Spatial and temporal distribution of stratospheric turbulence from global high-resolution radiosonde data

TL;DR

This study analyzes global radiosonde data from 2014 to 2025 to map stratospheric turbulence, revealing its distribution, contributing factors, and implications for aerosol dispersion and geoengineering.

Contribution

It provides the first comprehensive global map of stratospheric turbulent diffusivity using high-resolution radiosonde data and a Richardson-number-based estimation method.

Findings

Turbulent diffusivity varies widely and is linked to stable, sheared conditions.

Enhanced turbulence occurs over mountainous regions and near the tropical tropopause.

Stratospheric turbulence increased significantly from 2015 to 2025.

Abstract

Stratospheric turbulence is difficult to observe, yet it strongly affects how momentum, trace gases, and aerosols spread through the atmosphere. Here, we use global high-resolution radiosonde observations from 370 stations during October 2014-December 2025 to estimate stratospheric turbulent diffusivity with a Richardson-number-based method. We find that turbulent diffusivity spans a broad range and is dominated by turbulence occurring in statically stable but strongly sheared conditions. Enhanced values appear over Turkey, India, Malaysia, Japan, and major mountainous regions, with evidence that mountain waves and convective activity both contribute. We also identify a local maximum just above the tropical tropopause, between the Equator and 15 N at 17 km altitude, which may indicate an injection region conducive to the rapid aerosol dispersion for stratospheric aerosol injection (SAI). Stratospheric turbulent diffusivity also shows a significant increase ($3.5 \times 10^{-3}\ \mathrm{m^2\ s^{-1}\ yr^{-1}}$) over 2015-2025. Finally, these results may help constrain and predict the dispersion of stratospheric plumes from rockets, aircraft, and potential SAI.