relatively weak threshold allows the detection of TDVs at an early stage, but stronger TC-like systems have a too large TDV area at with ill-defined characteristics. The is thus TDV area  computed for a series of deeper thresholds (i.e., < -80m2s-2) and the first threshold giving an equivalent radius of the TDV area lower than 3° of latitude-longitude is retained. For developed cyclones, this threshold may be less than -1200m2s-2. The tracking of a TDV is performed by considering the overlap between TDV areas in two consecutive time steps. If several TDVs are overlapping, only the TDV with the largest overlap is considered for the continuity of the tracking. Each TDV is thus represented by time series for its location and for other characteristics of the TDV area (maximum surface wind, maximum vorticity at 850hPa, maximum geopotential perturbation minimum surface pressure, etc.). , Here, since we are mostly interested in simulation of the TC activity over the North Atlantic Ocean, we only consider TDVs that are initiated south of 40°N and that spend at least two days over the tropical North Atlantic waters. These TDVs are called Atlantic TDVs, or simply TDVs here. This means that TDVs that initiate over West Africa but dissipate before reaching the Atlantic are not considered. In fact, some TDVs initiated over West Africa near the eastern side of the zoom (see Fig.1) are partly forced by the nudging toward ERA-I. However, the dissipation or maintenance of these TDVs as they propagate westward toward the African west coast and over the Atlantic is fully determined by the LMDZ model. The strength of a TDV is characterized by Accumulated Cyclone Energy (ACE) computed on the basis of the maximum surface wind vmax in the TDV area at each time step. The values in the model are not directly comparable to the observed ACE since the maximum surface wind
relatively weak threshold allows the detection of TDVs at an early stage, but stronger TC-like systems have a too large TDV area at  with ill-defined characteristics. The TDV area is thus computed for a series of deeper thresholds (i.e., < -80m2s-2) and the first threshold giving an equivalent radius of the TDV area lower than 3° of latitude-longitude is retained. For developed cyclones, this threshold may be less than -1200m2s-2. The tracking of a TDV is performed by considering the overlap between TDV areas in two consecutive time steps. If several TDVs are overlapping, only the TDV with the largest overlap is considered for the continuity of the tracking. Each TDV is thus represented by time series for its location and for other characteristics of the TDV area (maximum surface wind, maximum vorticity at 850hPa, maximum geopotential perturbation , minimum surface pressure, etc.). Here, since we are mostly interested in simulation of the TC activity over the North Atlantic Ocean, we only consider TDVs that are initiated south of 40°N and that spend at least two days over the tropical North Atlantic waters. These TDVs are called Atlantic TDVs, or simply TDVs here. This means that TDVs that initiate over West Africa but dissipate before reaching the Atlantic are not considered. In fact, some TDVs initiated over West Africa near the eastern side of the zoom (see Fig.1) are partly forced by the nudging toward ERA-I. However, the dissipation or maintenance of these TDVs as they propagate westward toward the African west coast and over the Atlantic is fully determined by the LMDZ model. The strength of a TDV is characterized by Accumulated Cyclone Energy (ACE) computed on the basis of the maximum surface wind vmax in the TDV area at each time step. The values in the model are not directly comparable to the observed ACE since the maximum surface wind