Vol.24, NO.2, 2013
Turn off MathJax
Article Contents
Article Navigation >  Journal of Applied Meteorological Science  > 2013  >  24(2): 179-188
Hu Shuzhen, Ma Shuqing, Tao Fa, et al. An experiment study of all-sky cloud amount observation based on infrared real-time threshold. J Appl Meteor Sci, 2013, 24(2): 179-188.
Citation: Hu Shuzhen, Ma Shuqing, Tao Fa, et al. An experiment study of all-sky cloud amount observation based on infrared real-time threshold. J Appl Meteor Sci, 2013, 24(2): 179-188.
shu

An Experiment Study of All-sky Cloud Amount Observation Based on Infrared Real-time Threshold

  • 1.

    CMA Meteorological Observation Center, Beijing 100081

  • 2.

    Beijing Meteorological Service, Beijing 100089

  • Received Date: 2012-06-28
  • Rev Recd Date: 2012-12-26
  • Publish Date: 2013-04-30
    Abstract
  • The cloud typically covers about 50% of the earth surface, affecting the energy balance, water circulation of the earth, and influencing global climate. Cloud cover and cloud base height are the primary elements in the observation of clouds, wherein the cloud amount reflects the regional weather and climate characteristics. However, the operating artificial observation method for cloud amount in China lacks objectivity and costs too much workforce. Therefore, the research and development of an automatic measuring cloud device is extremely necessary.An infrared cloud detector based on the different characteristics of visible and infrared cloud images is developed in order to measure cloud amount. The infrared sensors regularly scan the whole sky under the control of the rotating platform, and stitching all-sky images of infrared brightness temperature. Based on the different characteristics of cloud images shown in infrared, different temperature at different elevation for the cloud point and non-cloud point is considered, combining with real-time infrared brightness temperature and ground environmental parameters. The temperature threshold functions are real-time determined from the zenith to the horizontal, the all-sky cloud distribution and cloud amount are derived using the method of segmentation. This method is effective in reducing the ground environmental parameters and the sunlight on the cloud images, and it can run properly throughout the day. The cloud measuring system can provide real-time analysis of the sky condition, cloud distribution and cloud amount. The system is fully automated and adaptable for all weather conditions, with high temporal resolution and accurate observation time, and it can show the cloud trajectory of the whole period and cloudiness trends.Measurements of cloud system has been performed experimental observation in the synthesize experiment base of Meteorological Observation Center of CMA since May 2011. Through the comparative data analysis with the results of artificial observations and the visible cloud images, this measurement of cloud systems are proved to be able to provide results with high accuracy.
    • FullText(HTML)
    References(17)

  • Fig. 1  A photo for the SIRIS-1

    DownLoad: Full-Size Img PowerPoint

    Fig. 2  The schematic diagram of spherical projection

    DownLoad: Full-Size Img PowerPoint

    Fig. 3  The cloud images of visible light and the whole sky maps of brightness temperature

    (a) the visible map at 1132 BT 7 July 2011, (b) the brightness map at 1130 BT 7 July 2011, (c) the visible map at 1802 BT 7 July 2011, (d) the brightness map at 1800 BT 7 July 2011

    DownLoad: Full-Size Img PowerPoint

    Fig. 4  Relations between scan time and infrared brightness temperature

    (a) brightness temperature trends at clear sky moment, (b) cloudy brightness temperature trends at cloudy moment

    DownLoad: Full-Size Img PowerPoint

    Fig. 5  Whole sky full of clouds, radiation image of brightness temperature and brightness temperature trends

    (a) the brightness map at 0300 BT 7 July 2011, (b) cloudy and sunny brightness temperature trends

    DownLoad: Full-Size Img PowerPoint

    Fig. 6  Low-visibility, relations between scan time and infrared brightness temperature

    (a) the brightness map at 1010 BT 23 August 2011, (b) the brightness map at 1110 BT 23 August 2011, (c) the brightness temperature trends of Fig. 6a and Fig. 6b

    DownLoad: Full-Size Img PowerPoint

    Fig. 7  Relations between infrared brightness temperature and pitch angle

    (a) the brightness temperature trend of different time under the clear sky radiations, (b) the trend of sky brightness temperature minus the ground temperature

    DownLoad: Full-Size Img PowerPoint

    Fig. 8  Comparisons of artificial observed cloud amount and infrared observed cloud amount

    (a) middle and low cloud situations with high visibility, (b) middle and low cloud situations with low visibility, (c) cirrus with high visibility

