Dynamic Relationship Between Entrainment Rate and Summer Monsoon in the Transition Area of Monsoon in the East of Northwest China

  • Yanying Li ,
  • Ying Cai ,
  • Chunyan Zhang ,
  • Ting Zeng ,
  • Jiping Yang
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  • 1.Key Laboratory of Arid Climatic Change and Reducing Disaster of Gansu Province/Key Open Laboratory of Arid Climatic Change and Disaster Reduction of CMA/ Institute of Arid Meteorology,CMA,Lanzhou 730020, China
    2.Key Laboratory of Land Surface Process and Climate Change in Cold and Arid Regions, CAS, Lanzhou 730000, China
    3.Wuwei Meteorological Bureau in Gansu Province, Gansu Wuwei 733000, China
    4.Minqin Meteorological Bureau of Gansu Province, Gansu Minqin 733300, China
Li Yanying (1970-), female, Wuwei City, Gansu Province, Professor of engineering. Research areas include weather forecasting and research. E-mail: lyyqxj@163.com

Received date: 2019-09-11

  Revised date: 2019-11-02

  Online published: 2020-02-12

Supported by

the National Natural Science Foundation of China "Study on land-air interaction and its response to summer monsoon in transition area affected by typical summer monsoon in China"(41630426);The Open Fund of the Key Laboratory of Land Surface Process and Climate Change of the Chinese Academy of Sciences "Characteristics of atmospheric boundary layer variation in the East of Northwest China and its response to summer monsoon activities"(LPCC2016005)

Abstract

Entrainment rate refers to the ratio of surrounding air quality to air quality involved in rising unit distance, including turbulent entrainment and dynamic entrainment, which are applied to the boundary layer parametrization of convective clouds, the improvement of numerical model, the observation of cloud droplet spectral dispersion and the study of tropical cyclones.Based on the daily data at 07:00 and 19:00 every 10 m of five stations such as Minqin, Yuchong, Pingliang, Yinchuan and Yan'an from May to September during 2006-2016, combined with the daily observation data on the ground, the Entrainment Rates(ER) of different heights were calculated, and the relationships between ER and height in different regions, precipitation as well as monsoon during the monsoon period were further obtained. The main results were as follows: The ER was proportional to air temperature and saturated water vapor pressure, but inversely proportional to relative humidity. The relative humidity threshold of cloud was 65%. The higher the relative humidity threshold was, the lower the cloud height of different orders of precipitation was, and the cloud height was higher with the increase of rainfall. ER had obvious diurnal changes and regional differences: It was obviously smaller at 07:00 than at 19:00 from ground to 3 km, which weakened with the increase of height in the near surface , but strengthened with the increase of height above 500 m; From small to large, the monsoon affected area, the monsoon swing area and the non-monsoon area were in turn, and there was no regional difference above 3 km. ER was closely related to the intensity and property of precipitation in monsoon period. The ER weakened with the enhancement of rain intensity from near ground to below 600 m, but strengthened with the enhancement of rain intensity from 500 m to 2~3 km.From near ground to below 700 m, the ER of stable precipitation was strong, but that of convective precipitation was strong above 700 m. The convective precipitation had big saturated water vapor pressure and strong ER , while the stable precipitation had big saturated water vapor density, rich water vapor but weak ER. The relationship between ER and monsoon as well as its duration: From no monsoon to monsoon ER was weakened, the strongest maximum height was also decreasing. There was no significant difference in the duration of ER between the non-monsoon area and the monsoon affected area, but the longer the monsoon swing area lasted in the near ground layer, the smaller the ER was, while the opposite was at 1~2 km in the high altitude. The relationship between ER and the APO monsoon intensity index showed that: At 07:00, the ER strengthened with height from near ground to below 800 m, but weakened with height above 800 m,and the monsoon intensity was not related to the ER. At 19:00, the ER strengthened with the height near ground but weakened with the height above 300 m, and the stronger the monsoon was, the smaller the ER was. The ER weakened with the decrease of boundary layer height.

Cite this article

Yanying Li , Ying Cai , Chunyan Zhang , Ting Zeng , Jiping Yang . Dynamic Relationship Between Entrainment Rate and Summer Monsoon in the Transition Area of Monsoon in the East of Northwest China[J]. Advances in Earth Science, 2019 , 34(12) : 1316 -1327 . DOI: 10.11867/j.issn.1001-8166.2019.12.1316

