摘要
地物波谱知识库的建立旨在满足应用需求。为达到数据的共享,波谱知识库应对遥感实验测量的波谱数据和相关信息如观测规范、实验环境有清楚的说明,即要有完备的元数据让用户知道波谱知识库中是什么样的数据。为弥补地面测量数据与用户需要数据的时间空间尺度差异,用于外延观测数据的遥感物理模型必不可少;这要求收集分析遥感物理模型,评价其适用条件并创建模型元数据,使用户了解在其工作条件下有何适用的模型,模型的依据是什么;同时波谱库使用遥感物理解析模型和计算机模拟模型完成植被参数的时间扩展和沿叶片—冠层—像元3个层次的观测尺度空间扩展,从而产生像元尺度可见光到热红外波段的参考波谱。为实现因特网上的波谱知识共享,需要研究如何组织波谱数据和模型,让用户方便地远程检索实测的典型地物波谱数据,并可以实时获取由遥感物理模型外延的波谱数据。从上述3个方面归纳了波谱库建设和服务需要解决的6个问题。
The objective of the spectral knowledge base (spectrum library) is to facilitate remote sensing applications. The paper discusses the six problems that are required to solve in constructing the spectral knowledge base and its services. Firstly, in order to share data, the spectral knowledge base should show the measured spectral data and relative information such as the observation criterion and field campaign condition etc. In other words, it is necessary to have the integrated system of spectral and environmental data and the selfcontained metadata. Secondly, for the sake of solving the discrepancy between the temporal and spatial scales of the measured spectral data and of remote sensing applications, it is essential to study quantificational descriptions of land surface parameters and approaches to convert the parameters between temporal and spatial scales. In the next place, because it is impractical to measure vegetation spectrum at all times during vegetation growth cycle, remote sensing physical models, which are used to interpolate and extrapolate the measured data, should be collected and the applicable conditions of these models will be evaluated. The remote sensing physical model, which maybe are analytic equations or computer simulation models, are used to extend vegetation parameters along temporal change, and compute the spectrum on three spatial scales such as leaf, canopy and remote sensing pixel from visible light to thermal infrared based on the measured spectral data, the extended vegetation parameters, and pixel components. Fourthly, the model metadata are defined and collected so that the users can know which models in the spectral knowledge base is suitable to their tasks and why they are. Moreover, building the model runtime support software based on metadata of data and models is an effectual approach to extract the parameters for the models and run the models automatically. Finally, in order to sharing data and model on Internet, it is need to research how manage the data and models so that the users can obtain the data and models on Internet easily and the interpolated and extrapolated the spectral data realtimely.
出处
《地球科学进展》
CAS
CSCD
2003年第2期185-191,共7页
Advances in Earth Science
基金
国家重点基础研究发展规划项目"地球表面时空多变要素的定量遥感理论及应用"(编号:G20000977)
国家自然科学基金项目"用热点卫星数据研究陆面热点"(编号:49971059)
863计划"中国典型地物波谱数据库"(编号:863 103 05 02)资助.
关键词
波谱库
元数据
遥感物理模型
遥感波谱实验
Spectrum knowledge base
Metadata
Remote sensing physical modeling
Field experiment.
