A prototype regional Drought Monitoring System (DMS) for South-West Asia was developed in 2004 with funding from the US State Department Regional Environment Office for South Asia. It was meant to serve as an illustration of capabilities provided by remote sensing data for drought monitoring and as an example that may be replicated (and developed further) in other regions.
The system uses an on-line remote sensing database to monitor drought development through continuous assessment of the condition of ground vegetation. It operates at the fine level of spatial resolution (0.5 km X 0.5 km) and in near-real time, whereby new data can be added every 8 or 16 days.
Users of the system can:
- Explore the spatial condition of ground vegetation throughout south-west Asia region, at the level of specific districts in respective countries and at the level of specific pixels of 0.5 by 0.5 km. The default spatial image shows the distribution of NDVI over a district, sub-district administrative boundaries if any exist and some landmarks, including rivers/canals, roads and or settlements. A similar approach is followed for other drought indices.
- Create the on-line time-series graphs of drought-related vegetation characteristics and study the deviation of those from the long-term mean for a district or pixel. The graphs can be built for a time period selected by the user, allowing the developing deficits of vegetation density and vigor to be detected and quantified on-line. Once the district is selected on the front page of the DMS, the default time series graph appears showing the long-term average NDVI and the current NDVI time series. The start of the plotting period can be interactively selected at this point and the time series graph re-plotted. Similarly, other indices can be examined at this stage by clicking the appropriate link on the screen and accessing the on-line database.
- Download images of vegetation indices for selected districts/provinces for inclusion in various reports or presentations. These images may be previewed before downloading.
- Learn about the use of remote sensing data and indices for drought monitoring as well as about system operation through on-line Help facilities.
- Link to other drought monitoring web sites
Drought monitoring systems like this, can now be developed with even more resolute RS data. It is envisaged that such systems could benefit government agencies, research institutions and NGOs involved in drought management and may be a valuable addition to decision support tools. Additional developments of such systems may include the use of other datasets (rainfall, temperature), many other drought-related indices, provision of targeted warning messages that suit specific requirements of individual countries, etc. This calls for collaborative action and for input from relevant national agencies. The principles, on which the system is based, are generic and can be reproduced nationally, or regionally.
The details of the methodology behind the DMS are described in IWMI Research Report 85.