Log-Profile Analysis of the Near-Surface Layer and Air-Sea Turbulent Fluxes in Hurricanes Using Dropsondes

Details

• Journal Title:
  Journal of Atmospheric and Oceanic Technology
• Personal Author:
  Wallace, Daniel E. ; Bourassa, Mark A. ; Holbach, Heather M. ; Bryan, Amelia ; Yang, Sinil ; Kim, Baek-Min
• NOAA Program & Office:
  OAR (Oceanic and Atmospheric Research) ; AOML (Atlantic Oceanographic and Meteorological Laboratory) ; NGI (Northern Gulf Institute)
• Description:
  Data collected from individual dropsondes within tropical cyclones are analyzed to better understand the near-surface profiles of wind speed, potential temperature, and humidity. The resulting fitting parameters are used to estimate surface fluxes of momentum, sensible heat, and latent heat within tropical cyclones. Vertical offsets of the profiles are calculated and described. Our methodology accounts for these offsets through a displacement height for each profile. Of 915 dropsonde profiles visually examined, 42.3% appeared to have log-like near-surface profiles. Good matches to theoretical profiles were found with only 95 (10.4%) profiles (25% of profiles that had data in the layer of interest). The boundary layer variables that we determine from an individual dropsonde are noisy because dropsondes do not capture a good sample of the mean boundary layer. Despite the weaknesses, means and medians constructed from the collection of processed dropsondes can be used to estimate values of boundary layer variables within tropical cyclones. Our analysis produces wind speed-dependent median boundary layer values within a range of uncertainty determined from the observations. Examples of the profiles, displacement heights, fluxes, drag coefficients, and the abovementioned problems are presented.
• Source:
  Journal of Atmospheric and Oceanic Technology, 43(7), 825-842
• DOI:
  https://doi.org/10.1175/JTECH-D-24-0002.1
• ISSN:
  0739-0572 ; 1520-0426
• Format:
  PDF
• Publisher:
  American Meteorological Society
• Document Type:
  Journal Article
• Funding:
  Grant no. NA16OAR4320199 ; Grant no. NA21OAR4320190
• Rights Information:
  Other
• Compliance:
  Submitted
• Main Document Checksum:
  urn:sha-512:442bd0104fb892b567d30b06fd3262eec635d66a6cf449e9fe779393ba5ec36b7ab88470ca4b3c6e2d8230db1db5bbc141e52be1732d44f659a2c476d899ea87
• Download URL:
  https://repository.library.noaa.gov/view/noaa/74019/noaa_74019_DS1.pdf
• File Type:
  [PDF - 8.74 MB ]