Satellite images showed two unusual storms over Europe in March.

In March 2022, several major storms brought Sahara dust clouds to Europe. One of them also brought persistent, dusty cirrus clouds, which covered a large cloud from Iberia to the North Pole for more than a week. This is an unusual storm, which scientists have only recently begun to understand. It is called "dust jet baroclinic storm" (DIBS), which is characterized by icy clouds full of dust.

In mid-March, the atmospheric river containing Sahara dust was entrained by DIBS and rose to the troposphere, reaching a height of 10 km. As nucleation particles of ice, these dust particles lead to the formation of cold and dusty cirrus clouds. They lasted for nearly a week and covered most of Europe and Asia.

Mike Fromm, a meteorologist at the US Naval Research Laboratory, said: "In fact, two DIBs have been formed. The fact that the Dust River supports two independent areas makes this noteworthy, because it is more common to see a single storm caused by dust inflow. "

The first storm started on March 5, 2022, and spread from Poland, Czech Republic and Austria to the eastern Mediterranean. This is also unusual, Fromm said, because "DIBS is usually directly related to its dry dust source, which is closer to the desert itself".

On March 16, the second storm followed the classic model and rotated near the dust source in Africa. This huge and extensive dust cloud continues to move northward over Europe, towards Scandinavia and the Arctic Ocean. Then, it moved eastward in northern Russia, and then made an anticyclonic turn on March 20, turning back to Eastern Europe and the Black Sea.

In the above picture, the cloud top is concave. This image was taken by the Moderate Resolution Imaging Spectrometer (MODIS) on NASA Terra satellite on March 6th, 2022 at 438+7th. "We still don't know why this happened," Fromm said, "but it is unique to Dubs."

Colin Sefto, an atmospheric scientist at NASA's Goddard Space Flight Center, analyzed the storm in mid-March and showed that most of the dust circulated at the top of the clouds. "This means that there is enough dust at the top of the cloud to make the usual white clouds have the color of dust, hence the name" jet "part," Fromm said. "In Dubs, dust and storm clouds are integrated."

March 2022 17

The map above shows the dust movement model on March 17, 2007 based on the fifth edition of Goddard Earth Observation System Model (GEOS-5).

Fromm said that it has been observed that the high dust clouds generated by DIBS travel around the world, and sometimes they are mistaken for volcanic ash, which may affect the flight route. They also have local effects. Fromm added that the dust inhaled often remains after the clouds evaporate. In addition, cirrus clouds with long duration will affect the forecast of temperature and precipitation.

In late March, another large sandstorm began to move northward, flying over the Mediterranean and Europe with dust from the Sahara desert. Sefto said that although the recent storm seems to be as big, it may not last that long. "It is a bit unusual for two large-scale (storms) like this to appear almost one after another, but the weather patterns in spring in North Africa and Europe seem to be more conducive to producing sandstorms that reach Europe than at other times of the year."