(Michael H. Wong et al. / Geophysical Research Letters, 2021)
Hubble Space Telescope observations over 11 years have helped scientists determine that the average wind speed in the famous Great Red Spot vortex on Jupiter gradually increases
This occurs as the size of the hurricane decreases and its shape is rounded. For 11 years, it has increased by 4%-8%.
The Great Red Spot is a huge anticyclone in the South Tropical Zone (STrZ) of Jupiter's atmosphere
This has been observed for over 350 years and has been studied by many ground-based and space telescopes, as well as interplanetary missions.
The size and durability of the hurricane makes it unique among the vortices of the solar system.
It’s also interesting as a representative of the class of vortex pancakes, which include dark spots on Neptune and some vortices in the Earth's oceans.
Earlier long-term studies have already helped to reveal a decrease in the vortex, a change in its shape from an oval to a circle and a change in color.
Now, a group of planetary scientists led by Michael Wong of the University of California published the results of measuring the speed and direction of winds in the Great Red Spot
They analyzed data from observations of the Hubble Space Telescope from 2009 to 2020.
It turned out that during this period the average wind speed within the Spot increased by 4%–8% (by 0.38–0.69 meters per second in one year).
At the same time, the structure of the winds was influenced by the South Equatorial Belt Outbreak (SEBO) - a powerful convective event accompanied by the transfer of matter and heat from the deep layers of the atmosphere upwards and which took place in 2016-2017.
On the other hand, no effect on the vortex of the South Tropical Disturbance (STrD) in 2017–2018 was observed.
Source:
- Geophysical Research Letters: https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2021GL093982