This research was led by Prof. Chang Lai and collaborators from the National Space Science Center. The team analyzed 979,743 airglow images from the Chinese Meridian Project, identifying 519 AGW events—317 at Dandong and 202 at Lhasa—using a machine learning-based detection model.
The study revealed contrasts in AGW characteristics between the two sites. At Dandong, waves exhibited longer horizontal wavelengths (35–50 km), periods of 14–20 minutes, and higher relative intensities (0.4–0.6%). In contrast, AGWs at Lhasa had shorter wavelengths (10–30 km), faster propagation speeds (40–100 m/s), and lower intensities (0.1–0.3%).
Seasonal occurrence rates also differed significantly. Dandong experienced peaks in both summer and winter, while Lhasa showed only a winter peak. "The absence of a summer peak at Lhasa is likely due to fewer convective weather events," Chang Lai says.
Propagation directions were strongly influenced by wind-field filtering effects. In summer, northeastward waves dominated at both sites. In winter, Dandong saw predominantly southwestward propagation, whereas Lhasa’s waves shifted southeastward—a trend potentially linked to secondary wave generation.
Backward ray-tracing analysis traced 63% of Dandong’s events to tropospheric sources (below 13 km), compared to only 20% at Lhasa. Convection and wind shear were identified as primary triggers.
See the article:
Comparative Study Reveals Seasonal Characters of Atmospheric Gravity Waves in Dandong and Lhasa
http://doi.org/10.26464/epp2026002
Earth and Planetary Physics
Comparison of atmospheric gravity wave event statistics between Dandong and Lhasa
10-Jan-2026