Development of a Web-based data and product delivery system for the CSIRO AVHRR Time Series (CATS): Architecture, Interface an

Long time series of daily remote sensing data (i.e. 20 years and increasing) are useful for studies of intraand interannual behaviour of surface components, such as vegetation cover and drought monitoring, and for the derivation of surface characteristics useful for climate modeling or land cover classifications. If a time series is well calibrated, data are especially valuable to detect and interpret long term environmental changes. These data can be used operationally as a decision support tool for policy makers. The Web-CATS (CSIRO AVHRR Time Series) project provides access to the Australian AVHRR (Advanced Very High Resolution Radiometer) data archive via the World Wide Web. The data archive consists of multiple satellite overpasses from several receiving stations in Australia for almost every day since July 1981 and is still growing. The data are held online, so that products can be processed on-demand in a user-customised manner with state-of-the-art algorithms. The user is presented with a list of the possible processing operations which are implemented in CAPS (Common AVHRR Processing Software). Users can search and browse a meta-database of the archived satellite passes and specify processing parameters for their desired data product. The architecture of Web-CATS is highly modular; so that the program (with slight modification) can be used to provide a Web-based delivery system for other long-term high-frequency environmental remote sensing sensors, such as MODIS (Moderate Resolution Image Spectrometer), ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer) or future missions. Insight to this modular code is given in the appendices of this report, whilst an actual full electronic version of the package can be downloaded from the project website. This report documents the existence of Web-CATS, which provides customised user access to the long time series of AVHRR data managed and corrected using best CSIRO’s best practice algorithms. It provides a high-level technical overview of the functionality, including the underlying databases used by Web-CATS. This report does not aim to fill the role of a user-guide nor a detailed programming guide.