Comparative Analyses of Vertical Structure of Deep Convective Clouds Retrieved from Satellites and Ground-Based Radars at Naqu over the Tibetan Plateau
- 131 Downloads
In order to improve understanding of deep convective clouds over the Tibetan Plateau, characteristics of vertical structure of a deep strong convective cloud over Naqu station and a deep weak convective cloud approximately 100 km to the west of Naqu station, which occurred over 1300–1600 Beijing Time (BT) 9 July 2014 during the Third Tibetan Plateau Atmospheric Science Experiment (TIPEX-III), are analyzed, based on multi-source satellite data from TRMM, CloudSat, and Aqua, and radar data from ground-based vertically pointing radars (C-band frequency-modulated continuous-wave radar and KA-band millimeter wave cloud radar). The results are as follows. (1) The horizontal scales of both the deep strong and deep weak convective clouds were small (10–20 km), and their tops were high [15–16 km above sea level (ASL)]. Across the level of 0°C isotherm in the deep strong convective cloud, the reflectivity increased rapidly, suggesting that the melting process of solid precipitation particles through the 0°C level played an important role. A bright band located at 5.5 km ASL (i.e., 1 km above ground level) appeared during the period of convection weakening. (2) The reflectivity values from TRMM precipitation radar below 11 km were found to be overestimated compared to those derived from the C-band frequency-modulated continuous-wave radar. (3) Deep convective clouds were mainly ice clouds, and there were rich small ice particles above 10 km, while few large ice particles were found below 10 km. The microphysical processes of deep strong and deep weak convective clouds mainly included mixed-phase process and glaciated process, and the mixed-phase process can be divided into two types: one was the rimming process below the level of −25°C (deep strong convective cloud) or −29°C (deep weak convective cloud) and the other was aggregation and deposition process above that level. The latter process was accompanied with fast increase in ice particle effective radius. The above evidence from space-based and ground-based observational data further clarify the characteristics of vertical structure of deep convective clouds over the Tibetan Plateau, and provide a basis for the evaluation of simulation results of deep convective clouds by cloud models.
Key wordsdeep convective clouds the Tibetan Plateau vertical structure satellite retrieval radar observation
Unable to display preview. Download preview PDF.
We acknowledge the team of the Third Tibetan Plateau Atmospheric Science Experiment for providing the surface observations of cloud and precipitation. Many thanks go to Professor Zhijin Hu, Professor Xiaofeng Lou, and Dr. Jing Duan for offering great suggestions and comments for the present study.
- Dai, J., X. Yu, G. H. Liu, et al., 2011: Satellite retrieval analysis on microphysical property of thunderstorm with light precipitation over the Qinghai-Tibet Plateau. Plateau Meteor., 30, 288–298. (in Chinese)Google Scholar
- Feng, J. M., L. P. Liu, Z. J. Wang, et al., 2001: Comparison of cloud observed by ground based Doppler radar with TRMM PR in Qinghai-Tibet Plateau, China. Plateau Meteor., 20, 345–353. (in Chinese)Google Scholar
- Flohn, H., 1968: Contributions to a meteorology of the Tibetan highlands. Atmospheric science paper, No. 130, Colorado State University, Fort Collins, 120 pp.Google Scholar
- Fu, Y. F., H. T. Li, and Y. Zi, 2007: Case study of precipitation cloud structure viewed by TRMM satellite in a valley of the Tibetan Plateau. Plateau Meteor, 26, 98–106. (in Chinese)Google Scholar
- Fu, Y. F., X. Pan, G. S. Liu, et al., 2016: Characteristics of precipitation based on cloud brightness temperatures and storm tops in summer Tibetan Plateau. Chinese J. Atmos. Sci, 40, 102–120, DOI: https://doi.org/10.3878/j.issn.1006-9895.1507.15165. (in Chinese)Google Scholar
- Jiang, J. X., X. K. Xiang, M. Z. Fan, 1996: The spatial and temporal distributions of severe mesoscale convective systems over Tibetan Plateau in summer. J. Appl. Meteor. Sci., 7, 473–478. (in Chinese)Google Scholar
- Li, D., A. J. Bai, and S. J. Huang, 2012: Characteristic analysis of a severe convective weather over Tibetan Plateau based on TRMM data. Plateau Meteor., 31, 304–311. (in Chinese)Google Scholar
- Liu, J. J., and B. D. Chen, 2017: Cloud occurrence frequency and structure over the Qinghai-Tibetan plateau from CloudSat observation. Plateau Meteor., 36, 632–642, DOI: https://doi.org/10.7522/j.issn.1000-0534.2017.00028. (in Chinese)Google Scholar
- Luo, Y. L., R. H. Zhang, W. M. Qian, et al., 2011: Intercomparison of deep convection over the Tibetan Plateau-Asian monsoon region and subtropical North America in boreal summer using CloudSat/CALIPOS data. J. Climate, 24, 2164–2177, DOI: https://doi.org/10.1175/2010JCLI4032.1.CrossRefGoogle Scholar
- Oye, D., and M. Case, 1995: REORDER: A Program for Gridding Radar Data—Installation and Use Manual for the UNIX Version. NCAR/ATD. Boulder, CO, USA, 30 pp.Google Scholar
- Pan, X., and Y. F. Fu, 2015: Analysis on climatological characteristics of deep and shallow precipitation cloud in summer over Qinghai-Tibet Plateau. Plateau Meteor., 34, 1191–1203, DOI: https://doi.org/10.7522/j.issn.l000-0534.2014.00112. (in Chinese)Google Scholar
- Platnick, S., M. D. King, K. G. Meyer, et al., 2015: MODIS Cloud Optical Properties: User Guide for the Collection 6 Level-2 MOD06/MYD06 Product and Associated Level-3 Datasets. Version 1.0, NASA Goddard Space Flight Center, Greenbelt, MD, USA, 141 pp.Google Scholar
- Rosenfeld, D., and W. L. Woodley, 2000: Deep convective clouds with sustained supercooled liquid water down to −37.5°C. Nature, 440–442, DOI: https://doi.org/10.1038/35013030.
- Wang, H., Y. L. Luo, R. H. Zhang, 2011: Analyzing seasonal variation of clouds over the Asian monsoon regions and the Tibetan Plateau region using CloudSat/CALIPSO data. Chinese J. Atmos. Sci., 35, 1117–1131. (in Chinese)Google Scholar
- Wang, S. H., Z. G. Han, Z. G. Yao, et al., 2011: An analysis of cloud types and macroscopic characteristics over China and its neighborhood based on the CloudSat data. Acta Meteor. Sinica, 69, 883–899. (in Chinese)Google Scholar
- Zhao, Y. F., D. H. Wang, and J. F. Yin, 2014: A study on cloud microphysical characteristics over the Tibetan Plateau using CloudSat data. J. Trop. Meteor., 30, 239–248, DOI: https://doi.org/10.3969/j.issn.1004-4965.2014.02.005. (in Chinese)Google Scholar