Climate-related impacts on food security and water availability continue to affect many parts of the globe. Several regions, including sub-Saharan Africa, are not only susceptible to these impacts, but also lack the ability to monitor climate-related risk. Earth observation (EO) satellites have been instrumental in offering large-scale monitoring capabilities for analysis of rainfall, evapotranspiration, vegetation condition, soil moisture, and other agro-climatological factors that impact food and water security in these data-sparse regions. The USGS and colleagues at the University of California Santa Barbara Climate Hazards Center have developed the Early Warning eXplorer (EWX) tool to address these regional monitoring limitations by providing easy access to and analysis of EO information in support of the U.S. Agency for International Development Famine Early Warning Systems Network (USAID FEWS NET).
The EWX implementation is based on three primary components. The first is the EWX Viewer, which is accessible via an internet browser and offers the ability to visualize various datasets in map form and to derive time series summaries for desired spatial domains (such as administrative units and crop zones). In addition to visualization and analysis, the viewer also provides the ability to download gridded data for specified subset areas. The second component is the GeoEngine processing server, which is at the heart of the EWX system. It provides web services, the graphical user interface, file system management, and time series analysis, as well as storage and retrieval of outputs to and from the EWX database. The third component, Support Applications, includes a map server, GeoServer instance, and a PostgreSQL database for managing statistics and file systems, all while routinely monitoring for new and/or modified EO inputs from various FEWS NET science sources.
Major strides have been made in terms of development and real-time availability of remote sensing based EOs; however, access to those datasets and their applications for informed decision making is limited. The EWX is a web service that aims to both fill the in situ data gap and facilitate application of EO information for decision making to support mitigating the most adverse impacts of climate extreme events and climate adaptation.
Flowchart of the main components of the Early Warning eXplorer.