Annareli Morales, Ph.D. Candidate ☀

2014-Present - Ph.D. dissertation, "Exploring the Microphysical and Environmental Controls on Orographic Precipitation", University of Michigan

My PhD dissertation involves understanding which environmental and microphysical parameters control where and how much precipitation falls when an atmospheric river interacts with terrain. An atmospheric river (AR) is a long filament of very moist air extending from the tropics to the extr-tropics. When ARs interact with the West Coast mountains of the US, heavy precipitation occurs on the windward side of the mountain. This results in flash flooding and up to 50% of the fresh water resources, mostly through snowfall. To understand how our forecasts of these AR events are affected by parameter uncertainty in our numerical models, I perform idealized simulations of 2D moist, nearly neutral flow over a bell-shaped mountain and perturb mutliple microphysical parameters. In addition, I test the affect of environmental parameter uncertainty over a typical range of observational uncertainty. I have applied a statistical technique called the Morris Screening Method, which performs multi-parameter perturbations to determine the most influential parameters to precipitation, while being computationally affordable. This method also accounts for possible non-linear parameter perturbations and provides a subset of the most influential parameters to precipitation to be further analyzed using more complex Bayesian methods. The results from my dissertation have a broader impact on hazard prediction, water management, and ensemble forecasting. Please see my latest publications for details.

2013-2014 - M.S. Thesis, "Effect of Latent Heating on Mesoscale Vortex Development during Extreme Precipitation: Colorado, September 2013", Colorado State University

I investigated a mesoscale vortex (mesovortex) that was observed during the heavy precipitation event of September 2013 in Colorado. This mesovortex was observed at the same time as the city of Boulder experienced its heaviest rainfall rates, which resulted in flash flooding. One of the goals of the study was to understand the relationship between the physical processes occurring in the storm, the development of the circulation, and the circulation's effects on the environment. To explore these relationships, I used the Advanced Research WRF (ARW) model to simulate the mesovortex and test the effects of latent heating on its development. My results suggested that the latent heat released from the storm system led to the development of the mesovortex near the surface. Furthermore, the mesovortex had an influence ont the environmental flow, enhancing convection and precipitation. These findings are important because if we want to properly forecast extreme precipitation and the potential for flash flooding, our numerical weather prediction models need to be capable of representing the physical processes within the storm and their impact on the development of such mesovortices, which both result from, and help enhance heavy rain.

Summer 2012 - SOARS Program, "Sensitivity of a Simulated Deep Convective Storm to WRF Microphysical Schemes and Horizontal Resolution", NCAR

I used the Weather Research and Forecasting (WRF) model to simulate an idealized, isolated, single-cell deep convective storm. I compared different microphysical parameterizations at various horizonal grid spacings to understand their impact on the storm's development, intensity, structure, and precipitation efficiency under the guidance of Drs. Hugh Morrison and Cecille Villanueva-Birriel. These results were presented at the 2012 Young Scientist Symposium and the 93rd AMS Annual Meeting.

Fall 2011 - Capstone Undergradute Research Project, "PartMC Model Simulations of Internally Mixed Aerosol Particles", University of Illinois

I used the Particle-resolved Monte Carlo (PartMC) aerosol model to simulate and understand how dust and sea salt particles interact during internal mixing processes under the guidance of Dr. Nicole Reimer and Ph.D. candidate Joseph Ching.

Summer 2011 - SOARS Program, "Semi-Empirical Functions Describing the Response of Short-Lived Radicals to their Driving Forces in the WRF/Chem Model", NCAR

I worked with output from the WRF-Chem model to analyze and correlate the short-lived radical, OH, with its environmental and chemical driving factors under the guidance of Drs. Sasha Madronich and Alma Hodzic. These results were presented at the 2011 SACNAS National Conference and the AMS 11th Student Conference.