Datasets and Early Results from MARCUS and MICRE

Description

Clouds over the Southern Ocean are poorly represented in present day reanalysis products and global climate model simulations. Errors in top-of-atmosphere broadband radiative fluxes in this region are among the largest globally, with large implications for modeling both regional and global scale climate. This error is largely due to a lack of low cloud in the cold sector of cyclonic systems. The difficulties climate models have in simulating Southern Ocean low clouds was a major impetus behind the ARM supported Measurements of Aerosols, Radiation, and Clouds over the Southern Ocean (MARCUS) experiment and the Macquarie Island Cloud and Radiation Experiment (MICRE). In the MARCUS experiment, an ARM mobile facility was placed aboard the Australian Antarctic Division (AAD) ice-breaker the Aurora Australis during supply voyages to Antarctica and Macquarie Island in 2018; while in MICRE, ARM in coordination with the Australian Bureau of Meteorology and AAD collected observations from Macquarie Island (located at 54.5o S, roughly halfway between Australia and Antarctica) between March 2016 and March 2018. In this poster, an overview of MICRE and MARCUS datasets will be provided along with some early results, including an examination of statistical distributions of cloud and precipitation properties (e.g., liquid water path, cloud base height, cloud top height, boundary layer height, precipitation occurrence and rain rate) as a function of various environmental conditions, as well as in comparison to satellite datasets.