Feature relative animations (such as when using feature following zoom in AWIPS) provide an intriguing alternative for viewing features in satellite imagery. Such features may include thunderstorms, boundaries, snow bands, dust, and smoke. Closed cellular convection is yet another feature for which a feature relative animation allows for a clearer picture of relevant processes. From the example on 4 Feb 2020 over the eastern Pacific, the divergence from the center of each cell is obvious, painting a picture of the implied rising air in the center of each cell (higher reflectance areas), and sinking air around the edges (low reflectance).
The same features are highlighted in Figure 2, but over a static region.
A zoomed out view of the region shows the development of the above closed cellular convection (in the middle of the scene) within a broader eastern Pacific Ocean anti-cyclone (Fig 3). Open cellualr covnection is also present in this scene, further to the southeast.
A longer animation (Sunday – Tuesday) shows the full evolution of the features behind the early week US trough and surge of cooler air and within the building eastern Pacific anticyclone (Fig 4).
Bill Line (NESDIS and CIRA), Louie Grasso (CIRA)
Have we got fig 1 and fig 2 reversed ?> AWESOME visual science here, tahnk you
Hi Bill A, The figures are correct. Figure 1 is “feature following”, meaning the domain is always centered over the same cell (moving domain geographically). Figure 2 maintains the domain over a static geographic area. Thanks for the compliment!