Super typhoon Haiyan makes landfall
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Lake Maggiore - Italy, 3-6 April 2000

Monitoring natural disasters and "hot spots" of land-cover change with SPOT VEGETATION data to assess regions at risk and vulnerability

Prof. E. F. Lambin, Dr. I. Reginster & F. Lupo Sartor
Department of Geography
Universite catholique de Louvain place Louis Pasteur, 3
B-1348 Louvain-la-Neuve, Belgium

Paper (pdf file, 519 k)

All recent scientific evidences clearly point to the fact that the impact of global change on land surface attributes will not be uniformly distributed geographically. Assessing the regions "at risk" of rapid land-cover changes and/or natural disasters is therefore a priority for global change research and for policies aimed at mitigating the impact of these changes. The objectives of this project are to: (1) Use SPOT VEGETATION data to monitor over large regions the impact on ecosystems of natural disasters such as droughts, fires, floods and vegetation diseases, as well as land-cover change ‘hot spots’; (2) Validate and interpret SPOT VEGETATION-based maps of natural disasters and extreme land-cover changes with collateral data on natural disasters and ‘hot spots’ of land-cover change; (3) Integrate this validated product in the current efforts of the global change scientific community, sponsored by the International Geosphere-Biosphere Programme (IGBP) and International Human Dimensions Programme on Global Environmental Change (IHDP), to assess regions ‘at risk’ of rapid environmental change in order to focus research on most vulnerable areas and support the design of appropriate mitigation policies.

The product can only be generated once two full years of SPOT VEGETATION data will be acquired (i.e. by April 2000). In the meantime, a data processing chain with the change analysis algorithm has been designed, and initial tests over two growing seasons in West Africa (June to November 1998 and 1999) have been conducted. Through these tests, we evaluated the level of data pre-processing required (i.e. geometric registration, compositing period and criteria, combination of spectral bands) to detect different processes of land-cover change. We also evaluated whether the change detection algorithm needs to be adapted to different situations and different biomes. In parrallel, we are assembling a database of collateral data on natural disasters and rapid land-cover changes during the period April 1998-April 2000 for validation and interpretation of the VEGETATION-based change maps.

Our first result include a map (available in digital format) which represents the impact of the natural disasters and rapid land-cover changes which have occurred during the growing seasons of 1998 and 1999 in West Africa. For every 'hot spot' of change detected (flooding, decrease or increase in vegetation cover), we have compiled information on the type of change, their cause (exceptional rain events, drought conditions, migratory pests or fires) and their environmental significance.

While the ultimate objective of the project is to generate a product at a global scale, during the first year, we are only processing data over the whole of Europe and Africa. The main end-users of this project are the International Geosphere-Biosphere Programme (IGBP) and International Human Dimensions Programme on Global Environmental Change (IHDP), for the cross-cutting activity on "Vulnerability and regions at risk". Moreover, the project provides a geographic product for the concluding year of the International Decade for Natural Disaster Reduction (IDNDR), sponsored by the United Nations.