The macrophysical properties of shallow cumulus clouds from moderate- and high-resolution satellite data collected over the tropical western Pacific

Shallow cumulus cloud fields play a very important role in Earth’s global water and energy cycles. Unfortunately, cumulus cloud properties are difficult to quantify using meteorological satellite instruments owing to the fact that shallow cumuli are typically smaller than the measurement resolution of these instruments. This results in retrieved cloud properties that are biased, which can lead to their biased representation in climate models. As such, there is a need to obtain high-resolution observations of shallow cumuli to better understand them. Using high-resolution satellite data and data from field campaigns remains our primary method for accurately retrieving the properties of these small clouds. In this thesis, cumulus cloud fields over the tropical western Pacific are examined using satellite and aircraft data collected during the Cloud, Aerosol and Monsoon Processes Philippines Experiment (CAMP2Ex) mission from August to October 2019. First, the high-resolution Terra-ASTER data collected from CAMP2Ex is used to expand the training set for the MISR resolution corrected cloud fraction product. Results show that the expansion of the training set has little improvement over the operational one. This may be because the training set is solely made of data from oceanic regions and more data from land may need to be added. This is further supported by the observed macrophysical properties of the cumuli, including the size, shape, and spatial (horizontal and vertical) distributions based on the CAMP2Ex ASTER data that are also summarized in this thesis. Results showed similarities to previous studies using ASTER data in other oceanic regions, which may explain the need in the training set for data from land where cloud properties may be different. The relationship of the observed macrophysical properties and the large-scale meteorological conditions is also investigated in this thesis. Results show that total column water vapor, lower‐tropospheric stability, and estimated inversion strength are the variables that contribute the most to the variation in mean cloud top height, while wind speed near the surface and relative humidity near the cloud contribute most to the variation in cloud fraction.

Name thesis:degree_name

M.S.

Level thesis:degree_level

Thesis

Discipline thesis:degree_discipline

Atmospheric Sciences

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2023

Author dc:creator

• De Vera, Michie Vianca Dichaves

Contributors dc:contributor

• Di Girolamo, Larry

• Cloud Macrophysical Properties
• Cumulus
• Satellite Remote Sensing
• Camp2ex
• Tropical Western Pacific
• Philippines
• Terra
• Aster
• Cloud Mask
• Misr
• Resolution Correction

Statement dc:rights

• Copyright 2023 Michie Vianca De Vera

Language dc:language

en, eng

Handle dc:identifier

https://hdl.handle.net/2142/121266

OAI record oai:identifier

https://www.ideals.illinois.edu/oai-pmh?verb=GetRecord&metadataPrefix=etdms&identifier=oai%3Awww.ideals.illinois.edu%3A2142%2F121266