AMMA-CATCH observatory: Niamey square degree mesoscale site (16 000 km2) in the cultivated Sahelian zone, Niger

The Niger mesoscale observation site is geographically central among the three such sites of the AMMA-CATCH regional observatory. Located 13-14°N and 2-3°E in SW Niger, it samples the cultivated Sahelian environment, on both sides of the Niger River albeit predominantly to its north-east, and includes the city of Niamey. The climate is semiarid, with ~300-700 mm/year of rainfall concentrated in a short monsoon season (July-September essentially). Landuse is a patchwork of millet fields, fallow bush plots, tiger bush, and bare land. Meteorological, hydrological, and ecological observations have been carried out for several decades at this site, starting with the EPSAT-Niger, HAPEX-Sahel, SEBEX programs in the 80-90's. Most instruments were made perennial since the launch of the AMMA international experiment in 2005.