Morphological analysis of Jupiter’s small-scale pop-up clouds

The Juno mission, in orbit around Jupiter since July 2016, has provided an unprecedented view of the planet’s atmospheric dynamics. High-resolution images from the JunoCam camera aboard Juno have led to the identification of small-scale compact cloud formations known as pop-up clouds [1], which appear as elevated features projecting shadows over their surrounding clouds. These features are distinguished from large-scale strong convective outbreaks by their smaller spatial and vertical scales [2, 3], suggesting they are powered by the less vigorous ammonia moist convection [4]. A compact cluster of clouds of this type was also observed within the Great Red Spot in the very high-resolution images from JunoCam [5]. While deep convective phenomena can have large vertical extents reaching altitudes of a few tens of kilometers above the main cloud deck [6], recent studies suggest that pop-up clouds rise to around 15 km above their immediate surroundings [4].

In this work, we used JunoCam high-resolution images to conduct a morphological classification of these small-scale moist convection pop-up clouds across a wide range of latitudes and dynamical environments, including Folded Filamentary Regions (FFRs), vortex interiors, vortex peripheries, and others. In addition, we performed a comprehensive morphological characterization of these features, employing a Geographic Information System (GIS) framework [7] with a geodetic metric, based on an oblate spheroid model defined by Jupiter’s radius and flattening parameter. Our results show that pop-up clouds are present across all latitudes covered by JunoCam and exhibit significant spatial clustering. The morphological classification highlights a variety of shapes, from compact cells and cloud-clusterings to elongated filaments. Measurements reveal varying horizontal scales but consistent separations within individual clusters. Furthermore, we also studied vertical elevations derived from projected shadows, which remained below 15 km above the surrounding cloud deck.

 

References

[1] Hansen et al. (2019). JunoCam Images of Castellanus Clouds on Jupiter. AGU Fall Meeting Abstracts, 2019, P44A-05. https://ui.adsabs.harvard.edu/abs/2019AGUFM.P44A..05H

 

[2] Orton et al. (2022). Investigating Relative Cloud Heights in Jupiter Using Juno's JunoCam Imager. AAS/Division for Planetary Sciences Meeting Abstracts #54, 54, 306.06. https://ui.adsabs.harvard.edu/abs/2022DPS....5430606O

 

[3] Guillot et al. (2024). How high are Jupiter's clouds? From high-resolution JunoCam images to a multi-wavelength analysis. EGU24. doi:10.5194/egusphere-egu24-17351

 

[4] Palotai et al. (2023). Moist convection in the giant planet atmospheres. Remote Sensing, 15, 219. doi:10.3390/rs15010219

 

[5] Sánchez-Lavega A. et al. (2018), The rich dynamics of Jupiter’s Great Red Spot from JunoCam – Juno images, Astronomical J., 156, 162 (9pp), doi:10.3847/1538-3881/aada81

 

[6] Sánchez-Lavega et al. (2008). Depth of a strong jovian jet from a planetary-scale disturbance driven by storms. Nature, 451 (7177), 437–440. doi:10.1038/nature06533

 

[7] Trent M. Hare, Angelo P. Rossi, Alessandro Frigeri, Chiara Marmo. Interoperability in planetary research for geospatial data analysis, Planetary and Space Science, Volume 150, 2018, ISSN 0032-0633, https://doi.org/10.1016/j.pss.2017.04.004