A5072138949- Atmospheric chemistry and aerosols
- Atmospheric and Environmental Gas Dynamics
- Plant Water Relations and Carbon Dynamics
- Atmospheric aerosols and clouds
- Plant responses to elevated CO2
- Atmospheric Ozone and Climate
- Air Quality Monitoring and Forecasting
- Fluid Dynamics and Turbulent Flows
- Environmental and biological studies
- Climate variability and models
- Air Quality and Health Impacts
- Remote Sensing in Agriculture
- Aeolian processes and effects
- Geography and Environmental Studies
- Meteorological Phenomena and Simulations
- Marine and coastal ecosystems
- Soil and Water Nutrient Dynamics
- Fire effects on ecosystems
- Geophysics and Gravity Measurements
- Water Quality and Pollution Assessment
- Vehicle emissions and performance
- Biocrusts and Microbial Ecology
- Isotope Analysis in Ecology
- Hydrology and Sediment Transport Processes
- Solar and Space Plasma Dynamics
Max Planck Institute for Chemistry
2015-2024
Max Planck Institute for Biogeochemistry
2014-2021
Leuphana University of Lüneburg
2019
University of Bayreuth
2009-2015
National Institute of Amazonian Research
2015
Max Planck Society
2013
Instituto Nacional de Técnica Aeroespacial
2012
From Soil to Sky Trace gases emitted either through the activity of microbial communities or from abiotic reactions in soil influence atmospheric chemistry. In laboratory column experiments using several types, Oswald et al. (p. 1233 ) showed that soils arid regions and farmlands can produce substantial quantities nitric oxide (NO) nitrous acid (HONO). Ammonia-oxidizing bacteria are primary source HONO at comparable levels NO, thus serving as an important reactive nitrogen atmosphere.
Abstract. The Amazon Basin plays key roles in the carbon and water cycles, climate change, atmospheric chemistry, biodiversity. It has already been changed significantly by human activities, more pervasive change is expected to occur coming decades. therefore essential establish long-term measurement sites that provide a baseline record of present-day climatic, biogeochemical, conditions will be operated over decades monitor region, as perturbations increase future. Tall Tower Observatory...
Significance Biological soil crusts (biocrusts), occurring on ground surfaces in drylands throughout the world, are among oldest life forms consisting of cyanobacteria, lichens, mosses, and algae plus heterotrophic organisms varying proportions. They prevent erosion nurture ecosystems by fixing carbon nitrogen from atmosphere. Here, we show that fixed is processed within biocrusts, during this metabolic activity, oxide nitrous acid released to Both these gases highly relevant, as they...
Dry deposition of ozone is an important sink in near surface air. When dry occurs through plant stomata, can injure the plant, altering water and carbon cycling reducing crop yields. Quantifying both stomatal nonstomatal uptake accurately relevant for understanding ozone's impact on human health as air pollutant climate a potent short-lived greenhouse gas primary control removal several reactive gases pollutants. Robust estimates require knowledge relative importance individual pathways, but...
Abstract. During the DOMINO (Diel Oxidant Mechanism In relation to Nitrogen Oxides) campaign in southwest Spain we measured simultaneously all quantities necessary calculate a photostationary state for HONO gas phase. These comprise concentrations of OH, NO, and photolysis frequency NO2, j(NO2) as proxy j(HONO). This allowed us values unknown daytime source. source, normalized by NO2 mixing ratios expressed conversion (% h−1), showed clear dependence on with up 43% h−1 at noon. We compared...
Abstract. Black carbon (BC) aerosols influence the Earth's atmosphere and climate, but their microphysical properties, spatiotemporal distribution, long-range transport are not well constrained. This study presents airborne observations of transatlantic BC-rich African biomass burning (BB) smoke into Amazon Basin using a Single Particle Soot Photometer (SP2) as several complementary techniques. We base our results on trace gases off Brazilian coast onboard HALO (High Altitude LOng range)...
Abstract. We have combined chemical and micrometeorological measurements to investigate the formation distribution of HONO throughout a forest canopy. was measured simultaneously at two heights, close floor just above The turbulent exchange between atmosphere studied using vertical profiles eddy covariance wind velocity, sonic temperature, water vapour CO2. mixing ratios both heights showed typical diel cycles with low daytime values (~80 ppt) high nighttime (up 500 ppt), but were influenced...
Abstract. To investigate the energy, matter and reactive non-reactive trace gas exchange between atmosphere a spruce forest in German mountain region, two intensive measuring periods were conducted at FLUXNET site DE-Bay (Waldstein-Weidenbrunnen) September/October 2007 June/July 2008. They part of project "ExchanGE processes mountainous Regions" (EGER). Beyond brief description experiment, main focus paper concerns coupling trunk space, canopy above-canopy atmosphere. Therefore, relevant...
