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sizedistribution [2021/10/01 08:52] – [3D cloud reconstructions using stereo cameras] neggerssizedistribution [2022/09/14 16:42] (current) – [3D cloud reconstructions using stereo cameras] burchart
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 ==== 3D cloud reconstructions using stereo cameras ==== ==== 3D cloud reconstructions using stereo cameras ====
  
-The SOCLES project (Stereo Observations of Clouds for LES Validation and Sub-scale Cloud Parameterizations, https://gepris.dfg.de/gepris/projekt/430226822) combines high-frequency cloud observations by multiple hemispheric cameras with high-resolution Large-Eddy Simulations (LES) at a mid-latitude continental meteorological site [[https://atmos.meteo.uni-koeln.de/ag_crewell/doku.php?id=sites:joyce|JOYCE]]. The science objective is to better understand and quantify fine-scale spatial and temporal structures of shallow cumulus cloud populations. These cloud fields are highly heterogeneous and quickly evolve on broad +{{:movie_joyce_tsi_dales_20140724-hr014_rs256_20s.mp4?&300|Time lapse movie of simulated cumulus clouds on 24 July 2014 at the JOYCE site. The ray tracing renderings are generated using the open-source Blender tool. A hemispheric projection is used, allowing comparison to Total Sky Imager (TSI) data.}} 
-range of spatial scales. This behavior has complicated their representation in numerical weather prediction and climate models. The project will fill the information gap related to fine-scale cloud structures that has hampered progress in cumulus parameterization. This problem has become more urgent with ongoing developments in supercomputingallowing for ever higher resolutions at which the conceptual basis of classic cumulus parameterizations is no longer valid. We approach this problem by exploiting the synergy between LES and stereo camera observations. The high-resolution sampling capability of stereo reconstruction in four dimensions and its considerable spatial coverage will allow us to capture cumulus cloud populations in unprecedented detail, which + 
-cannot be achieved with vertically pointing instrumentation or satellite sensors+The SOCLES project (Stereo Observations of Clouds for LES Validation and Sub-scale Cloud Parameterizations) combines high-frequency cloud observations by multiple hemispheric cameras with high-resolution Large-Eddy Simulations (LES) at the [[https://atmos.meteo.uni-koeln.de/ag_crewell/doku.php?id=sites:joyce|JOYCE]] meteorological site. The main science objective is to better understand and quantify the fine-scale spatial and temporal structures of shallow cumulus cloud populations. These transient cloud fields are highly heterogeneousa behavior that has complicated their representation in numerical weather prediction and climate models for decades 
 + 
 +SOCLES aims to fill a critical data gap concerning cumulus cloud geometry with new tools and methodsthus creating new opportunities for making progress. The high-resolution sampling capability of stereo reconstruction in four dimensions, combined with its considerable spatial coverage, allows capturing cumulus cloud populations in unprecedented detail. The LES realizations supplement this observational dataused as a virtual laboratory for gaining insight and for testing measurement strategies. Assessing the realism of the LES is of key importance, involving the determination of the resolution at which simulated cloud irregularity starts to match the stereo camera observations. For this purpose, the open source [[http://blender.org|Blender]] tool and its path-tracing engine are used to generate realistic renderings of three-dimensional cloud fields from LES, including optical effects such as absorption, scattering, sun glare, and haze effects. Among others, hemispheric projections are used as a camera instrument simulator for LES, exactly mimicking the way visual instruments like Total Sky Imagers (TSI) view the world. This allows a fair comparison between models and measurements. An example hemispheric Blender movie of simulated clouds over JOYCE is shown on the right. 
 + 
 +SOCLES is an ongoing joint effort by scientists at the University of Bonn and the University of Cologne, supported by DFG: https://gepris.dfg.de/gepris/projekt/430226822
  
-{{ :movie_joyce_tsi_dales_20140724-hr014_rs256_20s.mp4 |}} 
  
-The LES realizations supplement the observational data, but also allow for the testing of measurement strategies, for example concerning the required density of the stereo camera network. Testing the realism of the LES is a first step and a major research objective, involving determination of the resolution at which simulated cloud irregularity starts to match the stereo camera observations. To this purpose we make use of [[http://blender.org|Blender]] and its ray-tracing engine. This allows realistic rendering of three-dimensional cloud fields from LES, including optical effects such as absorption, scattering, sun glare and haze effects. Hemispheric blender projections are also used as a camera instrument simulator for LES, exactly mimicking the way visual instruments like Total Sky Imagers (TSI) view the world. This allows a fair comparison between model and measurements. An example hemispheric Blender movie of simulated clouds over JOYCE is shown above.  
  
  
sizedistribution.1633071175.txt.gz · Last modified: 2021/10/01 08:52 by neggers