Esquerdo, JCD; Antunes, JFG; Coutinho, AC; Speranza, EA; Kondo, AA; dos Santos, JL (2020). SATVeg: A web-based tool for visualization of MODIS vegetation indices in South America. COMPUTERS AND ELECTRONICS IN AGRICULTURE, 175, 105516.

Time series of satellite images have been widely used in a range of applications, specially involving the green biomass monitoring in the Earth surface. A set of land surface products, including images of vegetation indices (VI), is derived from the Moderate Resolution Imaging Spectroradiometer (MODIS) sensor since 2000. This paper reports the development of the Temporal Vegetation Analysis System (SATVeg), a free web-based tool designed to provide instantaneous access to temporal profiles of MODIS VI in South America. The system's architecture is based on a geospatial database specially modeled to store the time series of images and ensure instantaneous queries and efficient updating. The results of the geospatial database modelling and respective response time for queries and updates, as well as the main functionalities of the system, are presented and discussed. Instantaneous reconstruction of time series provided by a set of filtering procedures is also related. Application examples of VI temporal profiles generated by SATVeg are presented and the system's limitations are also discussed. Our results show the potential of the web-system for supporting a set of land use and land cover monitoring activities in South America through a simple and friendly user interface.