Results 21 to 30 of about 14,750 (194)

Evaluation of methods for gravity wave extraction from middle-atmospheric lidar temperature measurements [PDF]

Atmospheric Measurement Techniques, 2015
This study evaluates commonly used methods of extracting gravity-wave-induced temperature perturbations from lidar measurements. The spectral response of these methods is characterized with the help of a synthetic data set with known ...
B. Ehard, B. Kaifler, N. Kaifler, M. Rapp   +3 more
doaj   +1 more source

Validation of the Aeolus L2B wind product with airborne wind lidar measurements in the polar North Atlantic region and in the tropics [PDF]

Atmospheric Measurement Techniques, 2022
During the first 3 years of the European Space Agency's Aeolus mission, the German Aerospace Center (Deutsches Zentrum für Luft- und Raumfahrt, DLR) performed four airborne campaigns deploying two different Doppler wind lidars (DWL) on board the DLR ...
B. Witschas, C. Lemmerz, A. Geiß, O. Lux, U. Marksteiner, S. Rahm, O. Reitebuch, A. Schäfler, F. Weiler   +8 more
doaj   +1 more source

Determining stages of cirrus evolution: a cloud classification scheme [PDF]

Atmospheric Measurement Techniques, 2017
Cirrus clouds impose high uncertainties on climate prediction, as knowledge on important processes is still incomplete. For instance it remains unclear how cloud microphysical and radiative properties change as the cirrus evolves. Recent studies classify
B. Urbanek, S. Groß, A. Schäfler, M. Wirth   +3 more
doaj   +1 more source

Measurement report: In-flight and ground-based measurements of nitrogen oxide emissions from latest-generation jet engines and 100 % sustainable aviation fuel [PDF]

Atmospheric Chemistry and Physics
Nitrogen oxides, emitted from air traffic, are of concern due to their impact on climate by changing atmospheric ozone and methane levels. Using the DLR research aircraft Falcon, total reactive nitrogen (NOy) in-flight measurements were carried out at ...
T. Harlass, R. Dischl, R. Dischl, S. Kaufmann, R. Märkl, R. Märkl, D. Sauer, M. Scheibe, P. Stock, T. Bräuer, T. Bräuer, A. Dörnbrack, A. Roiger, H. Schlager, U. Schumann, M. Pühl, T. Schripp, T. Grein, L. Bondorf, C. Renard, M. Gauthier, M. Johnson, D. Luff, P. Madden, P. Swann, D. Ahrens, R. Sallinen, C. Voigt, C. Voigt   +28 more
doaj   +1 more source

Horizontal Wavenumber Spectra Across the Middle Atmosphere From Airborne Lidar Observations During the 2019 Southern Hemispheric SSW

Geophysical Research Letters, 2023
Horizontal wavenumber spectra across the middle atmosphere are investigated based on density measurements with the Airborne Lidar for Middle Atmosphere research (ALIMA) in the vicinity of the Southern Andes, the Drake passage and the Antarctic peninsula ...
Stefanie Knobloch, Bernd Kaifler, Andreas Dörnbrack, Markus Rapp   +3 more
doaj   +1 more source

COVID-19 induced lower-tropospheric ozone changes

Environmental Research Letters, 2021
The recent COVID-19 pandemic with its countermeasures, e.g. lock-downs, resulted in decreases in emissions of various trace gases. Here we investigate the changes of ozone over Europe associated with these emission reductions using a coupled global ...
Mariano Mertens, Patrick Jöckel, Sigrun Matthes, Matthias Nützel, Volker Grewe, Robert Sausen   +5 more
doaj   +1 more source

Airborne observations of the Eyjafjalla volcano ash cloud over Europe during air space closure in April and May 2010 [PDF]

Atmospheric Chemistry and Physics, 2011
Airborne lidar and in-situ measurements of aerosols and trace gases were performed in volcanic ash plumes over Europe between Southern Germany and Iceland with the Falcon aircraft during the eruption period of the Eyjafjalla volcano between 19 April and ...
U. Schumann, B. Weinzierl, O. Reitebuch, H. Schlager, A. Minikin, C. Forster, R. Baumann, T. Sailer, K. Graf, H. Mannstein, C. Voigt, S. Rahm, R. Simmet, M. Scheibe, M. Lichtenstern, P. Stock, H. Rüba, D. Schäuble, A. Tafferner, M. Rautenhaus, T. Gerz, H. Ziereis, M. Krautstrunk, C. Mallaun, J.-F. Gayet, K. Lieke, K. Kandler, M. Ebert, S. Weinbruch, A. Stohl, J. Gasteiger, S. Groß, V. Freudenthaler, M. Wiegner, A. Ansmann, M. Tesche, H. Olafsson, K. Sturm   +37 more
doaj   +1 more source

Data assimilation of generic boundary layer flows for wind turbine applications – an LES study [PDF]

Wind Energy Science
Providing date- and site-specific turbulent inflow fields for large-eddy simulations (LESs) of the flow through wind turbines becomes increasingly important for reliable estimates of power production.
L. Wrba, A. Englberger, A. Dörnbrack, G. Kilroy, N. Wildmann   +4 more
doaj   +1 more source

Hindcasting and forecasting of regional methane from coal mine emissions in the Upper Silesian Coal Basin using the online nested global regional chemistry–climate model MECO(n) (MESSy v2.53) [PDF]

Geoscientific Model Development, 2020
Methane is the second most important greenhouse gas in terms of anthropogenic radiative forcing. Since pre-industrial times, the globally averaged dry mole fraction of methane in the atmosphere has increased considerably.
A.-L. Nickl, M. Mertens, A. Roiger, A. Fix, A. Amediek, A. Fiehn, C. Gerbig, M. Galkowski, M. Galkowski, A. Kerkweg, A. Kerkweg, T. Klausner, M. Eckl, P. Jöckel   +13 more
doaj   +1 more source

How well can brightness temperature differences of spaceborne imagers help to detect cloud phase? A sensitivity analysis regarding cloud phase and related cloud properties [PDF]

Atmospheric Measurement Techniques
This study investigates the sensitivity of two brightness temperature differences (BTDs) in the infrared (IR) window of the Spinning Enhanced Visible and Infrared Imager (SEVIRI) to various cloud parameters in order to understand their information ...
J. Mayer, B. Mayer, B. Mayer, L. Bugliaro, R. Meerkötter, C. Voigt, C. Voigt   +6 more
doaj   +1 more source