A5079754145- Arctic and Antarctic ice dynamics
- Cryospheric studies and observations
- Meteorological Phenomena and Simulations
- Atmospheric and Environmental Gas Dynamics
- Climate variability and models
- Climate change and permafrost
- Atmospheric aerosols and clouds
- Methane Hydrates and Related Phenomena
- Icing and De-icing Technologies
- Atmospheric chemistry and aerosols
- Wind and Air Flow Studies
- Oceanographic and Atmospheric Processes
- Aerospace and Aviation Technology
- Spacecraft Design and Technology
- Infrared Target Detection Methodologies
- Aerospace Engineering and Energy Systems
- Advanced Measurement and Detection Methods
- Fluid Dynamics and Turbulent Flows
- Geophysics and Gravity Measurements
- Geological Studies and Exploration
- Spacecraft and Cryogenic Technologies
- Gas Dynamics and Kinetic Theory
- Calibration and Measurement Techniques
- Scientific Research and Discoveries
- Target Tracking and Data Fusion in Sensor Networks
Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung
2015-2024
Leipzig University
2024
Australian Wool Innovation (Australia)
2016
Abstract Clouds play an important role in Arctic amplification. This term represents the recently observed enhanced warming of relative to global increase near-surface air temperature. However, there are still knowledge gaps regarding interplay between clouds and aerosol particles, surface properties, as well turbulent radiative fluxes that inhibit accurate model simulations climate system. In attempt resolve this so-called cloud puzzle, two comprehensive closely coordinated field studies...
A new German research consortium is investigating why near-surface air temperatures in the Artic are rising more quickly than rest of world.
Abstract One of the most intense air mass transformations on Earth happens when cold flows from frozen surfaces to much warmer open water in cold-air outbreaks (CAOs), a process captured beautifully satellite imagery. Despite ubiquity CAO cloud regime over high-latitude oceans, we have rather poor understanding its properties, role energy and cycles, treatment weather climate models. The Cold-Air Outbreaks Marine Boundary Layer Experiment (COMBLE) was conducted better understand this...
RÉSUMÉDeux algorithmes ont été utilisés dans un schéma hybride pour dériver des cartes de concentration glace mer à une résolution 12 km partir données SSM/I (Special Sensor Microwave Imager). Un est basé sur la différence polarisation 85 GHz. Le second algorithme celui l'équipe NASA utilisant les canaux 19 et 37 L'utilisation GHz apporte amélioration importante comparativement aux Dans ce cas, il faut toutefois prendre en considération plus grande opacité atmosphérique affectant mesures...
The maximum effect of open leads within sea ice on the near‐surface atmospheric temperature is estimated using a 1D model coupled with thermodynamic snow/sea model. study restricted to clear‐sky conditions during polar night. initialized typical wintertime profile. Results are analyzed at different integration times corresponding fetches over fractured as function wind speed and concentration A . results demonstrate that for > 90% small changes in fraction have strong temperature. change...
A hierarchy of parametrizations the neutral 10 m drag coefficients over polar sea ice with different morphology regimes is derived on basis a partitioning concept that splits total surface into contributions skin and form drag. The new derivation, which provides as function concentration characteristic length scales roughness elements, needs fewer assumptions than previous similar approaches. It shown variability can explain in marginal zone (MIZ) summertime inner Arctic regions. In MIZ,...
Abstract. The two concerted field campaigns, Arctic CLoud Observations Using airborne measurements during polar Day (ACLOUD) and the Physical feedbacks of planetary boundary level Sea ice, Cloud AerosoL (PASCAL), took place near Svalbard from 23 May to 26 June 2017. They were focused on studying mixed-phase clouds involved observations airplanes (ACLOUD), an icebreaker (PASCAL) a tethered balloon, as well ground-based stations. Here, we present synoptic development 35-day period using...
Abstract. The concept of cloud radiative forcing (CRF) is commonly applied to quantify the impact clouds on surface energy budget (REB). In Arctic, specific interactions between microphysical and macrophysical properties strongly modify warming or cooling effect clouds, complicating estimate CRF obtained from observations models. Clouds tend increase broadband albedo over snow sea ice surfaces compared cloud-free conditions. However, this not adequately considered in derivation Arctic so...
