Empirical age spectra for the midlatitude lower stratosphere from in situ observations of CO2: quantitative evidence for a subtropical "barrier" to horizontal transport

Andrews, A.E., K.A. Boering, S. Wofsy, B.C. Daube, D.B. Jones, S. Alex, M. Loewenstein, J.R. Podolske, and S. Strahan (2001), Empirical age spectra for the midlatitude lower stratosphere from in situ observations of CO2: quantitative evidence for a subtropical "barrier" to horizontal transport, J. Geophys. Res., 106, 10257-10274.