Accueil > ENVISTORM (2006-2009) : Role of the environment (humidity and deformation) in the life cycle and variability of winter storms

ENVISTORM (2006-2009) : Role of the environment (humidity and deformation) in the life cycle and variability of winter storms

ENVISTORM is a collaborative project between the "Laboratoire de Météorologie Dynamique" (LMD) and "le Groupe de Recherches sur l’Atmosphere Météorologique" (CNRM  -GAME). It is devoted to studying the life cycle of extratropical cyclones. One of the major challenges of modern meteorology concerns the assessment of frequency and amplitude of extreme events such as mid-latitude storms, as well as their predictability. This issue is all the more relevant in the context of climate changes through the societal impacts of damages caused by these extreme events (such as the Christmas 1999 storms). Therefore, the use and development of new theoretical tools are needed to better predict their characteristics in global change.

This project objective is to identify and characterize the factors that precondition the mid-latitude winter storms and that modify their strength and variability at the intra-seasonal time-scale. In particular, we will examine how the life-cycle of atmospheric perturbations depends on its large-scale environment (that tends to channel the storms through the deformation field) and by water vapor (that tends to intensify the storms through latent heat release associated with large-scale precipitation). These two processes have an impact not only on storms development but also on their interaction with the large-scale flow and with resulting weather regimes. A better understanding of these processes will allow to anticipate the evolution of these storms in the future climate and to improve their short-range forecasts.