The JET2000 project: aircraft observations of the African easterly jet and African easterly waves

摘要

The JET2000 aircraft campaign in West Africa is introduced along with preliminary analysis of the anomalous dry conditions that characterized the campaign, the African easterly jet, easterly waves, and numerical weather prediction data denial experiments. West Africa is a region that experiences marked interannual variability of rainfall (e.g., Rowell et al. 1995). This impacts water resources, agriculture, and health, sometimes resulting in extreme social and economic problems and loss of life. West African climate variability also impacts the downstream tropical Atlantic by influencing hurri-cane activity (e.g., Landsea and Gray 1992). Because of the marked variability and associated impacts there is a clear need for skillful medium to seasonalrange predictions of rainfall and other variables for the West African region. There is also a need for increased confidence in predicted climate change scenarios for the region. The hydrologkal cycle in West Africa shows a large sensitivity to projectedclimate change scenarios and this at a time when water resources will come under intense pressure from a fast-increasing population (McCarthy et al. 2001).