= uvi_20231118_201512-202305 Cloud-top "wind" data obtained from UVI images used in a published paper Released on 2024-01-18 Produced by: Takeshi Horinouchi == Source data and tool - Source of the data: - UVI public data during 2015-12-07 to 2022-06-09 - UVI data of internal release version(s) - v20230701 for data during 2022-06-09 to 2023-05-31 - Tool used to derive cloud motion vector - Cloud tracking program: al3ct v1.0 hgtag:6c2f21377e68fc783a76f848d958332f0586f739 == Contents File size File name MD5SUM 1036914276 concat_283_eps20_pphvlen2_LT.nc 2f7e90975640256317f9788b7c250c7b 1036246840 concat_365_eps20_pphvlen2_LT.nc 2be86a50dec61da0295530cb16053a42 237668396 daily_uvi_nmin3_283_eps20_pp0hvlen2.0_LT.nc 00a5db28ed0c028820e4e414e7626768 237668396 daily_uvi_nmin3_365_eps20_pp0hvlen2.0_LT.nc 324b4b9d33509e7b79912ac5b71b16b4 File name convention: concat_WWW_epsXX_pphvlenA_LT.nc daily_uvi_nmin3_WWW_epsXX_pp0hvlenA_LT.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) A = 2 or 2.0 : The parameter alpha in the post-process described in Horinouchi et al (2017) == 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 are produced for and described in Horinouchi et al. (2024). Please read the paper for the parameter settings. [This is an extended data product succeeding an earlier publication of Horinouchi et al (2018) that reported mean winds obtained from UVI, but sligt modification in parameter settings was made as described in Horinouchi et al. (2024).] == See also Previous release: ../uvi_20190903_201512-201812 == References If you write a paper by using the data, we hope that the following 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 - Horinouchi, T., Kouyama, T., Imai, M., Murakami, S., Lee, Y. J., Yamazaki, A., Yamada, M., Watanabe, S., Imamura, T., Peralta, J., and Satoh., T. (2024), Long-Term Variability of Mean Winds and Planetary-scale Waves around Venusian Cloud Top Observed with Akatsuki/UVI. Journal of Geophysical Research: Planets, submitted. == File contents summary Example of the "ncdump -h" outputs. % ncdump -h concat_283_eps20_pphvlen2_LT.nc netcdf concat_283_eps20_pphvlen2_LT { dimensions: LT = 66 ; latitude = 60 ; time = 10875 ; variables: double LT(LT) ; LT:long_name = "local time" ; LT:units = "hours" ; LT:modulo = 24. ; 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" ; float longitude(time, LT) ; longitude:long_name = "longitude" ; longitude:units = "degrees_east" ; float U(time, latitude, LT) ; U:long_name = "zonal velocity" ; U:units = "m s-1" ; U:missing_value = -6.e+36f ; U:coordinates = "longitude" ; float V(time, latitude, LT) ; V:long_name = "meridional velocity" ; V:units = "m s-1" ; V:missing_value = -6.e+36f ; V:coordinates = "longitude" ; float C(time, latitude, LT) ; C:long_name = "max. correlation coeff." ; C:units = "1" ; C:missing_value = -999.f ; C:coordinates = "longitude" ; float eps(time, latitude, LT) ; eps:long_name = "estimated accuracy of the winds" ; eps:units = "m s-1" ; eps:missing_value = -6.e+36f ; eps:coordinates = "longitude" ; float epsu(time, latitude, LT) ; epsu:long_name = "max(eps1u,eps2u)" ; epsu:units = "m s-1" ; epsu:missing_value = -6.e+36f ; epsu:coordinates = "longitude" ; float epsv(time, latitude, LT) ; epsv:long_name = "max(eps1v,eps2v)" ; epsv:units = "m s-1" ; epsv:missing_value = -6.e+36f ; epsv:coordinates = "longitude" ; 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 = "2023-07-15 03:40:32 JST horinout> concat_cmv.rb wrote U\n", "2023-07-15 03:40:33 JST horinout> concat_cmv.rb wrote V\n", "2023-07-15 03:40:34 JST horinout> concat_cmv.rb wrote C\n", "2023-07-15 03:40:35 JST horinout> concat_cmv.rb wrote eps\n", "2023-07-15 03:40:37 JST horinout> concat_cmv.rb wrote epsu\n", "2023-07-15 03:40:38 JST horinout> concat_cmv.rb wrote epsv\n", "2023-07-15 03:40:40 JST horinout> concat_cmv.rb wrote S_SOLLON\n", "2023-07-15 03:40:40 JST horinout> concat_cmv.rb wrote S_SOLLAT\n", "2023-07-15 03:40:41 JST horinout> concat_cmv.rb wrote S_SSCLON\n", "2023-07-15 03:40:42 JST horinout> concat_cmv.rb wrote S_SSCLAT\n", "2023-07-15 03:40:43 JST horinout> concat_cmv.rb wrote S_SSCLT\n", "2023-07-15 03:40:44 JST horinout> concat_cmv.rb wrote S_TGRADI\n", "2023-07-15 03:40:45 JST horinout> concat_cmv.rb wrote S_DIST\n", "2023-07-15 03:40:46 JST horinout> concat_cmv.rb wrote S_VSDIST\n", "2023-07-15 03:40:47 JST horinout> concat_cmv.rb wrote S_CLDALT" ; }