Abstract. The Amazon rain forest experiences the combined pressures from human-made deforestation and progressing climate change, causing severe potentially disruptive perturbations of ecosystem's integrity stability. To intensify research on critical aspects Amazonian biosphere–atmosphere exchange, Tall Tower Observatory (ATTO) has been established in central Basin. Here we present a multi-year analysis backward trajectories to derive an effective footprint region observatory, which spans...
Abstract. Atmospheric concentrations of nitrous acid (HONO), one the major precursors hydroxyl radical (OH) in troposphere, significantly exceed values predicted by assumption a photostationary state (PSS) during daytime. Therefore, additional sources HONO were intensively investigated last decades. This study presents budget calculations based on simultaneous measurements all relevant species, including and OH at two different measurement heights, i.e. 1 m above ground about 2 to 3 canopy...
Abstract Nitrous acid (HONO) is an important precursor of the hydroxyl radical (OH), atmosphere´s primary oxidant. An unknown strong daytime source HONO required to explain measurements in ambient air. Emissions from soils are one potential sources. Ammonia-oxidizing bacteria (AOB) have been identified as possible producers these soil emissions. However, mechanisms for production and release not fully understood. In this study, we used a dynamic soil-chamber system provide direct evidence...
Abstract. Vertical mixing ratio profiles of nitrous acid (HONO) were measured in a clearing and on the forest floor rural environment. For floor, HONO was found to predominantly deposit, whereas for clearing, net deposition dominated only during nighttime emissions observed daytime. selected days, fluxes calculated from using aerodynamic gradient method. The emission range 0.02 0.07 nmol m−2 s−1 thus lower previous observations. These compared strengths postulated sources. Laboratory...
Abstract. The tropical forests are Earth's largest source of biogenic volatile organic compounds (BVOCs) and thus also the atmospheric sink region for hydroxyl radical (OH). However, OH above is poorly understood, as past studies have revealed large unattributed fractions total reactivity. We present first reactivity compound (VOC) measurements made at Amazon Tall Tower Observatory (ATTO) 80, 150, 320 m ground level, covering two dry seasons, one wet season, transition season in 2018–2019....
The atmospheric boundary layer height (zi) is a key parameter in the vertical transport of mass, energy, moisture, and chemical species between surface free atmosphere. There lack long-term continuous observations zi, however, particularly for remote regions, such as Amazon forest. Reanalysis products, ERA5, can fill this gap by providing temporally spatially resolved information on zi. In work, we evaluate ERA5 estimates zi (zi-ERA5) two locations corrected them means ceilometer,...
Abstract On the basis of measurements over different surfaces, an inertial sublayer (ISL), where Monin‐Obukhov Similarity Theory applies, exists above z =3 h , is canopy height. The roughness within < <3 . Most studies surface layer forests, however, are able to probe only a narrow region Therefore, direct verification ISL tall forests difficult. In this study we conducted systematic analysis unstable turbulence characteristics at heights from 40 325 m, measured 80m, and recently built...
Abstract. We study the interactions between atmospheric boundary layer (ABL) dynamics and chemistry using a mixed-layer model coupled to chemical reaction schemes. Guided by both measurements obtained during DOMINO (Diel Oxidant Mechanisms in relation Nitrogen Oxides) campaign (2008), numerical experiments are performed role of ABL accuracy schemes with different complexity: Model for Ozone Related Tracers, version 4 (MOZART-4) reduced mechanism this system. Both produce satisfactory...
Abstract Observational data from two field campaigns in the Amazon forest were used to study vertical structure of turbulence above forest. The analysis was performed using reduced turbulent kinetic energy (TKE) budget and its associated two-dimensional phase space. Results revealed existence regions within roughness sublayer which TKE cannot be explained by canonical flat-terrain budgets canopy or lower portion convective ABL. Data also suggested that deviations horizontal homogeneity have...
Abstract This study investigates the influence of leaf surface water films on deposition ozone (O 3 ) and peroxyacetyl nitrate (PAN) under controlled laboratory conditions. A twin‐cuvette system was used to simulate environmental variables. We observed a clear correlation between O plants ( Quercus ilex relative humidity (RH) both light dark During period increase mainly attributed opening stomata, while during absence liquid were reason for deposition. finding supported by experimentally...
Abstract. In this study, high-frequency, multilevel measurements, performed from late October to mid-November of 2015 at a 80 m tall tower the Amazon Tall Tower Observatory (ATTO) project in central state Amazonas, Brazil, were used diagnose evolution thermodynamic and kinematic variables as well scalar fluxes during passage outflows generated by deep moist convection (DMC). Outflow associated with DMC activity over or near was identified through analysis storm echoes base reflectivity data...
Abstract Cryptogamic organisms such as bryophytes and lichens cover most surfaces within tropical forests, yet their impact on the emission of biogenic volatile organic compounds is unknown. These can strongly influence atmospheric oxidant levels well secondary aerosol concentrations, forest canopy leaves have been considered dominant source these emissions. Here we present cuvette flux measurements, made in Amazon rainforest between 2016–2018, show that common emit large quantities highly...