Abstract:

The Congo Basin, home to the world’s second-largest tropical rainforest and a key global precipitation center, is among the least studied region in the tropics with virtually no long-term in-situ data and relatively underdeveloped infrastructure for research. Existing research suggests that the mechanisms that control its seasonal rainfall are more complex than Amazon and unique to the region. Using remotely-sensed water vapor isotopes, I first clarify whether evapotranspiration or advected oceanic moisture contributes more to atmospheric moisture for rainfall in the Congo Basin. Then, I investigate the complex interactions between large-scale atmospheric circulations and moisture sources and how they work together to condition the atmosphere to support deep convection during those transition periods. I investigate the southern Congo and equatorial Congo separately to account for differences in their seasonal rainfall regimes, with future work involving investigating the northern Congo. This work thus provides the first comprehensive assessment on the processes controlling the dry to wet season transition periods in the Congo.