Dynamics of tropical atmosphere

Tropical circulations like monsoons and tropical cyclones depend on convection which corresponds to the movement of air masses leading to clouds formation. We study the life cycle and spatial organization of the convection following complementary approaches: development of theories, development of parameterizations in global atmospheric models but also development of instruments and participations in field campaigns.

Development of boundary-layer balloons

The team is developing quasi-Lagrangian balloons, called Aeroclippers, to study air-sea interactions in the tropical boundary layer. In particular, the Aeroclipper will allow to measure key atmospheric variables (temperature, pressure, humidity and winds) at high frequency (1 minute) within the eye of tropical cyclones. Several field campaigns organized in Guam Island in 2022 and 2023 have validated the concept, one of the deployed balloons having lasted 23 days.


Identification and characterization of convective processes at small scales  (thermals, breeze, or squall lines) and their interactions with the surface and large-scale background flow are studied using Large Eddy Simulations (LES) and Cloud Resolving Models (CRM) where convection is explicitly resolved. Idealized setups of LES and CRM models are particularly useful to study the aggregation of convection and the formation of tropical storms.


Convective precipitation associated with western African monsoon is studied to better understand dynamical processes leading to regional precipitation variability in western Africa. The role of the ocean, greenhouse gas, and sulfate aerosols in such variability are more particularly investigated. Extreme precipitation and their links with mesoscale convective systems are more generally studied over the whole tropical band using kilometer-scale models.

Permanent Staff

H. Bellenger, H. Chepfer, J.-P. Duvel, B. Fildier, M. Ghil, A. Giannini

PhD students, postdocs

M. Carenso, L. Parc