AMMA - AFRICAN MONSOON MULTIDISCIPLINARY ANALYSIS

The dramatic change in the region of the West African monsoon (WAM) from wet conditions in the 50s and 60s to much drier conditions from the 70s to the 90s represents one of the strongest inter-decadal signals on the planet in the 20th century. Marked inter-annual variations in recent decades have resulted in extremely dry years with devastating environmental and socio-economic impacts. The abrupt decrease of water resources in the Sahel divided by two the cattle population and some exportation cultures disappeared. Vulnerability of West African societies to climate variability is likely to increase in the next decades as demands on resources increase due to the rapidly growing population. The situation may be exacerbated by the effects of climate change, land degradation caused by the growing population and water pollution. Motivated by the need to develop strategies to reduce the socioeconomic impacts of climate variability and change in WAM we aim : i) To improve our ability to predict the WAM and its impacts on intra-seasonal to decadal timescales, ii) To improve our ability to predict the consequences of climate change on WAM variability and its impacts.
These objectives will be achieved in the African Monsoon Multidisciplinar/ Analysis (AMMA) project by re-enforcing the regional environmental monitoring systems and conducting intensive field campaigns.This will lead to a better understanding of the mechanisms involved and in-fine improve our models and their predictive skills. The observational system will cover the regional water cycle, the atmospheric dynamics and chemistry, the land-surface and oceanic conditions. It will cover 3 time scales : i) a long term monitoring, ii) an enhanced observing period of two years and iii) a special observing periods over one rainy season. In order to monitor the human dimension of the West African monsoon variability crop yields, water resources and health will be monitored with the same strategy.