Automatic cloud top height determination in mountainous areas using a cost-effective time-lapse camera system
- 1Laboratory for Climatology and Remote Sensing, Faculty of Geography, Philipps University, Marburg, Germany
- 2Department of Natural Resources and Environmental Studies, National Dong Hwa University, Hualien, Taiwan
Abstract. A new method is presented for the determination of cloud top heights using the footage of a time-lapse camera that is placed above a frequently occurring cloud layer in a mountain valley. Contact points between cloud tops and underlying terrain are automatically detected in the camera image based on differences in the brightness, texture and movement of cloudy and non-cloudy areas. The height of the detected cloud top positions is determined by comparison with a digital elevation model projected to the view of the camera. The technique has been validated using data about the cloud immersion of a second camera as well as via visual assessment. The validation shows a high detection quality, especially regarding the requirements for the validation of satellite cloud top retrieval algorithms.