All Time Past Year Past 30 Days
Abstract Views 9 0 0
Full Text Views 4518 186 134
PDF Downloads 4215 157 108

Observations of clouds, aerosols, precipitation, and surface radiation over the Southern Ocean: An overview of CAPRICORN, MARCUS, MICRE and SOCRATES

View More View Less
  • 1 1Cooperative Institute for Mesoscale Meteorological Studies, University of Oklahoma, Norman, OK
  • | 2 2School of Meteorology, University of Oklahoma, Norman, OK
  • | 3 3Department of Atmospheric Sciences, University of Washington, Seattle, WA
  • | 4 4Australian Bureau of Meteorology, Melbourne, Australia
  • | 5 5Australian Antarctic Programme Partnership, Institute for Marine and Antarctic Science, University of Tasmania, Hobart, Australia
  • | 6 6Department of Atmospheric Science, Colorado State University, Fort Collins, CO
  • | 7 7Australian Antarctic Division, Hobart, Australia
  • | 8 8Scripps Institution of Oceanography, La Jolla, CA
  • | 9 8bCentre National de Recherches Météorologiques, UMR3589, Toulouse, France
  • | 10 9NorthWest Research Associates, Redmond, WA
  • | 11 10Department of Atmospheric and Oceanic Sciences, University of Colorado, Boulder, CO
  • | 12 11School of Earth, Atmosphere and Environment, Monash University, Melbourne, Australia
  • | 13 12School of Earth Sciences, University of Melbourne, Melbourne, Australia
  • | 14 13Department of Atmospheric Sciences, University of Illinois, Urbana, IL
  • | 15 14National Center for Atmospheric Research, Boulder, CO
  • | 16 15University of Utah, Salt Lake City, UT
  • | 17 16Department of Atmospheric Sciences, Pusan National University, Busan, South Korea
  • | 18 17Karlsruhe Institute of Technology, Karlsruhe, Germany
  • | 19 18Climate Science Centre, Oceans and Atmosphere, CSIRO, Melbourne, Australia
  • | 20 19School of Earth and Atmospheric Sciences, Queensland University of Technology, Brisbane, Australia
  • | 21 20NOAA, Boulder, Colorado
  • | 22 21Beijing Normal University, Beijing, China
  • | 23 22Handix Scientific, Boulder, Colorado
  • | 24 23Peking University, Beijing, China
  • | 25 24National Institute of Water and Atmospheric Research, Wellington, New Zealand
  • | 26 25Gateway Antarctica, University of Canterbury, Christchurch, New Zealand
  • | 27 26School of Physical and Chemical Sciences, University of Canterbury, Christchurch, New Zealand
Full access

Abstract

Weather and climate models are challenged by uncertainties and biases in simulating Southern Ocean (SO) radiative fluxes that trace to a poor understanding of cloud, aerosol, precipitation and radiative processes, and their interactions. Projects between 2016 and 2018 used in-situ probes, radar, lidar and other instruments to make comprehensive measurements of thermodynamics, surface radiation, cloud, precipitation, aerosol, cloud condensation nuclei (CCN) and ice nucleating particles over the SO cold waters, and in ubiquitous liquid and mixed-phase cloudsnucleating particles over the SO cold waters, and in ubiquitous liquid and mixed-phase clouds common to this pristine environment. Data including soundings were collected from the NSF/NCAR G-V aircraft flying north-south gradients south of Tasmania, at Macquarie Island, and on the RV Investigator and RSV Aurora Australis. Synergistically these data characterize boundary layer and free troposphere environmental properties, and represent the most comprehensive data of this type available south of the oceanic polar front, in the cold sector of SO cyclones, and across seasons.

Results show a largely pristine environments with numerous small and few large aerosols above cloud, suggesting new particle formation and limited long-range transport from continents, high variability in CCN and cloud droplet concentrations, and ubiquitous supercooled water in thin, multi-layered clouds, often with small-scale generating cells near cloud top. These observations demonstrate how cloud properties depend on aerosols while highlighting the importance of confirmed low clouds were responsible for radiation biases. The combination of models and observations is examining how aerosols and meteorology couple to control SO water and energy budgets.

Corresponding Author: Greg M. McFarquhar, Cooperative Institute for Mesoscale Meteorological Studies, University of Oklahoma 120 David L. Boren Blvd., Norman, OK 73072 mcfarq@ou.edu; 405-325-3041

Abstract

Weather and climate models are challenged by uncertainties and biases in simulating Southern Ocean (SO) radiative fluxes that trace to a poor understanding of cloud, aerosol, precipitation and radiative processes, and their interactions. Projects between 2016 and 2018 used in-situ probes, radar, lidar and other instruments to make comprehensive measurements of thermodynamics, surface radiation, cloud, precipitation, aerosol, cloud condensation nuclei (CCN) and ice nucleating particles over the SO cold waters, and in ubiquitous liquid and mixed-phase cloudsnucleating particles over the SO cold waters, and in ubiquitous liquid and mixed-phase clouds common to this pristine environment. Data including soundings were collected from the NSF/NCAR G-V aircraft flying north-south gradients south of Tasmania, at Macquarie Island, and on the RV Investigator and RSV Aurora Australis. Synergistically these data characterize boundary layer and free troposphere environmental properties, and represent the most comprehensive data of this type available south of the oceanic polar front, in the cold sector of SO cyclones, and across seasons.

Results show a largely pristine environments with numerous small and few large aerosols above cloud, suggesting new particle formation and limited long-range transport from continents, high variability in CCN and cloud droplet concentrations, and ubiquitous supercooled water in thin, multi-layered clouds, often with small-scale generating cells near cloud top. These observations demonstrate how cloud properties depend on aerosols while highlighting the importance of confirmed low clouds were responsible for radiation biases. The combination of models and observations is examining how aerosols and meteorology couple to control SO water and energy budgets.

Corresponding Author: Greg M. McFarquhar, Cooperative Institute for Mesoscale Meteorological Studies, University of Oklahoma 120 David L. Boren Blvd., Norman, OK 73072 mcfarq@ou.edu; 405-325-3041
Save