Zonal wind variability and Sahel rainfall: 20th and 21st century
By identifying relationships between rainfall and the variability of large-scale fields that are resolved in climate models (i.e. zonal wind), we hope to side step issues caused by rainfall parameterization. Furthermore, by considering the entire troposphere, our analysis captures the complex interaction between a number of phenomena linked to rainfall (the Tropical Easterly Jet, African Easterly Jet and monsoonal westerlies). Using robust modes of zonal wind variability, we then assess how these patterns are represented in the CMIP5 model runs. This allows us to investigate whether model deficiencies, or true disagreements in future forcing, explains the divergence of rainfall projections.