干旱区研究 ›› 2022, Vol. 39 ›› Issue (4): 1006-1016.doi: 10.13866/j.azr.2022.04.02

• 天气与应用气候 • 上一篇    下一篇

不同起沙阈值判定方案在塔克拉玛干沙漠的适用性对比研究

杨兴华1,2(),马明杰2,周成龙2,何清2()   

  1. 1.山西师范大学地理科学学院,山西 太原 030032
    2.新疆塔克拉玛干沙漠气象国家野外科学观测研究站,新疆 乌鲁木齐 830002
  • 收稿日期:2021-12-01 修回日期:2021-12-27 出版日期:2022-07-15 发布日期:2022-09-26
  • 通讯作者: 何清
  • 作者简介:杨兴华(1982-),男,博士,研究员,主要从事沙漠气象研究. E-mail: yxhidm@126.com
  • 基金资助:
    国家自然科学基金(41905009);国家自然科学基金(41875019)

Comparative study of the applicability of emission threshold determining method in the Taklimakan Desert

YANG Xinghua1,2(),MA Mingjie2,ZHOU Chenglong2,HE Qing2()   

  1. 1. School of Geographical Sciences, Shanxi Normal University, Taiyuan 030032, Shanxi, China
    2. National Observation and Research Station of Desert Meteorology, Taklimakan Desert in Xinjiang, Urumqi 830002, Xinjiang, China
  • Received:2021-12-01 Revised:2021-12-27 Online:2022-07-15 Published:2022-09-26
  • Contact: Qing HE

摘要:

风沙运动是区域与全球变化研究中不可忽视的地表过程。起沙阈值(临界起沙风速、临界起沙摩擦速度)作为判定风沙运动是否发生的关键参数,是风沙运动研究的核心问题。利用塔克拉玛干沙漠腹地野外同步观测的风沙运动和气象资料,结合数理模型计算,定量评估了Stout、Kurosaki and Mikami(KM)、李晓岚和张宏升(LZ)、Marticorena and Bergametti(MB)、Shao and Lu(SL)5种起沙阈值判定方案的适用性,并利用最优方案确定了研究区新的起沙阈值。结果表明:(1) 5种方案均存在不确定性,KM方案确定的起沙阈值一定程度上高估了起沙时长与沙尘水平通量,其他4种方案则相反,但KM方案最优。(2) 塔克拉玛干沙漠腹地2 m高度临界起沙风速变化范围为4.0~6.0 m·s-1,临界起沙摩擦速度变化范围为0.24~0.36 m·s-1;起沙阈值具有季节性差异,符合夏季>秋季>春季>冬季的变化规律。

关键词: 风沙运动, 临界起沙风速, 临界起沙摩擦速度, 塔克拉玛干沙漠

Abstract:

Aeolian sand movement is a crucial surface process in the study of regional and global changes. As a key parameter in determining wind-sand movement occurrence, the emission threshold (threshold velocity, threshold friction velocity) is a core issue in the study of wind-sand movement. Taking the Taklimakan Desert as the target area, using synchronously observed wind-sand movement and meteorological data in the field, combined with mathematical model calculations, the applicability of five emission threshold judgment schemes from Stout, Kurosaki and Mikami (KM), Li Xiaolan and Zhang Hongsheng (LZ), Marticorena and Bergametti (MB), and Shao and Lu (SL) was quantitatively assessed, and the optimal scheme was used to determine the new emission threshold of the Taklimakan Desert. The following results are presented. (1) Uncertainties exist in all five schemes. The emission threshold determined by the KM scheme overestimates the dust emission time and the dust level flux to a certain extent. The four other schemes are opposite, but the KM scheme is the best. (2) The 2 m threshold velocity in the hinterland of the Taklimakan Desert varies from 4.0 m·s-1 to 6.0 m·s-1, and the threshold friction velocity varies from 0.24 m·s-1 to 0.36 m·s-1. Moreover, the emission threshold has seasonal differences, which is consistent with summer > autumn > spring > winter.

Key words: wind-blown sand movement, threshold velocity, threshold friction velocity, Taklimakan Desert