Summary: Mixed-phase clouds over the Southern Ocean present a significant challenge for climate models, which predict too much ice and too few liquid water. This bias leads to substantial errors in estimating the Earth’s energy balance. To address this, I’m replacing the current simplified temperature-dependent ice nucleating particle (INP) parameterization with a more physically grounded approach that links ice formation to aerosols. I will implement the parameterizations from McCluskey et al. (2018) and Wilson et al. (2015), which calculates INP concentrations based on the amount of sea spray and marine organic aerosol. I will perform two 7-day high-resolution simulations at 1.5 km using the UM RNS RAL3p2 configuration (CASIM + UKCA). The results will be compared with observations collected from the CAPRICORN II voyage.
People: Zhangcheng Pei, Sonya Fiddes, Marc Mallet, Matthew Woodhouse, Kalli Furtado, Alain Protat, Simon Alexander
Model: UM Regional Nesting Suite
Configuration: RAL3p2, 1.5 km resolution, 400x800 grids, 10-minute output, 7 days.
Experiments:
- McCluskey et al. (2018) INP parameterization
- Wilson et al. (2015) INP parameterization
Total KSUs required: 80 KSU
Total storage required: No storage required