On the accuracy of different types of trajectories

摘要

Long-range transport processes are often investigated by calculating air mass trajectories or multiple particle trajectories. Several alternative calculation techniques are currently in use, sometimes producing significantly different results. It is not possible to determine which of the trajectories are most accurate with-out using a tracer that is conserved along the real three-dimensional trajectories. Here, conservative meteorological quantities, potential vorticity, specific humidity and potential temperature, are used as tracers. As these tracers are conserved only in the absence of diabatic processes, regions of the atmosphere where these processes are most important are excluded. Tracer conservation aloong six different types of trajectories is studied.