虚拟地理环境中尺度适宜性问题的探讨

Discussion about scale adaptability in virtual geographic environments

本文沿着地理学语言的演化过程,讨论了地理学中尺度概念的演变;针对虚拟地理环境的框架结构,依据尺度概念的维度、类别和组成因素分析了四组尺度适宜性问题,并讨论了在虚拟地理环境搭建和应用过程中各种尺度适宜性之间的关系。以香港区域气象过程模拟为例,应用多尺度地形数据和模型,简要分析了在空间维上,测量尺度类别中组成因素(分辨率)层次的尺度适宜性。该案例不只表明尺度适宜性对动态地理过程问题求解的重要影响,同时表明对尺度适宜性的讨论有助于其认知与分解,丰富虚拟地理环境的理论与方法。

Along with the focuses of geography changing from static geographic pattern to dynamic geographic process, geographic language is also evolving from maps to GISystem （Geographic Information System） to VGEs （Virtual Geographic Environments）. Due to the multiscale characteristic and scale dependence of both geographic processes and study methods, scale adaptability turns out to be an inventible component for the theory and method of VGEs, which aims to solve dynamic geographic problems. This paper discussed the definition of geographic scale by using three parameters, namely dimension, kind and component, and then illustrated the evolution of scale concept along with the evolution of geographic language. In such evolution, from maps to VGEs, the scale concept is becoming much more comprehensive, which makes the study into scale adaptability issues more important and difficult. In regard to the framework of VGEs, four groups of scale adaptability issues are identified and analyzed according to the parameters of scale definition （dimension, kind and component）. These four groups reflect different operational levels, which are illustrated in detail to support the implementation of scale adaptability. Meanwhile, the interrelationship among multiple scale adaptability is also illustrated when the VGEs are constructed and applied. Taking a meteorological simulation in Hong Kong as a case study, scale adaptability considering multiscale DEM data and a meteorological model （WRF： Weather Research ＆ Forecasting Model） was investigated, which is on the component level within the spatial dimension and observational kind of scale （namely spatial resolution）. This case study not only explained the significance and implementation of scale adaptability in geographic process research, but also showed the contribution to the cognition and decomposition of complex scale adaptability issues from the discussion in this paper. In summary, the attention and research into scale adaptability will enrich the theory and methodoloav of VGEs and imorove oractical aoolications of VGEs.