She works for the French space agency CNES and has been deputy director of the Laboratoire d'Etudes en Geophysique et Oceanographie Spatiales [fr] (LEGOS) at Observatoire Midi-Pyrénées in Toulouse since 1996.
Cazenave is a member of the Intergovernmental Panel on Climate Change and was the lead author of the sea level sections for their fourth and fifth Assessment Reports.
She used satellite altimetry data from SEASAT, ERS-1, and TOPEX/Poseidon to devise gravity models of deep ocean geodynamic processes.
The models were used to investigate marine tectonic features such as geoid height variations across deep ocean trenches and fracture zones, lithospheric cooling and subsidence, and the isostatic compensation of seamount chains.
She addressed the problem of balancing the global sea level budget by incorporating time-dependent gravity field data from the GRACE satellite system into her analyses.