How high can desert dust rise? Dust storms are most visible near the ground, where they darken the sky and reduce visibility. But some dust is lifted high into the atmosphere and carried far from its source by strong winds. This matters because dust in the upper troposphere can act as ice nuclei, influence cirrus cloud formation, and thereby affect Earth’s energy balance. Dust that reaches the upper troposphere may also travel long distances on westerly jets before being removed.
Ground-based and satellite lidar observations have detected dust at high altitudes. Aircraft and balloon-borne instruments have also sampled dust directly in the upper troposphere, while simulations have traced possible transport pathways. Yet in situ evidence of how dust rises through the troposphere and crosses the tropopause remains limited. The tropopause separates the troposphere, where most weather occurs, from the stratosphere above. This gap has left a key stage of the dust journey poorly documented.
A new study published in Advances in Atmospheric Sciences helps fill this gap. The authors report balloon-borne, in situ measurements of dust transport to the tropopause layer over the northern Qinghai-Tibet Plateau (TP), offering a fresh observational perspective on a process that has mostly been inferred from remote sensing and models.
The TP offers a practical advantage for this kind of experiment. Golmud sits at about 2,800 meters above sea level in the Qaidam Basin, on the plateau’s northern flank. While not among the highest points on the plateau, this launch site still starts several kilometers above sea level—meaning a balloon released there begins much closer to the tropopause than one launched from lowland sites. That gives scientists a shorter ascent and a better chance to capture how dust behaves near the boundary between the troposphere and the stratosphere.
The observations were part of the Sounding Water Vapour, Ozone, and Particle campaign, or SWOP, organized by the Institute of Atmospheric Physics, Chinese Academy of Sciences. Corresponding author Jianchun Bian led the campaign. He and his team members, including atmospheric scientist Dan Li, senior engineer Zhixuan Bai, and other specialists, are also co-authors of the study. Since 2009, they have used instrumented balloons to measure atmospheric composition over the TP.
This was not the team’s first encounter with high-altitude dust. In March 2021, a SWOP balloon sounding over Golmud documented dust in the upper troposphere and lower stratosphere, tracing dust near the tropopause back to a dust storm over the Middle East and northeastern Africa . The 2023 campaign offered a chance to observe such a transport event again, this time with a dust event directly affecting Golmud.
During that campaign, the team conducted two balloon soundings. The first, before the dust arrived, provided a reference profile. During the event, a second instrumented balloon rose from Golmud carrying a compact particle counter.
When the team compared the two profiles, the difference was clear. Larger particles associated with dust were more abundant throughout the troposphere, and the increase extended above the tropopause.
“A balloon sounding provides a vertical snapshot of the atmosphere, giving us a direct, layer-by-layer view of its particles,” said Bian. “Combined with satellite observations and atmospheric simulations, this snapshot can help reveal how dust travels from distant deserts into the lower stratosphere.”
The next question was where the particles came from. Combining the balloon records with satellite observations and atmospheric simulations, the team traced the air masses back to their source regions. Dust at lower altitudes came mainly from the nearby Taklamakan Desert. Dust above the tropopause was traced to the distant Thar Desert, about a 30-hour journey to Golmud. The evidence suggests that a trough and jet streams helped lift dust over the Thar Desert, southwesterly winds carried it toward Golmud, and the high terrain of the Tibetan Plateau lifted it even higher.
The measurements provide valuable observational data for evaluating dust-transport models and highlight the value of sustained balloon observations over the TP.
Advances in Atmospheric Sciences
In Situ Measurement of Dust Particle Transport to the Tropopause Layer over the Northern Tibetan Plateau
28-Sep-2026