Refinements in the use of equivalent latitude for assimilating sporadic inhomogeneous stratospheric tracer observations, 2: Precise altitude-resolved information about transport of Pinatubo aerosol to very high latitude

[摘要] From high latitude lidar observations, quite precise informationis extracted about the temporal evolution and vertical distribution of volcanic aerosol in the highlatitude lower stratosphere following the eruptionof Mount Pinatubo.Irreversible mixing of lower stratosphericaerosol, to the arctic pole during early 1992, is demonstrated, as afunction of potential temperature and time.This workcomplements previous studies, which either identify vortex intrusions - without demonstratingirreversible transport, or use lower resolution satellite observations.The observed transport is associated tentatively with the vortexdisturbance during late January, 1992.A very large number of highresolution lidar observations of Mount Pinatubo aerosol are analysed,without any data averaging.Averaging in measurement or analysis cancause tracer mixing to be overestimated.Averaging in the analysiscan also require assumptions about which quantity has the dominanterror (in this case, the equivalent latitude coordinate or themeasurement), and which part of the data contains real structure.Themethod below attempts to avoid such assumptions.

[学科分类] 大气科学