干旱区研究 ›› 2025, Vol. 42 ›› Issue (11): 2117-2126.doi: 10.13866/j.azr.2025.11.14

• 生态与环境 • 上一篇    下一篇

青藏高原大气气溶胶垂直分布的飞机观测

张玉欣1(), 张博越2(), 侯永慧2, 康晓燕1   

  1. 1.青海省气象灾害防御技术中心,青海 西宁 810000
    2.青海省人工影响天气中心,青海 西宁 810000
  • 收稿日期:2025-04-07 修回日期:2025-05-31 出版日期:2025-11-15 发布日期:2025-12-13
  • 通讯作者: 张博越. E-mail: rybzhk@163.com
  • 作者简介:张玉欣(1993-),女,工程师,主要从事大气物理研究. E-mail: nuistzyx@126.com
  • 基金资助:
    国家自然科学基金(42165008);青海省自然科学基金(2023-ZJ-727);青海省气象局重点科研项目(QXZD2023-07)

Airborne observation of the vertical distribution of atmospheric aerosols over the Qinghai-Xizang Plateau

ZHANG Yuxin1(), ZHANG Boyue2(), HOU Yonghui2, KANG Xiaoyan1   

  1. 1. Meteorological Disaster Prevention Technology Center in Qinghai Province, Xining 810000, Qinghai, China
    2. Qinghai Weather Modification Center, Xining 810000, Qinghai, China
  • Received:2025-04-07 Revised:2025-05-31 Published:2025-11-15 Online:2025-12-13

摘要: 利用2020年5月18—22日5次飞机机载观测数据,对青藏高原东北部大气气溶胶的颗粒物粒径分布和浓度垂直差异进行分析,构建背景气溶胶谱特征。结果表明:(1) 研究区域中分散云系自西向东移动,云顶高度(Cloud Top Height,CTH)在8000~10000 m之间。后向轨迹表明6000~7000 m主要受周边环境传输影响,高空气溶胶粒子与远距离大气传输相关,来自青藏高原边缘。(2) 大气气溶胶平均有效直径(re)为0.68 μm,平均浓度(Na)为102~103 cm-3。气溶胶谱型为多峰型。(3) 气溶胶分为3种模态,Mode I的Na为102 cm-3,Mode II的Na为101 cm-3,Mode III的Na为10-1~100 cm-3Na随高度升高而降低,随着温度(T)的下降而下降,NaT呈显著正相关。随相对湿度(RH)的升高,气溶胶谱型不变,但气溶胶粒子数(dNa)和粒子直径(D)的比值(dNa/dD)逐渐上升。(4) 云滴离散度(ε)表征云滴大小的不均匀性,7000~8000 m时ε值较高在0.4左右,该高度处云滴尺度变化最显著。文中对ε-Na进行了线性拟合和幂指数拟合,两种拟合均表明ε-Na为负相关关系。

关键词: 飞机观测, 气溶胶, 垂直分布, 离散度, 青藏高原

Abstract:

To analyze the vertical variations of particle size distribution and atmospheric particulate concentrations in the middle and lower atmosphere of the Qinghai-Xizang Plateau and clarify the characteristics of the background aerosol spectra, this study utilized the aircraft-borne observational data from five flights in 2020 to analyze the size distribution and number concentration of atmospheric aerosols in the northeastern part of the Qinghai-Xizang Plateau. (1) The scattered cloud systems in the research area moved from west to east, with the cloud top height ranging from 8000 to 10000 m. The backward trajectories demonstrated that the altitude range of 6000-7000 m was primarily affected by the surrounding environmental transmission. The high-altitude aerosol particles were associated with long-distance atmospheric transport, and they originated from the edge of the Qinghai-Xizang Plateau. (2) Aerosols in the middle and lower atmospheric layers over the northeastern Qinghai-Xizang Plateau were predominantly small particles with an average effective diameter (re) of 0.68 μm and an average concentration (Na) of 102-103 cm-3. On average, Na and re reached 507.16 cm-3 and 0.40 μm, respectively, in the vertical profile, exhibiting a multi-peak structure. (3) The aerosols could be categorized into three modes, with Mode I having mean Na of 102 cm-3 and Mode II having mean Na of 101 cm-3. For Mode III, mean Na ranged 10-1-100 cm-3. Na decreased with increasing altitude. Na gradually decreased with decreasing temperature, indicating a significant positive correlation. As relative humidity increased, the aerosol spectral type remained stable, but the concentration gradually increased. (4) At vertical heights of 7000-8000 m, the relative dispersion of cloud droplet (ε) value was relatively high at approximately 0.4, suggesting that cloud droplet sizes vary more significantly at this altitude range. Linear fitting and power-law both indicated a negative correlation between ε and Na.

Key words: airborne observation, aerosols, vertical distribution, relative dispersion, Qinghai-Xizang Plateau