= uvi_20181010_Horinouchi2018 Cloud-top "wind" data obtained from UVI images used in a published paper Released on 2018-10-10 to the Akatsuki Science Working Team members Produced by: Takeshi Horinouchi == Source data and tool - Source of the data: - UVI data of internal release version v20170601 - Tool used to derive cloud motion vector - Cloud tracking program: al3ct v1.0 hgtag:6c2f21377e68fc783a76f848d958332f0586f739 == Contents File size File name MD5SUM 173021132 concat_283_eps10_pphvlen1.nc 77f3e59f2345c2e3e8a841dcffe5bb43 173021132 concat_283_eps20_pphvlen1.nc ba4633fdd2c63f118741fe39703ed4ae 171984068 concat_365_eps10_pphvlen1.nc 3a084c725dce8c014702b9215f6d0cdf 171984068 concat_365_eps20_pphvlen1.nc 92f198e36760df67c105a831149bc1ae File name convention: concat_WWW_epsXX_pphvlen1.nc WWW = 283 or 365 : UVI filter wavelength (nm) XX = 10 or 20 : Value of the precision screening parameter epsilon in Ikegawa and Horinouchi (m/s) == Description Cloud tracking was conducted by using an automated method described in Ikegawa and Horinouchi (2016) and Horinouchi et al (2017). 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 Horinouchi et al (2017). The data in this directory were produced for and used in Horinouchi et al (2018). Please read the paper for the parameter settings. == References If you write a paper by using the data, we hope that the following three papers and the data set are cited: - 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 - 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 - Horinouchi, T., T. Kouyama, Y. J. Lee, S. Murakami, K. Ogohara, M. Takagi, T. Imamura,K. Nakajima, J. Peralta, A. Yamazaki, M. Yamada, S. Watanabe (2018), Mean winds at the cloud top of Venus obtained from two-wavelength UV imaging by Akatsuki, Earth, Planets and Space, 70:10, https://doi.org/10.1186/s40623-017-0775-3 - 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 Example of the "ncdump -h" outputs. ncdump -h concat_283_eps10_pphvlen1.nc netcdf concat_283_eps10_pphvlen1 { dimensions: longitude = 120 ; latitude = 60 ; time = 1001 ; 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" ; // global attributes: :history = "2017-12-25 13:30:08 JST horinout> concat_cmv.rb wrote U\n", "2017-12-25 13:30:08 JST horinout> concat_cmv.rb wrote V\n", "2017-12-25 13:30:08 JST horinout> concat_cmv.rb wrote C\n", "2017-12-25 13:30:08 JST horinout> concat_cmv.rb wrote eps\n", "2017-12-25 13:30:08 JST horinout> concat_cmv.rb wrote epsu\n", "2017-12-25 13:30:08 JST horinout> concat_cmv.rb wrote epsv\n", "2017-12-25 13:30:08 JST horinout> concat_cmv.rb wrote S_SOLLON\n", "2017-12-25 13:30:08 JST horinout> concat_cmv.rb wrote S_SOLLAT\n", "2017-12-25 13:30:08 JST horinout> concat_cmv.rb wrote S_SSCLON\n", "2017-12-25 13:30:08 JST horinout> concat_cmv.rb wrote S_SSCLAT\n", "2017-12-25 13:30:09 JST horinout> concat_cmv.rb wrote S_SSCLT\n", "2017-12-25 13:30:09 JST horinout> concat_cmv.rb wrote S_TGRADI\n", "2017-12-25 13:30:09 JST horinout> concat_cmv.rb wrote S_DIST" ; }