= ir2_20190413_Horinouchi2017 Cloud motion vectors obtained from IR2 nightside images (2.26um) used in a published paper Released on 2019-04-13 to the Akatsuki Secience Working Team members. Produced by: Takeshi Horinouchi = Source data and tool - Source of the data: - IR2 L2 data of internal release version 0.2.1 (Note: L3 data product was not used; bore-sight correction was done separately) - Tool used to derive cloud motion vector - Cloud tracking program: al3ct v1.0 hgtag:6c2f21377e68fc783a76f848d958332f0586f739 == Contents + Pre-screend data (recommended). File size File name md5sum 2.9M concat_226_eps15_pphvlen1.5.nc a2a29b1a56f1a590fea53c22ac512ae5 File name convention: concat_WWW_epsXX_pphvlenYYY.nc WWW = 226 : IR2 filter wavelength (2.26 um) XX = 15 : Value of the precision screening parameter epsilon in Ikegawa and Horinouchi (m/s) YYY = 1.5 : The value of alpha in Horinouchi et al (2017a) + Unscreend original outputs. CAUTION: The following data are raw cloud-tracking program outputs, so *** YOU SHOULD FILTER THE DATA BY YOURSELF. *** File size File name 116K ir2_20160325_07-11_174-226_60x60_sON_f3.nc 116K ir2_20160325_07-11_226_60x60_sON_f3.nc 108K ir2_20160415_08-10-12_226_60x60_sON_f3.nc 96K ir2_20160711_12to18dt2_226_60x60_sON_f3.nc 104K ir2_20160711_20to02dt2_226_60x60_sON_f3.nc 112K ir2_20160722_10to16dt2_226_60x60_sON_f3.nc 100K ir2_20160722_12to18dt2_226_60x60_sON_f3.nc 104K ir2_20160722_14to20dt2_226_60x60_sON_f3.nc 112K ir2_20160813_00to06dt2_226_60x60_sON_f3.nc 116K ir2_20160815_11to17dt2_226_60x60_sON_f3.nc 120K ir2_20160825_04to10dt2_226_60x60_sON_f3.nc 120K ir2_20160825_10to16dt2_226_60x60_sON_f3.nc 120K ir2_20160825_16to22dt2_226_60x60_sON_f3.nc 124K ir2_20160826_16to22dt2_226_60x60_sON_f3.nc 124K ir2_20160827_08to14dt2_226_60x60_sON_f3.nc 124K ir2_20160828_12to18dt2_226_60x60_sON_f3.nc 124K ir2_20160905_03to09dt2_226_60x60_sON_f3.nc 124K ir2_20160905_07to13dt2_226_60x60_sON_f3.nc == Description Cloud tracking was conducted by using an automated method described in [1] Ikegawa and Horinouchi (2016) and [2] Horinouchi et al (2017a). Its basic algorithm and quality evaluation method are presented in Ikegawa and Horinouchi (2016), and a further improvement and the data screening method are described in [2] Horinouchi et al (2017a). The data in this directory were produced for and used in [3] Horinouchi et al (2017b). Please read the paper for the parameter settings and the bore-sight correction conducted. == References If you write a paper by using the data, please cite the following three papers ([1] and [2] for the methods and [3] for the bore-sight correction and parameter settings) and the data set [4]: [1] Ikegawa, S., and T. Horinouchi (2016), Improved automatic estimation of winds at the cloud top of Venus using superposition of cross-correlation surfaces, Icarus, 271, 98-119, https://doi.org/10.1016/j.icarus.2016.01.018 [2] Horinouchi, T., S. Murakami T. Kouyama, K. Ogohara, A. Yamazaki, M. Yamada, S. Watanabe (2017), Image velocimetry for clouds with relaxation labeling based on deformation consistency, Measurement Science and Technology, 28(8), 085301 (10pp), https://doi.org/10.1088/1361-6501/aa695c [3] Horinouchi, T., S. Murakami, T. Satoh, J. Peralta, K. Ogohara, T. Kouyama, T. Imamura, H. Kashimura, S. S. Limaye, M. Nakamura, T. M. Sato, K. Sugiyama, M. Takagi, S. Watanabe, M. Yamada, A. Yamazaki, E. F. Young (2017), Equatorial jet in the lower to middle cloud layer of Venus revealed by Akatsuki, Nature Geoscience, 10, 646-651, https://doi.org/10.1038/ngeo3016 [4] Horinouchi, T., S. Murakami, K. Ogohara, T. Kouyama, M. Takagi (2021), Venus Climate Orbiter Akatsuki Cloud Motion Vector Data Set v1.0, JAXA Data Archives and Transmission System, https://doi.org/10.17597/isas.darts/vco-00020 == File contents summary "ncdump -h" output: $ ncdump -h concat_226_eps15_pphvlen1.5.nc netcdf concat_226_eps15_pphvlen1.5 { dimensions: longitude = 120 ; latitude = 60 ; time = 17 ; variables: float longitude(longitude) ; longitude:long_name = "longitude" ; longitude:units = "degrees_east" ; float latitude(latitude) ; latitude:long_name = "latitude" ; latitude:units = "degrees_north" ; double time(time) ; time:long_name = "observation time" ; time:units = "hours since 2000-1-1 00:00:00 UTC" ; time:comment = "average of time variables in input L3a files" ; double lon_lt0(time) ; lon_lt0:long_name = "longitude where LT=0" ; lon_lt0:units = "degrees_east" ; float U(time, latitude, longitude) ; U:long_name = "zonal velocity" ; U:units = "m s-1" ; U:missing_value = -6.e+36f ; U:coordinates = "lon_lt0" ; float V(time, latitude, longitude) ; V:long_name = "meridional velocity" ; V:units = "m s-1" ; V:missing_value = -6.e+36f ; V:coordinates = "lon_lt0" ; float C(time, latitude, longitude) ; C:long_name = "max. correlation coeff." ; C:units = "1" ; C:missing_value = -999.f ; C:coordinates = "lon_lt0" ; float eps(time, latitude, longitude) ; eps:long_name = "estimated accuracy of the winds" ; eps:units = "m s-1" ; eps:missing_value = -6.e+36f ; eps:coordinates = "lon_lt0" ; float epsu(time, latitude, longitude) ; epsu:long_name = "max(eps1u,eps2u)" ; epsu:units = "m s-1" ; epsu:missing_value = -6.e+36f ; epsu:coordinates = "lon_lt0" ; float epsv(time, latitude, longitude) ; epsv:long_name = "max(eps1v,eps2v)" ; epsv:units = "m s-1" ; epsv:missing_value = -6.e+36f ; epsv:coordinates = "lon_lt0" ; float S_SOLLON(time) ; S_SOLLON:long_name = "sub solar longitude" ; S_SOLLON:units = "degrees_east" ; S_SOLLON:comment = "L2 attribute" ; float S_SOLLAT(time) ; S_SOLLAT:long_name = "sub solar latitude" ; S_SOLLAT:units = "degrees_north" ; S_SOLLAT:comment = "L2 attribute" ; float S_SSCLON(time) ; S_SSCLON:long_name = "AKATSUKI sub S/C longitude" ; S_SSCLON:units = "degrees_east" ; S_SSCLON:comment = "L2 attribute" ; float S_SSCLAT(time) ; S_SSCLAT:long_name = "AKATSUKI sub S/C latitude" ; S_SSCLAT:units = "degrees_north" ; S_SSCLAT:comment = "L2 attribute" ; float S_SSCLT(time) ; S_SSCLT:long_name = "AKATSUKI sub S/C local time" ; S_SSCLT:units = "hours" ; S_SSCLT:comment = "L2 attribute" ; float S_TGRADI(time) ; S_TGRADI:long_name = "target radius at sub S/C point" ; S_TGRADI:units = "km" ; S_TGRADI:comment = "L2 attribute" ; float S_DIST(time) ; S_DIST:long_name = "distance between S/C and Venus" ; S_DIST:units = "km" ; S_DIST:comment = "L2 attribute" ; float S_VSDIST(time) ; S_VSDIST:long_name = "Venus-Sun distance" ; S_VSDIST:units = "km" ; S_VSDIST:comment = "L2 attribute" ; float S_CLDALT(time) ; S_CLDALT:long_name = "assumed cloud altitude" ; S_CLDALT:units = "km" ; S_CLDALT:comment = "L2 attribute" ; // global attributes: :history = "2019-04-13 13:23:47 JST horinout> concat_cmv.rb wrote U\n", "2019-04-13 13:23:47 JST horinout> concat_cmv.rb wrote V\n", "2019-04-13 13:23:47 JST horinout> concat_cmv.rb wrote C\n", "2019-04-13 13:23:47 JST horinout> concat_cmv.rb wrote eps\n", "2019-04-13 13:23:47 JST horinout> concat_cmv.rb wrote epsu\n", "2019-04-13 13:23:47 JST horinout> concat_cmv.rb wrote epsv\n", "2019-04-13 13:23:47 JST horinout> concat_cmv.rb wrote S_SOLLON\n", "2019-04-13 13:23:47 JST horinout> concat_cmv.rb wrote S_SOLLAT\n", "2019-04-13 13:23:47 JST horinout> concat_cmv.rb wrote S_SSCLON\n", "2019-04-13 13:23:47 JST horinout> concat_cmv.rb wrote S_SSCLAT\n", "2019-04-13 13:23:47 JST horinout> concat_cmv.rb wrote S_SSCLT\n", "2019-04-13 13:23:47 JST horinout> concat_cmv.rb wrote S_TGRADI\n", "2019-04-13 13:23:47 JST horinout> concat_cmv.rb wrote S_DIST\n", "2019-04-13 13:23:47 JST horinout> concat_cmv.rb wrote S_VSDIST\n", "2019-04-13 13:23:47 JST horinout> concat_cmv.rb wrote S_CLDALT" ; }