Measuring the loss of evergreen forest cover in protected areas as well as deforestation in forest- rich countries such as those in Latin America has played a crucial role in climate change mitigation. How can forest cover change be measured? The use of nearly real-time remote sensing is an effective tool for detecting shifts in forest canopies and identifying protection levels.
An international team of geographers and conservationists has developed a system, Terra-i, to monitor deforestation across Latin America in near real-time using satellite data. It uses data from the Moderate-Resolution Imaging Spectroradiomete (MODIS) sensor on NASA’s Terra and Aqua platforms and Normalized Difference Vegetation Index (NDVI) for spatial analysis and comparison of vegetation changes based on the spectral response of the vegetation cover surface.
The Terra-i approach centres on a forecasting model that is capable of predicting the evolution of vegetation for a site which it fathoms based on the relationship between a location's previous foliage measurements and climate data. When major changes in the vegetation index are detected that lie outside of the usual pattern of seasonal evolution, it is assumed that they are due to human interventions that have impacts on natural ecosystem, such as illegal logging activities. These events are, therefore, flagged in near-real time as events that land managers, conservationists, and policy makers should be aware of.
"Achieving the right balance between intelligently intensive agriculture and protected natural environments across the world will be fundamental to achieving truly sustainable development and requires sophisticated, geographically detailed and timely tools such as Terra-i to support appropriate policy and decision-making." - Mark Mulligan, Professor from Department of Geography at King's College London
Example from Terra-i YouTube channel
It provides maps, images and analyses of habitat change every 16 days for every 250 metres on the ground. The data is shared for free and people can visualise the data within a geobrowser (web map) or download the Geographical Information Systems (GIS) files for further analysis. The software can now be used offline (i.e. in the field) from an Android smartphone or tablet computer. It aims at helping national governments, conservationists and those implementing climate-related policy to assess trends in deforestation in Latin American countries. One drawback is that because MODIS sensor resolution is relatively low (250-m), small-scale events are more difficult to detect.
The project was initiated by a PhD student at King's College London. It then later became an international project run by the International Centre for Tropical Agriculture (CIAT) in collaboration with The Nature Conservancy, HEIG-VD (Haute Ecole d'Ingénierie et de Gestion du Canton de Vaud) and King's College London.