CACTI Deep Convection

The Cloud, Aerosol, and Complex Terrain Interactions (CACTI) field campaign is the focus of the second Large-Eddy Simulation (LES) ARM Symbiotic Simulation and Observation (LASSO) scenario, generally referred to as the LASSO-CACTI scenario.

The LASSO-CACTI datastream consists of a library of mesoscale and large-eddy simulations located near Córdoba, Argentina, for selected case dates between October 2018 through March 2019. Twenty days have been simulated with grid spacings down to 2.5 kilometers using an ensemble of 33 different forcing data sets. This is further refined for nine of the days using nested LES simulations down to 100-meter grid spacing.

All mesoscale and LES simulations are assessed through comparisons with regionally representative observations within the vicinity of the ARM Mobile Facility using skill scores. The skill scores characterize the level of agreement of convective area development, through comparison with satellite brightness temperatures; local convective intensity, through comparison with radar echo-top heights; and surface rainfall, determined from radar data. These scores are presented in plots and available to download in CSV files. In addition, plots are available that compare simulated and observed soundings.

The CACTI field campaign occurred from October 2018 through April 2019 in the Sierras de Córdoba mountain range of north-central Argentina. ARM deployed a suite of instruments that included surface meteorology stations, scanning radars, radiosonde launchers, scanning lidars, and other instrumentation. In addition, the ARM Aerial Facility Gulfstream-159 (G-1) aircraft flew on selected days.

CACTI was also concurrent with the National Science Foundation’s Remote Sensing of Electrification, Lightning, and Mesoscale/Microscale Processes with Adaptive Ground Observations (RELAMPAGO) field campaign, which brought with it an additional suite of instruments that synergistically enhanced ARM’s measurements.

A beta release of the LASSO-CACTI datastream was released in May 2022. The beta release has been superseded by the full production release, with files available through the LASSO-CACTI Bundle Browser. The bundle browser contains quicklook images to assist in finding periods of interest and executing data ordering. (Note that using Globus to download the files greatly speeds up the process over scp/ftp and also provides failure protection.)

The large size of the LASSO-CACTI library could be an impediment for many researchers, so ARM also makes available high performance computing (HPC) resources for users to do data analysis, plotting, and related research directly with the LASSO data without having to copy the files from ARM’s computers. Portions of the LASSO-CACTI datastream are currently pre-staged on ARM’s Cumulus HPC cluster, where users can directly interact with the files either via Jupyter Notebooks or HPC nodes.

Direct access to JupyterHub and the computational nodes can be made available upon request. Contact lasso@arm.gov for more information about using ARM’s computing resources to work with LASSO-CACTI data.

More information on LASSO-CACTI can be obtained from the LASSO-CACTI Technical Document or by emailing LASSO Principal Investigator William Gustafson at lasso@arm.gov.

Announcements about LASSO-CACTI will also be sent to the LASSO email list and in the LASSO-CACTI discussion forum.