EOL Seminar: Stereophotogrammetry of Clouds

Tuesday, October 18, 2016 - 15:30 to 16:30
FL2-1022 Main Auditorium
Contact Name: 
Holger Voemel
Contact Email: 
Contact Phone: 

Stereophotogrammetry of Clouds


Ulrike Romatschke

National Center for Atmospheric Research

Stereophotogrammetry is the reconstruction of three dimensional (3D) models based on the position of key points visible in two photographs capturing the same scene. The high temporal and spatial resolution of the data makes the technique a highly valuable but little utilized tool for the analysis of smaller scale, highly ephemeral clouds. However, the often blurred nature of clouds makes the available commercial and open source photogrammetry software prone to errors and even complete failure when applied to cloud images. Building upon recent studies we have been able to develop algorithms specifically geared towards cloud modeling which handle all fundamental steps of photogrammetric analysis: camera calibration, automatic feature matching, and reconstruction of 3D cloud models.


These newly developed algorithms have been applied to stereo images collected during the T-REX field campaign, which took place in 2006 in the lee of the Sierra Nevada in eastern California. On several days during T-REX, a largely stationary rotor cloud was observed over Owens Valley. Small cloud fragments often formed just upstream of this stationary cloud, moving towards the main cloud and eventually being subsumed by it. Studying the 3D models of these small scale cloud fragments, we can follow their evolution in 3D space and time, and quantify their physical properties and dynamics such as growth, horizontal and vertical movement.


Seminar will be webcast at: http://www.fin.ucar.edu/it/mms/fl-live.htm


Tuesday, 18 October 2016, 3:30 PM

Refreshments 3:15 PM

NCAR-Foothills Laboratory

3450 Mitchell Lane

Bldg 2 Main Auditorium (1022)