Near-surface specific humidity data obtained from T-PARCII dropsonde observations

Description This dataset consists of near-surface specific humidity data obtained from dropsonde observations conducted during the Tropical cyclones–Pacific Asian Research Campaign for Improvement of Intensity Estimations/Forecast (T-PARCII). The dataset was organized by Hiroyuki Tomita for the validation of satellite-based estimates. It contains values derived from a total of 86 profiles obtained during observations of Typhoons Lan (2017) and Trami (2018). Only the lowest level of each dropsonde water vapor profile was used. The observed near-surface specific humidity values at this level were adjusted to 10 m height using J-OFURO3 satellite-estimated SST (Tomita et al., 2019) together with the COARE 3.0 bulk algorithm (Fairall et al., 2003). File names and variable names and their descriptions are listed below. File names sfc_Lan_2017_hc_qa.csv sfc_Trami_2018_hc_qa.csv Variables Variable name: Desctiption (unit) sounding id: serial id of soundings for each Typhoon sec: duration (second) yyyy: year mm: month dd: day h:m:s sec: time (UTC) lat: latitude (degree N) lon: longitude (degree E) gpm: geopotential height (m) QA10: converted specific humidity at 10 m height (g/kg) SST: J-OFURO3 sea surface temperature (deg.C) Note In some soundings, gpm exceeds 1000 m; in such cases, the QA10 values should be disregarded. It has been reported that the relative humidity data observed during this period of the T-PARCII campaign are affected by a dry bias (Kanada et al., 2024). At present, no specific corrections or adjustments have been applied to address this issue. Caution should therefore be exercised when using these data for research purposes. Reference Fairall, C. W., E. F. Bradley, J. E. Hare, A. A. Grachev, and J. B. Edson (2003), Bulk parameterization of air‒sea fluxes: updates and verification for the COARE algorithm, Journal of Climate, 16(4), 571‒591, doi:10.1175/1520-0442(2003)016<0571:BPOASF>2.0.CO;2. Kanada, S., M. Kato, K. Tsuboki, T. Ohigashi, S. Hirano, K. Shimizu, R. Nozawa, A. Yoshimura, Y. Goto, and K. Tsukagoshi, 2024: Evaluation of newly developed dropsonde for aircraft observation. SOLA, 20, 378−385, doi:10.2151/sola.2024-050 T-PARCII: http://www.rain.hyarc.nagoya-u.ac.jp/~tsuboki/kibanS/index_kibanS_eng.html Tomita, H., T. Hihara, S. Kako, M. Kubota, and K. Kutsuwada,2019: An introduction to J-OFURO3, a third-generation Japanese ocean flux data set using remote-sensing observations, Journal of Oceanography, 75(2), 171‒194, https://doi.org/10.1007/s10872-018-0493-x Acknowledgments The T-PARCII data were kindly provided by Prof. Kazuhisa Tsuboki of Nagoya University. We are also grateful to Dr. Sachie Kanadani of Nagoya University for providing technical information on the dropsonde observations.