大气遥感:PhD at Leipzig University, Germany
学术
2024-07-02 18:13
比利时
Faculty for Physics and Earth System Sciences Leipzig Institute for Meteorology The Leipzig Institute for Meteorology (LIM), Leipzig University, Germany, invites applications for one
PhD Position on
Solar radiation enhancement by clouds: Effects on the cloud radiative energy budget and new
particle formation using airborne and satellite observations The position is related to the international research project HALO-South (https://haloresearch.de/sience/future-missions/halo-south/) and is part of the Scientific Priority Program SPP 1294
(www.halo-spp.de) funded by the German Research Foundation (DFG, Deutsche
Forschungsgemeinschaft). Within the HALO-South project, a one-month research campaign including the
German High Altitude and Long Range Research Aircraft (HALO) is planned for October 2025. During this
mission, a suite of remote sensing, cloud and aerosol instruments will be operated aboard of HALO to
investigate the radiative, macrophysical, and microphysical properties of convective clouds in the southern
hemisphere. The position (65% TV-L E13) is awarded for three years, starting as soon as possible. We offer a productive
and interdisciplinary working group (https://www.physes.uni-leipzig.de/institut-fuermeteorologie/forschung/arbeitsgruppeatmosphaerischestrahlung/forschung) including comprehensive
supervision and integration into the Leipzig Graduate School on Clouds, Aerosol and Radiation
(https://www.tropos.de/en/teaching/doctorate/leipzig-graduate-school). Detailed project descriptions The core objective of the project is to identify and quantify events of solar radiation enhancement in
terms of actinic flux densities, photolysis frequencies, irradiances, and the cloud radiative effect.
Cloud induced enhancement of solar radiation may contribute to uncertainties in global climate models
cloud properties and related radiative effects, especially for clouds in the Southern Ocean which significantly
contribute to the global top-of-atmosphere radiative energy budget. Airborne observations embedded in the
HALO-South mission will be used in order to obtain data at altitudes, where radiation enhancement is
expected to be significant: above and within cloud top, between broken clouds, and below cirrus. The
airborne measurements will be evaluated by both, specific events and from a statistical point of view to
investigate, if solar radiation enhancement is correlated with new particle formation and exerts a significant
influence on the cloud radiative energy budget in the Southern Ocean. In combination with satellite
observations, the in-situ airborne measurements will be used to test and quantify how strongly the frequency
and magnitude of radiation enhancement by clouds depends on macrophysical and microphysical cloud
properties. For this purpose, events of enhanced solar radiation will be extracted by comparison of the measurement to
values in cloud-free conditions simulated using radiative transfer modeling. The impact of these events on
the cloud radiative effect and on photolysis frequencies will be quantified. In collaboration with the HALOSouth consortium, in particular measurements of aerosol particle properties and trace gas concentrations,
this analysis will serve as a basis to investigate the importance of enhanced radiation on new particle
formation events. To identify which cloud regimes and cloud properties favor radiation enhancement, the
airborne observations will be merged with satellite products of cloud properties. The comparison aims to
identify correlations between cloud quantities observed from satellites with the occurrence of cloud induced
radiation enhancements as observed from HALO. The cloud properties of interest include cloud fraction,
cloud top altitude, liquid water path, effective cloud particle radius, cloud particle phase, as well as the twodimensional spatial organization and the heterogeneity of the cloud field. For more information contact: m.wendisch[at]uni-leipzig.de We expect enthusiasm and interest in atmospheric science, in particular in cloud observations, remote
sensing, and radiative transfer modelling. Applicants should have a Master-of-Science-equivalent university
degree in meteorology, geophysics, physics or mathematics. Knowledge of high-level scientific
programming for data analysis is desirable. Experience regarding experimental field work and the operation
of scientific instruments would be advantageous. The successful applicant will strongly interact with other
research groups (experimental, modelling, and satellite groups). Communication, collaboration and team
play is essential. Candidates must possess excellent communication skills both in written and spoken
English. Interested candidates should send a CV, a cover letter describing background, training and research
interests; certificates; and the contact information of at least two academic referees as a single PDF to
anja.schwarz[at]uni-leipzig.de.
Submissions will be accepted until 31 July 2024.
Interviews with the selected candidates may not start before mid of August. The selection for the candidates will be based solely on merit without regard to gender, religion, national
origin, political affiliation, marital or family status or other differences. Among equally qualified candidates,
handicapped candidates will be given preference.