Author_Institution :
Observation & Data Processing Branch, Institute of Urban Meteorology, CMA, Beijing, China
Abstract :
The observation automation of cloud, energy, and sky is a principal issue to solve in the modern meteorological observation field. The results of most of the research yet done show that: it is possible to achieve the observation automation of cloud, energy, and sky, since the theory and technology is basically prepared, and some of the technology is actually very mature. In the late 20th century, scientists have started to develop a kind of digital visibility automatic monitor, which has adopted advanced digital photographic technology and image recognition technology, based on the definition of visibility and fully imitating the human eye observing visibility principle. Undoubtedly, the digital visibility automatic monitor is the best instrument to replace the manual observation of visibility. This article briefly introduces the methods of visual and instrumental observation of visibility, and elaborates the basis of the Digital Photograph Device System, its latest development, and the comparative results between Finnish Vaisala visibility instrument and manual observation. In the end, the article reaches an error analysis conclusion and discusses about the problems and further improving measures.