The Analysis and Correction of Lunar Intrusion to Space View of FY-3A/MWHS

Gu Songyan; Wu Ronghua; You Ran

doi:10.11898/1001-7313.20150406

Vol.26, NO.4, 2015

Turn off MathJax

Article Contents

Article Navigation > Journal of Applied Meteorological Science > 2015 > 26(4): 442-450

Gu Songyan, Wu Ronghua, You Ran. The analysis and correction of lunar intrusion to space view of FY-3A/MWHS. J Appl Meteor Sci, 2015, 26(4): 442-450. DOI: 10.11898/1001-7313.20150406.

Citation:

Gu Songyan, Wu Ronghua, You Ran. The analysis and correction of lunar intrusion to space view of FY-3A/MWHS. J Appl Meteor Sci, 2015, 26(4): 442-450. DOI: 10.11898/1001-7313.20150406.

Gu Songyan, Wu Ronghua, You Ran. The analysis and correction of lunar intrusion to space view of FY-3A/MWHS. J Appl Meteor Sci, 2015, 26(4): 442-450. DOI: 10.11898/1001-7313.20150406.

Citation:

Gu Songyan, Wu Ronghua, You Ran. The analysis and correction of lunar intrusion to space view of FY-3A/MWHS. J Appl Meteor Sci, 2015, 26(4): 442-450. DOI: 10.11898/1001-7313.20150406.

PDF( 1474 KB)

The Analysis and Correction of Lunar Intrusion to Space View of FY-3A/MWHS

DOI: 10.11898/1001-7313.20150406

The Key Laboratory of Radiometric Calibration and Validation for Environmental Satellites, China Meteorological Administration (LRCVES/CMA), National Satellite Meteorological Center, Beijing 100081

Received Date: 2014-12-30
Rev Recd Date: 2015-03-31
Publish Date: 2015-07-31

Abstract

Abstract

The microwave humidity sounder (MWHS) is an important payload of FY-3A launched on 27 May 2008, for global all-weather atmosphere sounding. FY-3A/MWHS has been in operational application on orbit for more than 5 years. FY-3A/MWHS has five channels in the range of 150-191 GHz. In the normal working mode, it performs a cross-track scanning and cycle two points calibration by using of the blackbody and space views. However, the moon may occasionally appear within the cold space calibration field of view. Due to the polar orbit of the platform, it will always appear to be near the-90 phase and then have a brightness temperature of approximately 170-200 K. Its angular extent is about 0.5. Lunar radiation could therefore be significant against a cold sky background, especially for the narrow-beamed MWHS. Lunar intrusion to space view of MWHS may make a moon-glint, which typically affects about 100 scan lines per orbit for 4-5 consecutive orbits. Lunar intrusion cases are detectable as the degradation in NWP model statistics.Based on analysis of lunar intrusion cases and effects, a mitigation algorithm is developed to improve calibration results of FY-3A/MWHS in orbit.In the algorithm, the position of the moon is calculated using standard astronomical formula, and the intruding time is flagged. After that an approximation by polynomial model is devised to remove the moon-glint. On 4 July 2010, the moon-glint makes more than 1000 digital number abnormal jumping, and 20 degree degradation in brightness at sub-points line for FY-3A/MWHS 183.31±1 GHz channel.By using of the cross calibration technique between corresponding channels of FY-3/MWHS and MetOp-A/MHS, an extensive analysis is carried out to make the best fitted global SNO samples.The lunar intrusion mitigation algorithm is tested, and results show that after removing the moon-glint effects, corrected calibration results are almost the same with what got during check in orbit. The lunar intrusion mitigation algorithm works well and has been used in operation, providing the foundation of quantitative application for data of FY-3A/MWHS in NWP. Lunar intrusion also gives a clear view of the moon when it appears in the field of space view. Since there is no intervening atmosphere to attenuate the signal, which makes it possible to perform a cross-channel calibration.
- microwave humidity sounder;
- radiation calibration;
- lunar intrusion;
- polynomial correction model

FullText(HTML)

References(16)

Figures and Tables

图 1 月球对微波湿度计冷空观测影响实际数据对比

(a) 正常情况下冷空观测数据，(b) 正常情况下黑体观测数据，(c) 受到月球影响的冷空观测数据，(d) 与图 1c对应的黑体观测数据

Fig. 1 Impact on space view from moon-glint

(a) space view, (b) black body view, (c) space view contaminated by moon-glint, (d) black body view matching with Fig. 1c

DownLoad: Full-Size Img PowerPoint

图 2 月球影响过程中扫描线间冷空观测数据变化情况

Fig. 2 The change of space view data between scan-lines during a moon-glint

DownLoad: Full-Size Img PowerPoint

图 3 接收机增益和仪器温度变化特性

Fig. 3 The basic data distribution during an orbit observation

DownLoad: Full-Size Img PowerPoint

图 4 2008年7月22日微波湿度计183±1 GHz通道冷空观测数据连续多轨分布

Fig. 4 The distribution of space view data for FY-3A/MWHS 183.31±1 GHz channel over orbits on 22 Jul 2008

