Erwan Monier

Postdoctoral Associate

Joint Program on the Science and Policy of Global Change

Center for Global Change Science

Research

Intraseasonal Variability

I use the mesoscale regional model MM5 to investigate the Madden-Julian Oscillation wind-convection coupling and the role of moisture processes. A significant finding is the ability of the model to simulate a realistic MJO phase speed in the winds without reproducing the MJO wind-convection coupling or a realistic propagation in the free atmosphere water vapor. This study suggests that the convergence of boundary layer moisture and the discharge and recharge of the moist static energy and atmospheric instability may be responsible for controlling the speed of propagation of the MJO circulation and that deep convection is not a fundamental feature controlling the speed of propagation of the MJO in the winds but simply a by-product of the MJO.

Article:

Monier, E., B. C. Weare, and W. I. Gustafson Jr., 2009: The Madden-Julian oscillation wind-convection coupling and the role of moisture processes in the MM5 model. Climate Dynamics. In press, doi:10.1007/s00382-009-0626-4.

Climate Dynamics

My research on climate dynamics includes a climatology and trend analysis of the wave forcing of the stratospheric zonal-mean flow based on the calculation of the momentum budget using the Transformed Eulerian-Mean (TEM) framework and the six-hourly ECMWF ERA-40 re-analysis. This study reveals that the dissipative forcing term, calculated as the residual term in the momentum equation, exhibits obvious characteristics of a gravity wave drag and contributes considerably to driving the Brewer-Dobson circulation and decelerating the polar vortex. Also, the trend analysis shows a delay of the breakdown the polar vortex in both hemispheres due to a decrease in wave activity.

Article (in preparation):

Climatology and Trends in the Wave Forcing of the Stratospheric Zonal-Mean Flow. In collaboration with: Bryan C. Weare.

Chemical Transport

My research on this topic focuses on the role of dynamical transport on the climatology and trends of the stratospheric ozone. This study outlines the considerable contribution of ozone eddy transport to the Antarctica ozone hole recovery and, in particular, large trends in the ozone mixing balancing equally large trends in the chemical destruction of ozone in October and November.

Article (in preparation):

Climatology and Trends in the Wave Forcing of the Stratospheric Ozone Transport. In collaboration with: Bryan C. Weare.