The Alpha 1 release is the first dissemination of simulations and analysis tools from the Large-Eddy Simulation (LES) ARM Symbiotic Simulation and Observation (LASSO) project for five shallow convection cases.

Alpha 1 Overview

This release is in the form of an ARM evaluation product, and this web page serves as a high-level interface to the data bundles and Bundle Browser. The collection of data files, which entails a collection of so called “data bundles,” consists of:

  • LES input and outputs
  • ARM observations co-registered on the model grid
  • Model diagnostics and skill scores, and
  • Quicklooks of various fields.

The data bundles are available at the evaluation product location within ARM’s Data Archive. In addition, a web-based interface is provided, called the LASSO Bundle Browser, for users to find simulations of interest through examination of the LES performance relative to select ARM observations.

This release contains 192 simulations and the corresponding model-observation comparisons for different LES models, large-scale forcings, model configurations, and preliminary observational products that the LASSO team is using to assess workflow options for use in operations.

Simulations from both the System for Atmospheric Modeling (SAM) and the Weather Research and Forecasting (WRF) model are available that have been driven using a range of forcings under consideration for use with LASSO. Many of the simulations are directly comparable, e.g., they use the same model configuration and only differ in the forcing or initial conditions used to drive the model. Other simulations differ in the particular choice of microphysics. The release also serves as an initial introduction to the skill scores being designed for model evaluation. More complete details are available in the release documentation.

LASSO Bundle Browser

Preliminary effort has gone into designing the Bundle Browser interface to help users find simulations of relevance for their needs. The browser is a tool based on the Cassandra NoSQL database methodology that permits search by value queries of the skill scores and dynamically creates quicklook plots of selected simulations for selected metrics. See the LASSO Alpha 1 Description for details on the browser.

Using Alpha 1

Note that the simulations within this release represent the typical behavior to be expected from LES using best-practice configurations and are valid for use in various research applications. However, as made evident by the comparisons to observations, there is a range of model behavior. We recommend that users contact the LASSO team to ensure the details of the simulations are understood and that the simulations are used appropriately for the given application.

Looking for Feedback

An objective for the Alpha 1 release is to solicit feedback from the community. Efforts to improve the model configuration, forcings, and analysis tools are ongoing and will evolve based on user feedback and continued effort. We encourage users to explore the available simulations and tools and to share their experience and ideas for improvement with the LASSO team William Gustafson, Lead Principal Investigator or Andrew Vogelmann, Co-Principal Investigator.