Abstract
Taking advantage of multiple new remote sensing data sources, especially from Chinese satellites, the CropWatch system has expanded the scope of its international analyses through the development of new indicators and an upgraded operational methodology. The approach adopts a hierarchical system covering four spatial levels of detail: global, regional, national (thirty-one key countries including China) and “sub-countries” (for the nine largest countries). The thirty-one countries encompass more that 80% of both production and exports of maize, rice, soybean and wheat. The methodology resorts to climatic and remote sensing indicators at different scales. The global patterns of crop environmental growing conditions are first analyzed with indicators for rainfall, temperature, photosynthetically active radiation (PAR) as well as potential biomass. At the regional scale, the indicators pay more attention to crops and include Vegetation Health Index (VHI), Vegetation Condition Index (VCI), Cropped Arable Land Fraction (CALF) as well as Cropping Intensity (CI). Together, they characterize crop situation, farming intensity and stress. CropWatch carries out detailed crop condition analyses at the national scale with a comprehensive array of variables and indicators. The Normalized Difference Vegetation Index (NDVI), cropped areas and crop conditions are integrated to derive food production estimates. For the nine largest countries, CropWatch zooms into the sub-national units to acquire detailed information on crop condition and production by including new indicators (e.g., Crop type proportion). Based on trend analysis, CropWatch also issues crop production supply outlooks, covering both long-term variations and short-term dynamic changes in key food exporters and importers. The hierarchical approach adopted by CropWatch is the basis of the analyses of climatic and crop conditions assessments published in the quarterly “CropWatch bulletin” which provides accurate and timely information essential to food producers, traders and consumers.
Highlights
Food security is one of the most basic factors of our physical and intellectual wellbeing
This paper describes a hierarchical method of global crop monitoring that takes advantage of the significant progress of satellite remote sensing and products, as adopted in the recently upgraded
Vegetation Health Index (VHI) is an effective indication of the crop stress which is calculated by averaging the Vegetation Condition Index (VCI) [53] and Temperature Condition Index (TCI)
Summary
Food security is one of the most basic factors of our physical and intellectual wellbeing. In order to collect relevant data and to gain firsthand knowledge about the domestic and international agricultural situations, many countries and institutions around the world have developed dedicated agriculture monitoring systems [1] by complementing their traditional ground-based approach with satellite remote sensing based inputs Their objective is mostly to ensure national food security by shielding domestic market and production from the vagaries of international markets. The size differences between countries and the spatial variation of agrometeorological variables within countries are seldom considered; the methodology applied in crop monitoring systems is often obsolete, and production estimation is the main output, which provides little early warning information. The new hierarchical approach ensures that analyses look at large features before zooming into details
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
