A5022108289- Atmospheric aerosols and clouds
- Meteorological Phenomena and Simulations
- Climate variability and models
- Atmospheric chemistry and aerosols
- Atmospheric and Environmental Gas Dynamics
- Precipitation Measurement and Analysis
- Atmospheric Ozone and Climate
- Plant Water Relations and Carbon Dynamics
- Computational Physics and Python Applications
- Wind and Air Flow Studies
- Advanced Optical Sensing Technologies
- Aeolian processes and effects
- Oceanographic and Atmospheric Processes
- Soil Moisture and Remote Sensing
- Fire effects on ecosystems
- Forest ecology and management
- Remote Sensing in Agriculture
- Tropical and Extratropical Cyclones Research
- Wind Energy Research and Development
- Remote Sensing and LiDAR Applications
- Tree-ring climate responses
- Oil Spill Detection and Mitigation
- Solar Radiation and Photovoltaics
University of Cologne
2015-2024
University of Colorado Boulder
2020-2021
Cooperative Institute for Research in Environmental Sciences
2020-2021
NOAA Chemical Sciences Laboratory
2020-2021
NOAA Earth System Research Laboratory
2020
Finnish Meteorological Institute
2018
Vaisala (Finland)
2018
University of Helsinki
2018
Abstract We present a method using Doppler lidar data for identifying the main sources of turbulent mixing within atmospheric boundary layer. The identifies presence turbulence and then assigns source by combining several quantities: attenuated backscatter coefficient, vertical velocity skewness, dissipation rate kinetic energy, vector wind shear. Both buoyancy‐driven shear‐driven situations are identified, operates in both clear‐sky cloud‐topped conditions, with some reservations...
Abstract Low-level-jet (LLJ) periods are investigated by exploiting a long-term record of ground-based remote sensing Doppler wind lidar measurements supported tower observations and surface flux at the Jülich Observatory for Cloud Evolution (JOYCE), midlatitude site in western Germany. LLJs were found 13% time during continuous over more than 4 yr. The climatological behavior shows prevailing nighttime appearance jets, with median height 375 m speed 8.8 s −1 jet nose. Significant turbulence...
Abstract. During the Atlantic References and Convection (ARC) ship campaign with reference MSM114/2, which took place in early 2023, German research vessel Maria S. Merian travelled from Mindelo, Cape Verde, to Punta Arenas, Chile. One of main objectives ARC was obtain vertically resolved cross sections Intertropical Convergence Zone (ITCZ). To this end, we crossed ITCZ three times meridional direction. We present atmospheric oceanographic measurements collected during a standardised way...
Abstract In this article, liquid water cloud microphysical properties are retrieved by a combination of microwave and infrared ground‐based observations. Clouds containing frequently occurring in most climate regimes play significant role terms interaction with radiation. Small perturbations the amount contained can cause large variations radiative fluxes. This effect is enhanced for thin clouds (liquid path, LWP <100 g/m 2 ), which makes accurate retrieval information crucial. Due to...
Ground-based passive microwave radiometers (MWRs) are deployed to obtain information on the vertical structure of temperature and water vapor mostly in lower troposphere.In addition, they used derive total column-integrated liquid content atmosphere, referred as path (LWP).MWRs measure radiances, given brightness temperatures ( ), typically two frequency ranges along absorption features oxygen, well window regions where observations sensitive clouds.Profiles humidity retrieved together with...
Abstract Sunlight warms sea surface temperature (SST) under calm winds, increasing atmospheric buoyancy flux, turbulence, and mixed layer (ML) depth in the afternoon. The diurnal range of SST exceeded 1°C for 24% days central tropical Indian Ocean during Dynamics Madden Julian Oscillation experiment October‐December 2011. Doppler lidar shows enhancement strength height convective turbulence ML over warm turbulent kinetic energy (TKE) dissipation rate marine scales with flux like previous...
Abstract. During the Atlantic References and Convection (ARC) ship campaign with reference MSM114/2, which took place in early 2023, German research vessel Maria S. Merian travelled from Mindelo, Cape Verde, to Punta Arenas, Chile. One of main objectives ARC was obtain vertically resolved cross sections Intertropical Convergence Zone (ITCZ). To this end, we crossed ITCZ three times meridional direction. We present atmospheric oceanographic measurements collected during a standardized way...
Abstract The existence of subsiding shells on the periphery shallow cumulus clouds has major implications concerning parameterization convection, with mass exchange between shell and cloudy air representing a significant deviation from commonly used bulk‐plume parameterization. We examine structure frequency in convection using Doppler lidars at Atmospheric Radiation Measurement Southern Great Plains facility central United States Jülich ObservatorY for Cloud Evolution western Germany. lidar...
Abstract. Finding observational evidence of land surface and atmosphere interactions is crucial for understanding the spatial temporal evolution boundary layer, as well model evaluation, in particular large-eddy simulation (LES) models. In this study, influence a heterogeneous on distribution atmospheric water vapor assessed. Ground-based remote sensing measurements from scanning microwave radiometer (MWR) are used long-term study over 6 years to characterize heterogeneities integrated (IWV)...
Ground-based microwave radiometers (MWR) provide valuable information on thermodynamic profiles and cloud liquid water by measuring the thermal emission, expressed as brightness temperatures (TB), of atmospheric gases hydrometeors in several channels, have thus become a widely used tool remote sensing. MWR are being deployed for process studies boundary layer structure development, well operational data assimilation numerical weather prediction models (NWP). Due to their robustness ability...
Abstract Complex-terrain locations often have repeatable near-surface wind patterns, such as synoptic gap flows and local thermally forced flows. An example is the Columbia River Valley in east-central Oregon-Washington, a significant wind-energy-generation region site of Second Wind-Forecast Improvement Project (WFIP2). Data from three Doppler lidars deployed during WFIP2 define characterize summertime regimes their large-scale contexts, provide insight into NWP model errors by examining...
Abstract. Finding observational evidence of land surface atmosphere interactions is crucial for understanding the spatial and temporal evolution boundary layer, as well model evaluation, in particular large-eddy simulation (LES) models. In this study, influence a heterogeneous on distribution atmospheric water vapor assessed. Ground-based remote sensing measurements scanning microwave radiometer (MWR) are used long-term study over six years to characterize heterogeneities integrated (IWV)...
During June 2022 surface air temperatures across most of Europe were above the 1991-2020 average and daily maximum reached over 40 &#186;C southern (according to Copernicus.eu). Unusually high also in Germany, where heat waves took place with 35 &#186;C.&#160;In J&#252;lich Observatory for Cloud Evolution (JOYCE), these extreme temperature humidity conditions registered. JOYCE combines a rather unique set ground-based remote sensing instruments that provide information about...
Ground-based microwave radiometers (MWR) are an established tool for continuously measuring vertical profiles of temperature and humidity, as well integrated quantities like cloud liquid water path (LWP) vapor, at a high temporal resolution 1 s. An elevation scanning capability can be utilized to add angular information the spectrally resolved measurements in order enhance accuracy atmospheric boundary-layer (ABL). During last two decades, these instruments proved their network suitability...