The jet stream is moving north with global warming, the weather is changing in America, Europe.
- A polar jet stream is a group of winds that separates cold Arctic air from warm air to the south.
- A new study shows that as the Earth warms, the band is moving north and out of position.
- This could lead to more droughts and heat waves in southern Europe and eastern America.
The polar jet stream orbits the northern hemisphere, orbiting up to nine miles from our heads, like a curved, ethereal crown on a planet.
This band of high winds separates cold air from Arctic to hot air to the south, and is responsible for weather transport from west to east across the United States, the Atlantic Ocean, and Europe. It controls how wet and hot these areas are.
But according to a recent study, the jet stream is moving north as global temperatures rise. This is because the delicate balance of hot and cold air that holds the river in place is disturbed. If greenhouse gas emissions continue uninterrupted, the study found, the jet stream will exceed its normal range by 2060.
“The ‘beginning’ of migration north of the jet stream has already begun,” Matthew Usman, a researcher at the University of Arizona’s Climate Systems Center, told Insider.
It will wreak havoc on the northern hemisphere, bringing more extreme events such as droughts and heat waves in southern Europe and eastern America. More rains and floods are expected in northern Europe and Scandinavia, Usman said.
A migrating jet stream.
The North Atlantic Ocean jet stream exists and is in place, causing a collision between hot air between hot air and cold air in the Arctic. Once these aerial masses are found, they move eastward at a speed of 110 miles per hour, which moves in a rotation of the earth.
But rising air temperatures disrupt this movement and flow. The Arctic is warming twice as fast as the rest of the planet. So that the hot air travels north before the cold air is received, causing the position of the jet stream to migrate to higher altitudes.
Usman noted that the jet stream is attractive. The position of the band is constantly changing due to the temperature difference which causes it to fluctuate. But his study took a long view, examining the location of the river over the last 1,250 years. To reconstruct this past behavior, researchers looked at samples of ice cover from 50 Greenland ice sheet sites dating to the eighth century. The cores reported how much snow had fallen, and when.
Then, using climate models, the team simulated that if greenhouse gas emissions continued at their current rates, the jet stream could move forward over the next four decades. The results show that the current movement of the wind band is in danger of exceeding any previous shift.
It is expected to deviate significantly from normal, with potentially devastating consequences.
“By pushing the jet stream out of the already large natural range, we could expose ourselves to increasingly severe weather hazards in the future,” Usman said.
There could be more droughts and floods.
Osman’s study suggests that the migration of jet streams is likely to heat up the US East Coast faster than ever before. And both North America and Europe will experience more droughts and heat waves.
“At the end of the North Atlantic jet flow, Europe will feel the effects,” Usman said.
In particular, the semi-arid regions of southern Europe may become more barren. Areas of northern Europe that already have wet, mild climates, such as Scandinavia, may become more wet. This extra rain will cause more flooding, as it has engulfed Europe this summer.
Changes in the jet stream can also affect polar vertices.
Some scientists believe that the heat will make the jet stream more wavy than ever.
The path of a jet stream is revolving and sinusoidal because not all warm air travels north at the same rate, nor does all polar air travel uniformly south. So many waves in the wind band.
But a study published last month suggests that melting Arctic sea ice could increase the intensity and size of these deviant bulges. As sea ice melts, more heat and moisture rises from the earth’s surface into space. It acts like a rock thrown into an atmosphere pond – it creates strong waves over the Arctic that disturb the jet stream. This creates whales that push unusually cold air into the equator.
As a result, a higher job pounding, in turn, increases the likelihood of severe winter storms and severe cold in the United States. Examples of this severe winter weather include the Polar Vortex event that hit the United States in 2019 and the winter storm that left millions of taxis without power in February.
“If the jet stream surge increases in the future, it could mean that extreme events, such as polar vortex, could recur,” Usman said.