Multi-year ground-based multi-wavelength Raman lidar aerosol dataset over the interior Tibetan Plateau (Yangbajing, 4284 m a.s.l.; 2021–2024)

Abstract. The interior of the Tibetan Plateau exerts a first-order influence on the Asian monsoon and regional climate, yet vertically resolved aerosol observations there are scarce, and no openly archived, multi-year, ground-based profile record has existed for this exceptionally clean high-altitude environment. We present such a dataset from a six-channel elastic/Raman/depolarisation lidar (355, 387, 408, 532, 607, 1064 nm) at Yangbajing (30.10° N, 90.52° E, 4284 m a.s.l.), covering September 2021 to December 2024: 437 quality-controlled nighttime profiles on a 75 m grid (157 levels, 0.30 to 12 km a.g.l.) and 279 daytime column-AOD retrievals. The independent products are the nitrogen-Raman extinction at 355 and 532 nm and the Raman-derived lidar ratio. The aerosol backscatter at 355 and 532 nm is retrieved by the elastic (Fernald) inversion with an assumed lidar ratio of 50 sr, and the 1064 nm backscatter is a non-independent colour-ratio transfer. Volume and particle depolarisation ratios (532 nm), water vapour mixing ratio (408/387 nm; radiosonde-calibrated C = 90.4 g kg-1, ~17 % uncertainty), Ångström exponents and column aerosol optical depth (AOD) complete the product set, and a scattering-ratio cloud screen supplemented by a particle-depolarisation ice test separates mineral dust from ice. The site is among the cleanest continental settings sampled by lidar: the nighttime detection-night median column AOD at 532 nm is 0.053 (n = 269) and the daytime detection median is 0.078 (n = 208). The Raman-derived site-mean lidar ratio is 51.6 sr (IQR 41 to 80 sr, n = 85), consistent in the median with the assumed 50 sr and with the CALIPSO clean-continental value, but it varies by a factor of two from night to night. This assumption, not photon noise (median relative σ ~1.7 % for the 532 nm extinction, rising to a 90th percentile of ~24 % in the weak-signal upper troposphere), dominates the column-AOD uncertainty (+60 %/-18 %), for which per-profile S = 41 and 80 sr bounds are provided. Daytime AOD tracks AERONET Nam Co (~85 km) in rank order (Pearson r = 0.61, Spearman ρ = 0.72, both p < 0.001, n = 41). To our knowledge this is the first openly archived, multi-year, ground-based multi-wavelength aerosol profile dataset from the clean interior Tibetan Plateau, a region pivotal for the Asian monsoon and the Third Pole cryosphere where high surface albedo and complex terrain defeat passive retrievals and leave spaceborne lidar the de facto reference. It supplies the vertically resolved ground truth needed to evaluate and correct spaceborne-lidar aerosol detection and typing, to benchmark next-generation missions such as EarthCARE over bright, high terrain, and to constrain reanalysis, model, and aerosol radiative studies of dust transport and monsoon aerosol over the Third Pole.