Structure of an Atmospheric River Over Australia and the Southern Ocean: II. Microphysical Evolution

Details

• Journal Title:
  Journal of Geophysical Research: Atmospheres
• Personal Author:
  Finlon, Joseph A. ; Rauber, Robert M. ; Wu, Wei ; Zaremba, Troy J. ; McFarquhar, Greg M. ; Nesbitt, Stephen W. ; Schnaiter, Martin ; Järvinen, Emma ; Waitz, Fritz ; Hill, Thomas C. J. ; DeMott, Paul J.
  More +
• NOAA Program & Office:
  CIMMS (Cooperative Institute for Mesoscale Meteorological Studies)
• Description:
  An atmospheric river affecting Australia and the Southern Ocean on 28–29 January 2018 during the Southern Ocean Clouds, Radiation, Aerosol Transport Experimental Study (SOCRATES) is analyzed using nadir-pointing W-band cloud radar measurements and in situ microphysical measurements from a Gulfstream-V aircraft. The AR had a two-band structure, with the westernmost band associated with a cold frontal boundary. The bands were primarily stratiform with distinct radar bright banding. The microphysical evolution of precipitation is described in the context of the tropical- and midlatitude-sourced moisture zones above and below the 0°C isotherm, respectively, identified in Part I. In the tropical-sourced moisture zone, ice particles at temperatures less than −8°C had concentrations on the order of 10 L−1, with habits characteristic of lower temperatures, while between −8°C and −4°C, an order of magnitude increase in ice particle concentrations was observed, with columnar habits consistent with Hallett-Mossop secondary ice formation. Ice particles falling though the 0°C level into the midlatitude-sourced moisture region and melting provided “seed” droplets from which subsequent growth by collision-coalescence occurred. In this region, raindrops grew to sizes of 3 mm and precipitation rates averaged 16 mm hr−1.
• Source:
  Journal of Geophysical Research: Atmospheres, 125, e2020JD032514
• DOI:
  https://doi.org/10.1029/2020JD032514
• Document Type:
  Journal Article
• Rights Information:
  Other
• Compliance:
  Submitted
• Download URL:
  https://repository.library.noaa.gov/view/noaa/31636/noaa_31636_DS1.pdf
• File Type:
  [PDF - 4.01 MB]
• Collection(s):
  NOAA Cooperative Institutes
• Main Document Checksum:
  urn:sha-512:db1d0aac74dc8a39bb4c6d0342d393442bf95051a29fd9a44252d5bbbbfdaaadc1411ab47d774688014ac4d62eb565d2ce5d48ae6dc80c50d1684ee728225a4a