Geostatistical Analysis and Numerical Simulation of West African Sahel Rainfall

摘要: The pattern of rainfall in the Sahelian zone West Africa has been subject much analysis since major droughts 1970s. It is widely accepted that annual declined time and it a regional trend. rain gauge network changed during this recent period desiccation. Since region now recognised as not being homogeneous, there some doubt about reliability aggregated statistics. This uses geostatistics to investigate impact changes 1931 numerical simulations an attempt validate results. approach can include most records, unlike conventional methods. seems configuration stations E-W direction accounted for spatial variation better 1970s because eastward extension stations. N-S do sample adequately generally large between ca. 1945 1975. only when distribution both directions was adequate 1970. Thus, results suggest persistent downward trend return more accurate estimate region; prior overestimated. statistics artifact location rainfall. Regional maps (total summer) are based on geostatistical which takes account These believed be reliable than those interpolation approaches form basis revised median west African Sahel 1990.