Near‐surface meteorological observations and rawinsonde soundings from Arctic cruises with the German icebreaker RV Polarstern during August 1996, 2001, 2007 are compared each other ERA‐Interim reanalyses. Although usually applied in reanalysis, they differ considerably ERA data. overestimates relative humidity temperature atmospheric boundary layer base height of capping inversion. Warm biases near‐surface temperatures amount up to 2 K. The melting point snow is most frequent ERA, while...
Abstract The interaction between sea ice and atmosphere depends strongly on the near‐surface transfer coefficients for momentum heat. A parametrization of these is developed basis an existing drag neutral stratification that accounts form caused by edges floes melt ponds. This scheme extended to better account dependence surface wind limiting cases high low concentration include stability effects over open water drag. correction formulated functions from Monin‐Obukhov similarity theory also...
Abstract Over the polar oceans, near‐surface atmospheric transport of momentum is strongly influenced by sea‐ice surface topography. The latter analyzed on basis laser altimeter data obtained during airborne campaigns between 1995 and 2011 over more than 10,000 km flight distance in different regions Arctic Ocean. Spectra height spacing topographic features averaged 10 sections show that typical values are 0.45 m for mean about 20 spacing. Nevertheless, variability high spatial stronger...
Abstract. The Arctic CLoud Observations Using airborne measurements during polar Day (ACLOUD) campaign was carried out north-west of Svalbard (Norway) between 23 May and 6 June 2017. objective ACLOUD to study boundary layer mid-level clouds their role in amplification. Two research aircraft (Polar 5 6) jointly performed 22 flights over the transition zone open ocean closed sea ice. Both were equipped with identical instrumentation for basic meteorological parameters, as well turbulent...
Unmanned aerial systems (UAS) fill a gap in high-resolution observations of meteorological parameters on small scales the atmospheric boundary layer (ABL). Especially remote polar areas, there is strong need for such detailed with different research foci. In this study, three are presented which have been adapted to particular needs operating harsh environments: The fixed-wing aircraft M 2 AV mass 6 kg, quadrocopter ALICE 19 and ALADINA almost 25 kg. For all systems, their modifications...
Abstract. Global warming is amplified in the Arctic. However, numerical models struggle to represent key processes that determine Arctic weather and climate. To collect data help constrain models, HALO–(𝒜𝒞)3 aircraft campaign was conducted over Norwegian Greenland seas, Fram Strait, central Ocean March April 2022. The focused on one specific challenge posed by namely reasonable representation of transformations air masses during their meridional transport into out via northward moist-...
Leads are elongated channels in sea ice which play an important role for the heat and moisture exchange between polar ocean atmosphere. The aircraft campaign STABLE aimed to improve our current understanding of formation convective plumes over leads their impact on atmospheric boundary layer. It was carried out pack northern Fram Strait March 2013. We present case studies layer modification turbulent fluxes four wide leads, differed strongly with respect lead characteristics environmental...
The main aim of this paper is to explore the potential combining measurements from fixed- and rotary-wing remotely piloted aircraft systems (RPAS) complement data sets radio soundings as well ship sea-ice-based instrumentation for atmospheric boundary layer (ABL) profiling. This study represents a proof-of-concept RPAS observations in Antarctic sea-ice zone. We present first results RV Polarstern winter expedition Weddell Sea June–August 2013, during which three were operated measure...
Two airborne field campaigns focusing on observations of Arctic mixed-phase clouds and boundary layer processes their role with respect to amplification have been carried out in spring 2019 late summer 2020 over the Fram Strait northwest Svalbard. The latter campaign was closely connected Multidisciplinary drifting Observatory for Study Climate (MOSAiC) expedition. Comprehensive datasets cloudy atmosphere collected by operating remote sensing instruments, in-situ probes, instruments...
Abstract. Airborne in situ cloud measurements were carried out over the northern Fram Strait between Greenland and Svalbard spring 2019 summer 2020. In total, 811 min of low-level observations performed during 20 research flights above sea ice open Arctic ocean with Polar 5 aircraft Alfred Wegener Institute. Here, we combine comprehensive data to investigate distributions particle number concentration N, effective diameter Deff, water content CWC (liquid ice) clouds below 500 m altitude,...
Abstract. The global warming is amplified in the Arctic. To collect data that help to constrain weather and climate models, which often do not realistically represent enhanced Arctic warming, HALO-(AC)³ aircraft campaign was conducted March April 2022 over Norwegian Greenland Seas, Fram Strait, central Ocean. Observations were made areas of open ocean, marginal sea ice zone, ice. Two low-flying one long-range, high-altitude research have been employed. Whenever possible, three flown...