The U.S. contribution to

Climate Variability and Predictability

African Monsoon Multidisciplinary Analyses

To improve the forecasting of the African monsoon from weather to climatic scales a sound disciplinary knowledge of the processes and their scale dependence is needed. With the intensive field campaign, AMMA will provide the data needed to test hypotheses on tropical weather systems, their interaction with large scale dynamics, aerosol processes and their role in chemical transports. The observations over the continents and oceans will help to advance our understanding of the links between hydrological and biological processes over land and the air-sea interactions over the tropical Atlantic ocean.

Towards achieving improved seasonal-to-interannual predictions our knowledge of the interactions between the monsoon and the slower and larger scale components of the climate system must be advanced. The monitoring of the water cycle put into place within AMMA will lay the grounds for improving our understanding of the characteristics of the inter-annual rainfall variability. This will help assess predictive skill held in the slow evolution of sea surface temperatures and/or land-surface states. A deeper multidisciplinary understanding of the interactions between the monsoon and the global climate from a physical as well as a chemical perspective will increase our confidence in the predicted climate change over the region.

It is AMMA’s aim to provide the African decision makers with improved assessments of similar rainfall changes which are likely to occur during the 21st century due to natural fluctuations and as a result of anticipated global climate change. An essential step in that direction is to improve our ability to forecast the weather and climate in the West African region.

AMMA has 3 main goals :

• to improve understanding of the West African Monsoon and its influence on the physical, chemical and biological environment, regionally and globally.
• to provide the underpinning science that relates variability of the WAM to issues of health, water resources, food security and demography for West African nations and defining and implementing relavent monitoring and prediction strategies.
• to ensure that the multidisciplinary research carried out in AMMA is effectively integrated with prediction and decision making activity

The AMMA homepage can be found at : www.amma-international.org