    DownLoad: Full-Size Img PowerPoint

    Fig. 9  The cloud amount distribution of manual observation and ground-based measurements of cloud systems

    DownLoad: Full-Size Img PowerPoint

    Fig. 10  The percentage relative error of manual observation and ground-based measurements of cloud systems

    DownLoad: Full-Size Img PowerPoint
  • [1]
    徐兴奎.中国区域总云量和低云量分布变化.气象, 2012, 38(1):90-95. doi:  10.7519/j.issn.1000-0526.2012.01.010
    [2]
    葛全胜, 王绍武, 方修琦.气候变化研究中若干不确定性的认识问题.地理研究, 2010, 29(2):191-203. http://www.cnki.com.cn/Article/CJFDTOTAL-DLYJ201002002.htm
    [3]
    刘健, 张里阳.气象卫星高空间分辨率数据的云量计算与检验.应用气象学报, 2011, 22(1):35-45. doi:  10.11898/1001-7313.20110104
    [4]
    盛裴轩, 毛节泰, 李建国.大气物理学.北京:北京大学出版社, 2003:444-445.
    [5]
    杨俊, 吕伟涛, 马颖.基于自适应阈值的地基云自动检测方法.应用气象学报, 2009, 20(6):713-721. doi:  10.11898/1001-7313.20090609
    [6]
    高太长, 刘磊, 赵世军.全天空测云技术现状及进展.应用气象学报, 2010, 21(1):101-109. doi:  10.11898/1001-7313.20100114
    [7]
    Shields J E, Karr M E, Tooman T P, et al.The Whole Sky Imager—A Year of Progress.Eighth Atmospheric Radiation Measurement Science Team Meeting.1998. http://citeseerx.ist.psu.edu/viewdoc/summary?cid=2848244
    [8]
    Long C N, Slater D W, Tooman T.Total Sky Imager Model 880 Status and Testing Results.ARM, TR-006, 2001. http://www.osti.gov/scitech/biblio/1020735-total-sky-imager-model-status-testing-results
    [9]
    霍娟, 吕达仁.全天空数字相机观测云量的初步研究.南京气象学报, 2002, 25(2):242-246. http://www.cnki.com.cn/Article/CJFDTOTAL-NJQX200202014.htm
    [10]
    朱彦良. 地基天空红外亮温的观测资料分析. 北京: 中国科学院大气物理研究所, 2005.
    [11]
    Genkova I, Long C N, Besnard T, et al.Assessing Cloud Spatial and Vertical Distribution with Infrared Cloud Analyzer.Fourteenth ARM Science Team Meeting Proceedings.2004. https://www.researchgate.net/publication/237332660_Assessing_Cloud_Spatial_and_Vertical_Distribution_with_Infrared_Cloud_Analyzer
    [12]
    孙学金. 云的地基全天空红外遥感研究. 北京: 北京大学物理学院大气科学系, 2009.
    [13]
    Liou K N. 大气辐射导论. 郭彩丽, 周诗健, 译. 北京: 气象出版社, 2004: 122-127.
    [14]
    章文星, 吕达仁, 常有礼.地基热红外亮温遥感云底高度可行性的模拟研究.地球物理学报, 2007, 50(2):354-363. http://www.cnki.com.cn/Article/CJFDTOTAL-DQWX200702003.htm
    [15]
    胡树贞, 马舒庆, 陶法, 等.地基双波段测云系统及其对比试验.应用气象学报, 2012, 23(4):441-450. doi:  10.11898/1001-7313.20120407
    [16]
    章文星, 吕达仁, 宣越健, 等.利用扫描式红外亮温仪对天空云量的试验观测.气象学报, 2010, 68(6):808-821. doi:  10.11676/qxxb2010.077
    [17]
    孙学金, 刘磊, 高太长, 等.基于模糊纹理光谱的全天空红外图像云分类.应用气象学报, 2009, 20(2):157-163. doi:  10.11898/1001-7313.20090204
    • Relative Articles
    • Supplements(0)
    • Cited By
  • 加载中
  • -->

Catalog

    Figures(10)

    Get Citation
    PDF
    XML
    Article views (3349) PDF downloads(2675) Cited by()
    • Received : 2012-06-28
    • Accepted : 2012-12-26
    • Published : 2013-04-30
    Journal Online
    Contact

    © 2020 Journal of Applied Meteorological Science   京ICP备15006967号-1

    Supported by Beijing Renhe Information Technology Co. Ltd

    /

    DownLoad:  Full-Size Img  PowerPoint
    Return