Cloud and Drizzle Properties Retrieved from Ship-Based Observations during MAGIC

Abstract:

The Marine ARM GPCI Investigation of Clouds (MAGIC) field campaign provided a wealth of information looking at the stratocumulus to cumulus transition (SCT) over the Eastern-North Pacific (ENP), however, the lack of cloud in-situ measurements still left many cloud microphysical properties unknown. This study uses the methods developed by Wu et. al., 2020, to retrieve cloud and drizzle properties during the MAGIC campaign. Using the W-band ARM cloud radar (WACR), ceilometer, and 3-channel microwave radiometer onboard the ship, the retrieval includes single-layer low-level cloud and drizzle particle size (r_c and r_m,d), number concentration (N_c and N_d), and liquid water content (LWC_c and LWC_d). Mean values of r_c, r_m,d, N_c, N_d, LWC_c, LWC_d are 12.1 μm, 55.8 μm, 97.9 cm^-3, 0.06 cm^-3, 0.40 g m^-3, 0.05 g m^-3, respectfully for the entire MAGIC campaign. Additionally, this study looks at how these properties change with longitude over the ocean with the most noticeable difference being an increase in drizzle size and decrease in cloud particle size moving from California towards Hawaii. This study has provided a more in-depth understanding of cloud processes over the North-East Pacific. With this information, a better understanding of the SCT can be achieved and additionally be used to improve model simulations.