Case: 18 July 2017

Summary

Closed cell stratocumulus cloud event with aircraft support during the ACE-ENA campaign

Description

This event was one of the better ACE-ENA campaign dates. It featured a traditional summertime marine stratocumulus deck with signatures of drizzle observed by ARM profiling measurements. The event included a G-1 mission (flight takeoff at 8:30 UTC) that encountered an unbroken deck of stratocumulus clouds throughout its entire flight window. Winds were northerly to northwesterly throughout the event. The cloud deck was low for this event (cloud echo top height estimates at approximately 1.0 km AGL), but it was continuous and covered much of the Azores region until 12-13 UTC. After that point, it showed signs of erosion across the region. This event was well-forecasted during this campaign, with this erosion attributed to a thin saturated layer. Inversion height at approximately 1.0 km AGL.

Available assets

Standard ARM profiling assets, SEVIRI. ACE-ENA campaign day, which includes 4 radiosonde launches. RLPROF-FEX. SACR, ARM AAF Gulfstream-1 (G-1)

Critical period: 06:00-12:00

Continuous and closed stratocumulus across the region

Figure 11 True color afternoon MODIS AQUA image with overlaid LES domains. The image domain corresponds to the size of the model forcing domain.