhardt, Anja, additional, Schreier, Stefan F., additional, Seyler, Andre, additional, Sinha, Vinayak, additional, Spinei, Elena, additional, Strong, Kimberly, additional, Tack, Frederik, additional, Tian, Xin, additional, Tiefengraber, Martin, additional, Tirpitz, Jan-Lukas, additional, van Gent, Jeron, additional, Volkamer, Rainer, additional, Vrekoussis, Mihalis, additional, Wang, Shanshan, additional, Wang, Zhuoru, additional, Wenig, Mark, additional, Wittrock, Folkard, additional, Xie, Pinhua H., additional, Xu, Jin, additional, Yela, Margarita, additional, Zhang, Chengxin, additional, and Zhao, Xiaoyi, additional
- Published
- 2019
- Full Text
- View/download PDF
49. Is a scaling factor required to obtain closure between measured and modelled atmospheric O<sub>4</sub> absorptions? An assessment of uncertainties of measurements and radiative transfer simulations for 2 selected days during the MAD-CAT campaign
- Author
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Wagner, Thomas, primary, Beirle, Steffen, additional, Benavent, Nuria, additional, Bösch, Tim, additional, Chan, Ka Lok, additional, Donner, Sebastian, additional, Dörner, Steffen, additional, Fayt, Caroline, additional, Frieß, Udo, additional, García-Nieto, David, additional, Gielen, Clio, additional, González-Bartolome, David, additional, Gomez, Laura, additional, Hendrick, François, additional, Henzing, Bas, additional, Jin, Jun Li, additional, Lampel, Johannes, additional, Ma, Jianzhong, additional, Mies, Kornelia, additional, Navarro, Mónica, additional, Peters, Enno, additional, Pinardi, Gaia, additional, Puentedura, Olga, additional, Puķīte, Janis, additional, Remmers, Julia, additional, Richter, Andreas, additional, Saiz-Lopez, Alfonso, additional, Shaiganfar, Reza, additional, Sihler, Holger, additional, Van Roozendael, Michel, additional, Wang, Yang, additional, and Yela, Margarita, additional
- Published
- 2019
- Full Text
- View/download PDF
50. Intercomparison of MAX-DOAS vertical profile retrieval algorithms: studies using synthetic data
- Author
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Frieß, Udo, primary, Beirle, Steffen, additional, Alvarado Bonilla, Leonardo, additional, Bösch, Tim, additional, Friedrich, Martina M., additional, Hendrick, François, additional, Piters, Ankie, additional, Richter, Andreas, additional, van Roozendael, Michel, additional, Rozanov, Vladimir V., additional, Spinei, Elena, additional, Tirpitz, Jan-Lukas, additional, Vlemmix, Tim, additional, Wagner, Thomas, additional, and Wang, Yang, additional
- Published
- 2019
- Full Text
- View/download PDF
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