Why is the Atlantic storm track stronger than its Pacific counterpart?
Edmund K. M. Chang, Stony Brook University, Stony Brook, NY; and W. Lin One puzzle confronting atmospheric dynamicists is why during the Northern Hemisphere (NH) mid-winter, the Atlantic storm track is stronger than its Pacific counterpart. This is puzzling because the upper level jet and low level baroclinicity are much stronger over the Pacific storm track entrance region. In this study, a dry global circulation model is used to examine the contributions made by orographic and diabatic forcings in shaping the zonal asymmetries of the NH winter storm tracks. By design, the model mean flow is forced to bear a close resemblance to the observed zonal mean and stationary waves. The model also provides a decent simulation of the storm tracks. In particular, the maxima over the Pacific and Atlantic, and minima over Asia and North America, are fairly well simulated. The model also successfully simulates the observation that the Atlantic storm track is stronger than the Pacific storm track. S
