In Situ and remote sensing of aerosol properties and their influences in tropical oceanic warm rain systems

This study includes two parts. First, in-situ aerosol particulates with size below 2.5 microns (PM25) observations are collected from the Nueces headwaters to the Texas coast, ending in Nueces Bay in April 2023. The potential links between parameters involved in the atmospheric and aerosol samples are examined. The second part focuses on examining the relationships between the properties of oceanic warm rain systems and aerosols by using remotely sensed observations. By utilizing the Navy Aerosol Analysis and Prediction System (NAAPS) AOD reanalysis product, collocated with Global Precipitation Measurement (GPM) data from 2014-2022, we examine the relationships between the aerosol types and concentrations and properties of warm rain systems over the Eastern Pacific and the Central Atlantic. The warm rain systems are selected by maximum echo top heights less than 5 km and size smaller than ~250 km2. Over the Central Atlantic, dust particles are the most abundant aerosol and peak in JJA with the emergence of the Saharan Air Layer. Over the Eastern Pacific, smoke and sulfate tend to be the most abundant particles with both peaking in MAM. We also examined the relationships between AOD and the properties of warm rain under different large-scale descent and near surface air temperature environments collocated from ERA5 reanalysis product. This study suggests the type of aerosol as well as large scale thermodynamic environmental parameters are important when understanding the relationship between aerosols and warm precipitation. However, the overall influence of aerosols in these systems does not seem to be significant based on the statistically analysis.