Investigation of processes driving low level westerlies in central Africa
Wilfried Mba's CSRP research focuses on the low level circulation in Central Africa.
Low level westerlies from the Atlantic Ocean drive significant low level moisture advection in central Africa throughout the year, but mainly during the big rainy season (September to November, SON). This low level moisture from Atlantic Ocean modulates the entire atmospheric column moisture variability.
Very little is known about the processes which control the height of these low level westerlies, the seasonal and interannual variability of their strength, or how they are maintained throughout the year.
This study will also explore teleconnection mechanisms between the low level circulation and the anticyclone of Saint Helene, the Benguela current, the low level jet along the Namibian coast and El Niño events. Diagnostic analysis of Met Office PRECIS simulations will be done to evaluate the representation of all above processes and interactions.
Wilfried Mba's research interests have included the study of atmospheric thermodynamics in Central Africa. The aim of this study was to describe the thermodynamic structure of the atmosphere in central Africa.
His interest now is to follow this up by identifying keys processes at the base of climate variability in central Africa, mainly in the atmospheric water cycle, and analyse their representations in simulations of GCMs to assess the impact on climate change. The study underway focuses on water vapour transport and precipitation recycling for Equatorial Central Africa, using NCEP Reanalysis data. The study emphasizes the seasonal cycle and interannual variability of the water vapour flux and precipitation recycling with discussions to identify the dominant regulating factors of this variability. These processes are important for understanding basic precipitation generation mechanisms and their seasonal and annual and longer term variation from the point of view of the large scale water vapour sources.
He has also run the regional climate model PRECIS for downscaling purposes over central Africa. Through domain size sensitivity experiments, an optimum domain was identified. Experiments were conduct to study the impact of future climate change in Central Africa.
Areas of particular interest and expertise:
This research project aligns with CSRP Theme 2: Investigation of the mechanisms underlying climate variability.
Wilfried Mba is working in collaboration with Rob Chadwick and Caroline Bain of the Met Office.
Last updated: 12 May 2016