People

Professor Jasper F. Kok (CV) – Ph.D. (Applied Physics, University of Michigan, 2009)

Jasper Kok was born in the Netherlands, where he obtained a B.S. in physics at Leiden University. He then moved to the United States for graduate school, and obtained his PhD in Applied Physics from the University of Michigan in 2009, for which he received a Distinguished Dissertation Award. He then took an Advanced Study Program postdoctoral fellowship at the National Center for Atmospheric Research, followed by an NSF Climate and Large-Scale Dynamics postdoctoral fellowship at Cornell University. Jasper joined the faculty at the department of Atmospheric and Oceanic Sciences at UCLA in 2013, was awarded an NSF CAREER grant in 2016, received tenure in 2017, received the American Meteorological Society’s Henry Houghton Early Career award in 2020, and was promoted to Full Professor in 2021.

Contact info:
Office: 7142 Math Sciences Building, UCLA
Email: jfkok@ucla.edu
Phone: Email is the best way to get a hold of me.

If you are a prospective student or postdoc and are interested in joining my group, feel free to contact me. I am passionate about broadening participation for students and researchers from groups that are underrepresented in the geosciences. I thus particularly welcome interest from female applicants and underrepresented minorities.

Project scientist Ashok Gupta (ashokgupta@atmos.ucla.edu)

Dr. Gupta’s research focuses on aerosol and cloud physics, specifically quantifying the influence of ice nucleating particles (INP) from dust on mixed-phase and cirrus clouds. He is also quantifying the impact of volcanic eruptions on Earth’s climate. To investigate these questions, Dr. Gupta utilizes in situ data from the ARM program, satellite data, radiative transfer modeling, 3D WRF, and Aerosol-Cloud models. Dr. Gupta’s current research is centered around three main areas:

(a) Quantifying changes in microphysical properties, such as ice concentrations and hydrometeors, macrophysical properties like cloud fraction and precipitation patterns, and radiative properties of high-latitude mixed-phase clouds (as well as tropical cirrus clouds) due to changes in aerosol (such as dust aerosol) and meteorological conditions since pre-industrial times.

(b) Retrieving the vertical distribution of dust aerosol using a suite of spaceborne instruments, including SAGE-III, CATS, CALIPSO, and MODIS.

(c) Quantifying the impact of submarine eruptions, such as the Hunga eruption, on Earth’s climate by evaluating the perturbations caused by water vapor, sulfate aerosols, and ozone.

Graduate student Olivia Salaben (osalaben@g.ucla.edu) – B.A (UC Berkeley)

Olivia studies regional dust direct radiative effect and forcing, particularly using regional observational constraints to quantify dust-radiation interactions. Currently, she is working on constraining the direct radiative effect and forcing of North African dust. Her research interests include regional dust and anthropogenic dust. Olivia is very passionate about environmental justice and leads on the board of the Climate Justice Collective at UCLA and with UC Green New Deal Coalition.

Graduate student Vanessa Maciel (fvmaciel@ucla.edu) – B.S. (UC Santa Cruz), M.S. (San Jose State University)

The presence of an ice nucleating particle (INP) can alter the ice crystal size distribution of a cirrus or mixed-phase cloud which controls how it interacts with incoming and outgoing radiation. Vanessa is currently using observational data to investigate the impacts that dust, an efficient INP, has on the microphysical structure of these clouds. It is important to fully understand this, especially in the context of climate change, as it is a major contribution to the uncertainty in global climate models. Therefore, she aims to build a climatology for dust in the cirrus and mixed-phase cloud regime for use in a model to help improve it. Vanessa is also serving as the Social Media Chair for Chi Epsilon Pi (XEP), the AOS department’s graduate student organization. In the future, she hopes to continue in academia in a faculty position where she can work on similar research and advise students from diverse backgrounds while creating an inclusive environment. In her free time, Vanessa enjoys drawing, afternoon tea, watching horror movies and cuddling with her cat.

Recent group alumni

Some happy research group members at 2019 graduation. From left-to-right: former undergraduate researchers Yang (Kitty) Wang, Kaylie Cohanim, Chloe Whicker, and Kenyon Chow.

Former PhD student Danny Min Leung (dannymleung@ucla.edu) – PhD (UCLA, 2023)

For his PhD, Danny developed a detailed and more accurate parameterizations of the effects of boundary-layer turbulence, surface roughness, and other physical mechanisms on dust aerosol emissions. He incorporated this parameterization schemes into the default version of the Community Earth System Model (CESM), facilitated by an Advanced Study Program (ASP) graduate visitor fellowship. He is now an ASP postdoctoral fellow.

Former graduate student Yue Huang (hyue3@yahoo.com, website) – PhD (UCLA, 2021)

For her PhD, Yue worked on “Observational constraints on dust size and shape.” She did impactful work quantifying dust fluxes from sand dunes (here), quantifying the globally-representative asphericity of desert dust (here), and figuring out how to convert between different types of measurements of dust particle sizes so that comparisons between models and measurements are closer to comparing apples to apples (here). She is now a postdoctoral fellow with Ron Miller at Columbia University, for which she received a prestigious Earth Institute postdoctoral fellowship.

Former postdoctoral fellow Adeyemi Adebiyi (aaadebiyi@ucmerced.edu, website) – Ph.D. (University of Miami, 2016)

Yemi was a University of California President’s Postdoctoral Fellow whose work has shown that that the atmosphere contains an astonishing 17 million tons of coarse dust (particles with diameter > 5 um), which accounts about a third of the atmosphere’s total particulate matter load. Climate models account for only about a quarter of this coarse dust, thereby missing important effects on climate and weather. For this impactful work, Yemi received a prestigious Chancellor’s Award for Postdoctoral Research. Yemi is now an assistant professor at the University of California – Merced. Member of group from 2017 – 2021.

Less recent group alumni

Former postdoctoral scholar Jun Meng (jun.meng@ucla.edu). Developed a new parameterization for the size distribution of emitted dust aerosols that accounts for super coarse dust. Now an assistant professor at Washington State University. Member of group from 2020 – 2022.

Former undergraduate researcher Robin Anthony-Petersen used satellite data to investigate impacts of dust on clouds in the tropical North Atlantic. Robin is currently a graduate student at the University of California – Berkeley. Member of group from 2019 – 2021.

Former undergraduate researcher Alana Dodero used satellite data during the 2020 massive “Godzilla” dust storm to investigate the impact of the asphericity of dust on its optical properties. Member of group in 2020. Now a graduate student at TAMU.

Former postdoctoral fellow Francesco Comola developed an insightful parameterization for climate models of the effects of turbulence on fluxes of sand and dust (here). Member of group from 2016 – 2019.

Former undergraduate researcher Chloe Whicker studied the surface concentration of desert dust, which has implications for understanding human health impacts. Chloe is currently a postdoctoral scholar at the University of California – Irvine, after graduating from the University of Michigan. Member of group from 2018 – 2019.

Former undergraduate researcher Kaylie Cohanim researched wind-blown sand transport on Earth and other planetary bodies (mainly Titan), and its implications on climate and the development of geological surfaces. Now a graduate student at UCLA. Member of group in 2018.

Former postdoctoral fellow Raleigh Martin performed extensive field measurements of wind-blown sand using novel methodology, resulting in a number of excellent publications. Member of group from 2013 – 2017. Now a Program Director in the Division of Earth Sciences at the National Science Foundation.