| dc.contributor.advisor | Bodenschatz, Eberhard Prof. Dr. | |
| dc.contributor.author | Schröder, Marcel | |
| dc.date.accessioned | 2023-04-14T16:06:39Z | |
| dc.date.available | 2023-04-21T00:50:10Z | |
| dc.date.issued | 2023-04-14 | |
| dc.identifier.uri | http://resolver.sub.uni-goettingen.de/purl?ediss-11858/14620 | |
| dc.identifier.uri | http://dx.doi.org/10.53846/goediss-9830 | |
| dc.format.extent | XXX Seiten | de |
| dc.language.iso | eng | de |
| dc.rights.uri | http://creativecommons.org/licenses/by/4.0/ | |
| dc.subject.ddc | 530 | de |
| dc.title | Cloud Microphysics Investigations with the Cloudkite Laboratory | de |
| dc.type | doctoralThesis | de |
| dc.contributor.referee | Bodenschatz, Eberhard Prof. Dr. | |
| dc.date.examination | 2023-03-02 | de |
| dc.subject.gok | Physik (PPN621336750) | de |
| dc.description.abstracteng | Clouds are crucial to the Earth’s radiation budget and energy balance. Inadequately
resolved cloud processes are a major source of uncertainty in weather forecasts and
climate prediction. Due to their turbulent nature, cloud dynamics span a vast range of
spatial and temporal scales from μm to km and ms to h, respectively. Together with
phase transitions, the transport of heat and moisture as well as cloud droplet-turbulence
interaction, the multiscale property of turbulence poses a huge challenge for unraveling
cloud processes. Deployed by kite-stabilized and helium-filled aerostats, the so-called
helikites, two specially designed instruments, the Max-Planck-Cloudkite + (MPCK+)
and the mini-Max-Planck-Cloudkite (mini-MPCK), measure the atmospheric state
and flow velocity as well as cloud microphysical properties. During EUREC4A field
campaign in the Caribbean from January to February 2020 above the Atlantic Ocean,
both the MPCK+ and the mini-MPCK profiled the atmospheric boundary layer of the
trade-wind region and sampled clouds. In this thesis, we report measurements of the
energy dissipation rate and cloud droplet statistics in the trade-wind region.
The energy dissipation rate is one of the most fundamental turbulence characteristics
and is estimated from one-dimensional velocity time-records. To benchmark different
methods for estimating the energy dissipation rate, each method is compared to the
ground-truth reference of direct numerical simulation (DNS) of stationary homogeneous
isotropic turbulence at different Taylor-scale Reynolds numbers between 74 and 321. The
impact of finite turbulence intensity and misalignment between the probe orientation
and the mean flow direction is systematically studied and expressed by analytical
expressions. Additionally, the effect of a finite averaging window and its Rλ dependence
is captured by scaling arguments which are compared to hot-wire measurements from
the Max Planck Variable Density Turbulence Tunnel with Taylor-scale Reynolds numbers between 147 and 5864.
Both atmospheric turbulence and cloud droplet-turbulence interaction is investigated
with the help of energy dissipation rate estimates from, in total, 197 h record of scientific
data. This thesis examines the spatial distribution of cloud droplets in trade-wind
cumuli, the onset of warm-rain initiation and the altitude dependence of the cloud
droplet size distribution, which are analyzed based on 144 h of cloud droplet records.
Furthermore, turbulence characteristics of the boundary layer, its stability and isotropy
on inertial length scales are determined. | de |
| dc.contributor.coReferee | Wilczek, Michael Prof. Dr. | |
| dc.subject.eng | cloud microphysics | de |
| dc.subject.eng | atmospheric turbulence | de |
| dc.subject.eng | energy dissipation rate | de |
| dc.identifier.urn | urn:nbn:de:gbv:7-ediss-14620-0 | |
| dc.affiliation.institute | Fakultät für Physik | de |
| dc.description.embargoed | 2023-04-21 | de |
| dc.identifier.ppn | 1842977334 | |
| dc.notes.confirmationsent | Confirmation sent 2023-04-17T06:15:01 | de |