[1] Ten years of high-resolution radiosonde data are contrasted with fifteen years of ECMWF reanalysis (ERA) data to explore the tropopause region above two midlatitude stations (Munich and Stuttgart) in Southern Germany. We present time-averaged vertical profiles of several meteorological parameters relative to the tropopause. A strong mean inversion at the tropopause is evident from the radio...

A new tropopause definition involving a flow-dependent blending of the traditional thermal tropopause with one based on potential vorticity has been developed and applied to the European Centre for Medium-Range Weather Forecasts (ECMWF) reanalyses (ERA), ERA-40 and ERA-Interim. Global and regional trends in tropopause characteristics for annual and solsticial seasonal means are presented here, ...

A cold air outbreak (CAO) is an extreme weather phenomenon that has significant social and economic impacts over a large region of the midlatitudes. However, dynamical mechanism occurrence evolution CAO events, particularly role stratosphere, not well understood. Through analysis one episode occurred on 27–31 January 2019 across much US Midwest, this study examined its thermodynamic structure i...

The evolution of the tropopause in the past, present, and future climate is examined by analyzing a set of long-term integrations with stratosphere-resolving chemistry climate models (CCMs). These CCMs have high vertical resolution near the tropopause, a model top located in the mesosphere or above, and, most important, fully interactive stratospheric chemistry. Using such CCM integrations, it ...

A new tropopause definition, based on a flow-dependent blending of the traditional thermal tropopause with one based on potential vorticity, has been developed. The benefits of such a blending algorithm are most apparent in regions with synoptic scale fluctuations between tropical and extratropical airmasses. The properties of the local airmass determine the relative contributions to the locati...

Using the MST radar data of vertical wind, the characteristics of the tropical tropopause, following four different definitions, depending on 1) temperature lapse rate, 2) cold point, 3) convective outflow and 4) potential temperature lapse rate minimum, are studied. From the vertical wind data of the radar, the altitude profiles of temperature and horizontal divergence are derived, from which ...

Stratosphere-troposphere exchange could be enhanced by tropopause folding, linked to variability in the subtropical jet stream. Relevant to tropospheric biogeochemistry is irreversible transport from the stratosphere, associated with deep intrusions. Here, oxygen anomalies in near surface air CO2 are used to study the irreversible transport from the stratosphere, where the triple oxygen isotope...

The sensitivity of the tropopause height to various external parameters has been investigated using a global circulation model (GCM). The tropopause height was found to be strongly sensitive to the temperature at the earth’s surface, less sensitive to the ozone distribution, and hardly sensitive at all to moderate changes in the earth’s rotation rate. The strong sensitivity to surface temperatu...