Something strange is going on with temperatures on Jupiter, according to 40 years of research

The study reveals a mysterious link between apparently linked temperature variations in regions thousands of miles apart. Anyone have any ideas?

For no less than four decades, researchers have studied temperatures in the upper layer of Jupiter’s atmosphere, the so-called troposphere. This is the layer of air in which ‘weather’ takes place and where the characteristic colored striped cloud bands appear. After 40 years, the team makes a curious discovery. For example, they found very unexpected patterns in how the temperatures of these cloud bands change over time.

Troposphere
Jupiter’s troposphere has much in common with Earth’s. Clouds and thunderstorms also form in Jupiter’s troposphere. To understand the local weather on the gas giant, scientists study certain properties, such as wind, pressure, humidity and, of course, temperature. We know a bit more about previous missions, including the Pioneer 10 and 11 unmanned spacecraft that visited Jupiter in the 1970s. For example, it is known that lower temperatures can generally be associated with brighter areas and whiter, while the darker, brownish-red bands are warmer.

These infrared images of Jupiter were obtained in 2016 using ESA’s Very Large Telescope. The colors represent temperatures and clouds: blue-colored areas are cold and cloudy, while orange-colored areas are warmer and cloudless. Image: ESO/LN Fletcher

Until now, however, it was still unclear how temperatures in Jupiter’s troposphere vary over the long term. But 40 years of groundbreaking new research now greatly expands our knowledge about it. In the study published in natural astronomy, the team looked at the bright infrared glow coming from the hottest regions of the atmosphere, then measured the temperature above Jupiter’s colorful cloud cover. The researchers collected this data at regular intervals, each for 12 Earth years.

rounds
One of the main conclusions of this study is that temperatures on Jupiter seem to rise and fall periodically. It is like a cycle, although it cannot be linked to seasons or other cycles known to scientists. Unlike Earth, where distinct seasons occur due to its 23.5 degree tilt, Jupiter has no seasons, as its axis is tilted only about 3 degrees. For this reason, the researchers did not expect temperatures on Jupiter to vary regularly.

Temperature variations
But even more surprising is the discovery of a mysterious temperature relationship between regions thousands of miles apart. “It’s the weirdest of them all,” says researcher Glenn Orton. “We found a correlation between how temperatures vary at very distant latitudes.” While temperatures rose at specific latitudes in the northern hemisphere, temperatures fell at the same latitudes in the southern hemisphere. “It’s similar to an earthly phenomenon,” Orton continues. “Weather and climate patterns in one region can also have a noticeable impact on Earth on the weather elsewhere.”

Cause
The next challenge is to find out what exactly causes the cyclical and seemingly synchronized changes discovered on Jupiter. At the moment, researchers are still in the dark, although they have a low suspicion. For example, they discovered that the temperature higher up in the stratosphere periodically rises and falls in a pattern exactly opposite to that of the troposphere. This suggests that changes in the stratosphere lead to changes in the troposphere and vice versa. However, more research is needed to fully understand this. “We have now solved part of the puzzle, which is that the atmosphere has natural cycles,” said researcher Leigh Fletcher. “To understand what drives these patterns and why they occur on specific time scales, we need to look both above and below cloud layers.”

The study is an important step towards a better understanding of what determines the weather on the largest planet in our solar system. Eventually, the researchers even hope to be able to predict the local weather on Jupiter. “Measuring long-term temperature changes and cycles is critical for this,” says Fletcher. “We now hope to uncover cause and effect in Jupiter’s atmosphere. We may be able to apply what we learn next about Jupiter to other giant planets to see if similar patterns appear there.