References

1 Song G, Zhang D, Liu Q, et al. RELAP5/MOD3. 4 calculation and model evaluation based on upper plenum entrainment experiment in AP1000[J]. Annals of Nuclear Energy, 2020, 138: 107143.
2 Stanfield R E, Su H, Jiang J H, et al. Convective entrainment rates estimated from aura CO and CloudSat/CALIPSO observations and comparison with GEOS‐5[J]. Journal of Geophysical Research:Atmospheres,2019,124(17/18). DOI:10.1029/2019JD030846.
3 Han K H, Yoo J M, Yun B J, et al. Development of a droplet entrainment rate model for a vertical adiabatic two-phase flow[J]. Annals of Nuclear Energy, 2019, 132: 181-190.
4 Drueke S, Kirshbaum D J, Kollias P. Evaluation of shallow‐cumulus entrainment rate retrievals using large‐eddy simulation[J]. Journal of Geophysical Research: Atmospheres,2019,124(16). DOI:10.1029/2019JD030889.
5 Lu C S, Liu Y G, Niu S J. Entrainment-mixing parameterization in shallow cumuli and effects of secondary mixing events[J]. Chinese Science Bulletin, 2014, 59(9): 896-903.
6 Lu Chunsong, Guo Xiaohao, Liu Yan'gang, et al. The observation and simulation of the effect of the convective clamp on the dispersion degree of the cloud drop spectrum[C]//The 34th China Meteorological Society of China in the Proceedings of the Physical and Atmospheric Environment of S10,2017.
6 陆春松,郭小浩,刘延刚,等.对流夹卷对云滴谱离散度影响的观测和模拟研究[C]//第34届中国气象学会年会S10大气物理学与大气环境论文集,2017.
7 Lu Chunsong, Liu Yan'gang, SooYum Seong, et al. A new method for calculating entrainment rate in cumulus clouds [C]//Innovation-driven Development to Improve Meteorological Disaster Defense Ability—S14 Artificial Influence Weather and the Development and Utilization of Atmospheric Water Resources, 2013.
7 陆春松,刘延刚,SooYum Seong,等.一个估算积云中夹卷率的新方法[C]//创新驱动发展 提高气象灾害防御能力——S14人工影响天气与大气水资源开发利用,2013.
8 Guo Xiaohao. Observation and study on entrainment rate of deep convective clouds [C]//Commission on Artificial Influence Weather, China Academy of Meteorological Sciences. 31st Annual Meeting of China Meteorological Society S8 16th National Conference on Cloud Precipitation and Artificial Influence Weather Science Conference on the Development and Utilization of Atmospheric Water Resources and Meteorological Disaster Prevention and Mitigation, 2014.
8 郭小浩. 深对流云夹卷率观测研究[C]//人工影响天气委员会,中国气象科学研究院.第31届中国气象学会年会S8第16届全国云降水与人工影响天气科学会议——大气水资源开发利用与气象防灾减灾,2014.
9 Guo Xiaohao. Study on Cumulus Cloud Entrainment and Its Parametrization and Cloud System Interaction Based on Aircraft Observation and Numerical Simulation [D]. Nanjing:Nanjing University of Information Engineering, 2017.
9 郭小浩.基于飞机观测和数值模拟的积云夹卷及其参数化和云系相互作用研究[D].南京:南京信息工程大学,2017.
10 Khairoutdinov M, Randall D. High-resolution simulation of shallow-to-deep convection transition over land[J]. Journal of the Atmospheric Sciences, 2006, 63(12): 3 421-3 436.
11 De Rooy W C, Bechtold P, Fr?hlich K, et al. Entrainment and detrainment in cumulus convection: An overview[J]. Quarterly Journal of the Royal Meteorological Society,2013,139(670): 1-19.
12 Jensen M P, Del Genio A D. Factors limiting convective cloud-top height at the ARM Nauru Island climate research facility[J]. Journal of Climate, 2006, 19(10): 2 105-2 117.
13 Cheng M, Lu C, Liu Y. Variation in entrainment rate and relationship with cloud microphysical properties on the scale of 5 m[J]. Science Bulletin, 2015, 60(7): 707-717.
14 Wan Rong, Li Jin, Wang Zhibin. Mesoscale and cloud-mode nesting test[J]. Meteorological Monthly,2006,32 (5):16-21.
14 万蓉,李劲,王志斌.中尺度和云模式嵌套试验[J].气象,2006,32(5):16-21.
15 Luo Shi, Lu Chunsong, Guo Xiaohao, et al. Numerical simulation study on the effect of entrainment mixing process on cloud drop spectrum and microphysical quantity in Qinghai-Xizang Plateau[J]. Chinese Science and Technology Paper, 2017, 12 (9): 972-977.
15 罗仕,陆春松,郭小浩,等,夹卷混合过程对青藏高原云滴谱及微物理量影响的数值模拟研究[J].中国科技论文,2017,12(9):972-977.
16 Sun Li, Zhao Shuhui. Research on humidity measurement error of radiosonde and its influence on cloud recognition[J]. Advances in Earth Science, 2018, 33(1): 85-92.
16 孙丽, 赵姝慧. 探空仪湿度测量误差研究现状及其对云识别的影响[J]. 地球科学进展, 2018, 33(1): 85-92.
17 Liu Jianchao. Using Satellite and Other Remote Sensing Methods to Study Cloud Characteristics [D]. Nanjing: Nanjing University of Information Engineering, 2011.
17 刘建朝.利用卫星等遥感方法对云特征的研究[D].南京:南京信息工程大学,2011.
18 Zhang Q Y, Tao S Y, Chen L T. The interannual variability of East Asian summer monsoon indices and its association with the pattern of general circulation over East Asia[J]. Acta Meteorologica Sinica, 2003, 61(4): 559-568.
19 Li J, Zeng Q. A unified monsoon index[J]. Geophysical Research Letters, 2002, 29(8): 115-1-115-4.
20 Zhao P, Zhu Y, Zhang R. An Asian-Pacific teleconnection in summer tropospheric temperature and associated Asian climate variability[J]. Climate Dynamics, 2007, 29(2/3): 293-303.
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