A statistical analysis of vertical shear effect on tropical cyclone intensity change in the North Atlantic

[1] Based on the best track data of tropical cyclones (TCs) in the North Atlantic and the NCEP/NCAR reanalysis during 1981–2008,the effect of vertical wind shear (VWS) between different vertical levels and with different directions of shear on TC intensity change for TCs of different intensities, translational speeds, and latitudes were statistically analyzed. The results show that TC intensity change and VWS are generally negatively correlated, indicating the overall negative effect of VWS on TC intensity. The strong, slow moving, and low latitude TCs are strongly affected by VWS in a deep layer, while the weak, fast moving, and high latitude TCs are subject to strong effect by VWS in the mid-lower troposphere. Furthermore, overall easterly shear, especially in the mid-lower troposphere, has considerably weaker effects on TC intensity change than westerly shear because part of the easterly shear could be offset by the beta-induced northwesterly shear. Citation: Zeng, Z., Y. Wang, and L. Chen (2010), A statistical analysis of vertical shear effect on tropical cyclone intensity change in the North Atlantic, Geophys. Res. Lett., 37, L02802, doi:10.1029/2009GL041788.