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29 Aug 2017 description
map UNOSAT

This map illustrates the satellite-detected surface waters extent and evolution over Niamey and surroundings in Niger as observed from the Sentinel-1 images acquired on 14 and 26 August 2017. Within the analysed area, an increase of surface waters extent was observed from the 26 August 2017 image: ~7,870 ha of surface water were observed the 14 August 2017 and reached ~10,210 ha the 26 August 2017. All over the analysed zone, it corresponds to an evolution of about 30%.

06 Nov 2013 description
map UNOSAT

This map indicates small temporary water bodies, wetlands, and other humid areas as measured every 10 days between 1999 and the 31 October 2013 by SPOT satellites. Each pixel therefore indicates how many decadal (ten day) periods within the 178 month sampling period experienced some form of inundation or wetland conditions. Darker pixels indicates areas with relatively higher frequency of inundation, while lighter pixels indicate areas with less frequent inundations.

05 Dec 2012 description

This map illustrates satellite-detected probable extent of flood water evolution in the City of Diffa and surrounding areas in Niger as of 02 December, 2012. For extracting the initial flood water extent a MODIS Terra image of 11 November 2012 was used and for extracting the recent flood water extent a MODIS Aqua Image of 02 December, 2012 was used.

09 Sep 2009 description

This map illustrates satellite-detected changes in the flood water levels in the Agadez Region of Niger, as based on change detection methods using MODIS Aqua data acquired over the area on 3, 5 & 7 September and 11 August 2009. There are 3 water classes identified in the map: where waters have increased (red), decreased (green) and remained static (yellow) from 3 to 7 September. The majority of water in the area has receded rapidly, however there is some minor new water flow to the north. The newly released ASTER global elevation model (GDEM) was also used in this analysis.

18 Sep 2007 description

This map illustrates the total August rainfall accumulation for East Africa, derived from the CMORPH precipitation dataset at a spatial resolution of approximately 10km for this region, and was calculated using microwave and infrared data from geostationary satellites. It is possible that precipitation levels may have been underestimated for local areas, and is not a substitute for ground station measurements.

16 Sep 2007 description

This map illustrates the total August rainfall accumulation for West Africa, derived from the CMORPH precipitation dataset at a spatial resolution of approximately 10km for this region, and was calculated using microwave and infrared data from geostationary satellites. It is possible that precipitation levels may have been underestimated for local areas, and is not a substitute for ground station measurements.