Shallow marine clouds at the Eastern North Atlantic (ENA) atmospheric observatory are the foci of the third Large-Eddy Simulation (LES) ARM Symbiotic Simulation and Observation (LASSO) scenario, LASSO-ENA. LASSO-ENA simulations are designed around investigating science questions related to cloud organization and precipitation processes.
The simulation prototyping and production are ongoing with specific details to follow. Current thinking is to produce an ensemble of simulations for several dozen days using traditional marine LES domains, which are periodic with 100-meter grid spacing and a modest domain size. The ensembles would blend variations to input data (various reanalysis data sets) and background aerosol assumptions. This would provide information regarding sensitivity to the background meteorology and aerosol conditions for cloud formation.
Case dates are selected to emphasize fetch from the northerly quadrant to minimize island impacts from Graciosa Island in the Azores, where ENA instruments are located. Dates will also span cloud regimes with open, closed, and transitional cloud organization represented.
The basic ensembles will be sampled for producing a series of more detailed simulations using larger domains, possibly higher resolution, and more detailed cloud treatments. Highly detailed cloud treatments using spectral-bin microphysics are also being investigated, with more limited domain sizes.
