Title: Data associated with "Assessing Rain Drop Breakup Parameterizations using Disdrometer Observations"

Abstract: An intercomparison of rain drop mean diameter frequency distribution (RDFD) is performed for numerical simulations of precipitating cloud systems using an array of models and microphysics schemes. This includes results from the Regional Atmospheric Modeling System (RAMS) double-moment microphysics, the Hebrew University Cloud Model bin microphysics (HUCM) interfaced to the RAMS parent model, and the Weather Research and Forecasting Model (WRF) with the Thompson, Morrison, Double Moment 6-Class (WDM6), and National Severe Storm Laboratory (NSSL) double-moment schemes. Simulations are examined with respect to the rain drop size distribution (DSD) volume-number mean diameter (Dm) and intercept parameter (Nw). When compared to a suite of disdrometer observations, the RDFD resulting from each microphysics scheme exhibits varying degrees of mean drop size constraints and peaks in the frequency distribution of Dm. A more detailed investigation of the peaked RDFD from the RAMS simulations suggests that the parameterization of rain drop collisional breakup can impose strong limitations on the evolution of simulated drop growth. As such, a summary and comparison of the drop breakup parameterizations among the forementioned microphysics schemes is presented. While some drop breakup parameterizations are adjusted toward the observations by modifying the threshold diameter for the onset of breakup, this study explores the use of a modified maximum breakup efficiency. This method permits the parameterization to retain its threshold breakup diameter, while limiting the strength of drop breakup and permitting a broader range of drop sizes. As a result, the simulated mean drop sizes are in better agreement with observations.

Contact: Stephen Saleeby, stephen.saleeby@colostate.edu

License information: The material is open access and distributed under the terms and conditions of the Creative Commons Public Domain "No rights reserved" (https://creativecommons.org/share-your-work/public-domain/cc0/).

Recommended data citation: Saleeby, S., Dolan, B., & Bukowski, J. (2022). Data associated with "Assessing Rain Drop Breakup Parameterizations using Disdrometer Observations". Colorado State University. Libraries. http://dx.doi.org/10.25675/10217/235397

Associated article citation: Saleeby, S. M., Dolan, B., Bukowski, J., Van Valkenburg, K., van den Heever, S. C., and Rutledge, S. A. 2022 accepted, In press: Assessing Rain Drop Breakup Parameterizations using Disdrometer Observations. J. Atmos. Sci., https://doi.org/10.1175/JAS-D-21-0335.1

File descriptions:

Note.2017-doe.micro-all.txt - file that describes all of the RAMS archived simulations
included in this study that compares a global database of disdrometer observations and
comparable set RAMS simulations over various parts of the world. 

Python-Notebooks.tar - a series of Python Jupyter Notebooks used to process the
disdrometer and model data for the rain drop LogNw-D0 analysis for the manuscript.
These scripts can be used to replot the data as needed.

logNw-D0_data.tar.gz - compressed tarball file containing all of the LogNw-D0 data
files and plots used in the manuscript. These were created using the Python Notebook
scripts provided in the repository.

x.DisdrometerData.tar - tarball file of the "world" or global disdrometer observations
of rain drop LogNw and D0 as well as the convective cases IFloods, SGP, and MC3E. These
data can be accessed and plotted with the provided Jupyter notebooks.

RAMSINs.tar - while the actual RAMS model data cannot be uploaded since it consumes many
terabytes of space, the RAMS namelist files or RAMSIN files are included here for all of
the case studies. The model data can be reproduced with these control files.

WRF-namelist-files.tar - the WRF model output data is also too large to backup. However
the namelists for each simulation are provided here for WRF version 3.9.1.


Detailed RAMS documentation and user guides are avaible at: https://vandenheever.atmos.colostate.edu/vdhpage/rams.php.