DownLoad: Full-Size Img PowerPoint

图 5 风云三号卫星微波湿度计受月球影响示意图

(a)月球进入微波湿度计冷空观域示意图，(b)月球对卫星视张角

Fig. 5 Sketch map of FY-3/MWHS affected by the moon

(a) Scanning sketch map of FY-3/MWHS when the moon in space area，(b) moon solid angle to FY-3 satellite center

DownLoad: Full-Size Img PowerPoint

图 6 月球影响微波湿度计定标示意图

Fig. 6 Sketch map of how the moon affecting on the FY-3A/MWHS space view

DownLoad: Full-Size Img PowerPoint

图 7 星下点对地观测亮温变化

(a) 星下点亮温，(b) 星下点计数值，(c) 冷空观测计数值

Fig. 7 Brightness temperature for sub-points during an orbit observation

(a) brightness temperatures for sub-point lines，(b) earth views for sub-point lines，(c) space views

DownLoad: Full-Size Img PowerPoint

References

[1]	Vinnikov K Y, Grody N C.Global warming trend of mean tropospheric temperature observed by satellite.Science, 2003, 302(5643):269-272. doi: 10.1126/science.1087910
[2]	Lu Q F.Initial evaluation and assimilation of FY-3A atmospheric sounding data in the ECMWF System.Sci China Earth Sci, 2011, 54:1453-1457, doi: 10.1007/s11430-011-4243-9.
[3]	张升伟, 李靖, 姜景山, 等.风云3号卫星微波湿度计的系统设计与研制.遥感学报, 2008, 12(2):199-207. http://www.cnki.com.cn/Article/CJFDTOTAL-YGXB200802002.htm
[4]	Zhang Shengwei, Li Jing, Wang Zhenzhan.Design of the Second Generation Microwave Humidity Sounder (MWHS-Ⅱ) for Chinese Meteorological Satellite FY-3.Geoscience and Remote Sensing Symposium (IEEE International Geoscience and Remote Sensing Symposium IGARSS), IEEE International, ISSN:2153-6996, 2012:4672-4675.
[5]	Jing Li, Zhang Shengwei, Jiang Jingshan, et al.In-orbit Performance of Microwave Humidity Sounder (MWHS) of the Chinese FY-3 Meteorological Satellite.Geoscience and Remote Sensing Symposium (IEEE International Geoscience and Remote Sensing Symposium IGARSS), IEEE International, ISSN:2153-6996, 2010:574-577.
[6]	谷松岩, 王振占, 李靖, 等.FY-3A/MWHS在轨定标及结果分析.中国工程科学, 2013, 15(7):92-100. http://www.cnki.com.cn/Article/CJFDTOTAL-GCKX201307013.htm
[7]	Gu Songyan, Guo Yang, Wang Zhenzhan, et al.Calibration analyses for sounding channels of MWHS onboard FY-3A.IEEE Transaction on Geoscience and Remote Sensing, 2012, 50(12):4885-4891. doi: 10.1109/TGRS.2012.2214391
[8]	NOAA Satellite and Information Service.NOAA KLM User's Guide (Satellite and data description of NOAA's Polar orbiting satellites from NOAA-15 and later).http://www.ncdc.noaa.gov/oa/pod-guide/ncdc/docs/klm/index.htm, 2009.
[9]	JPL, Airs Project Algorithm Theoretical Basis Document Part 3:Microwave Instruments, JPL D-17005, Version 2.1, 2000.
[10]	谷松岩, 王振占, 李靖, 等.风云三号A星微波湿度记住探测通道辐射特性.应用气象学报, 2010, 21(3):335-342. doi: 10.11898/1001-7313.20100309
[11]	窦芳丽, 卢乃锰, 谷松岩.星载双频风场雷达热带气旋降雨区测风模拟.应用气象学报, 2012, 23(4):467-477. doi: 10.11898/1001-7313.20120410
[12]	郭杨, 卢乃锰, 谷松岩.毫米/亚毫米波探测大气温度和湿度的通道选择.应用气象学报, 2010, 21(6):716-723. doi: 10.11898/1001-7313.20100608
[13]	游然, 卢乃锰, 邱红, 等.用PR资料分析热带气旋卡特里娜降水特征.应用气象学报, 2011, 22(2):89-95. http://qikan.camscma.cn/jams/ch/reader/view_abstract.aspx?file_no=20110209&flag=1
[14]	邱红, 方翔, 谷松岩, 等.利用AMSU分析热带气旋结构特征.应用气象学报, 2007, 18(6):810-820. doi: 10.11898/1001-7313.200706123
[15]	刘志权, 张凤英, 吴雪宝, 等.区域极轨卫星ATOVS辐射偏差订正方法研究.气象学报, 2007, 65(1):115-123. http://www.cnki.com.cn/Article/CJFDTOTAL-QXXB200701010.htm
[16]	Weng F, Zou X, Sun N, et al.Calibration of Suomi national polarorbiting partnership advanced technology microwave sounder.J Geophys Atmos, 2013, 118:187-200, doi: 10.1002/jgrd.50840.