What is a "big storm" on Mars?

Mars has a bad temper, and sometimes there will be disastrous "big storms". What is the face of this "big storm"? Some time before storm warning, there will be some yellow clouds in the sky of Mars, and these clouds will gather slowly. In a few days, the clouds will grow and storms will brew. A few weeks later, Huang Yun filled the southern hemisphere of Mars, and then covered the whole of Mars. In fact, this Huang Yun is mixed with many dust particles, so the "big storm" is exactly a big sandstorm. This unique Mars phenomenon can be observed through telescopes on Earth. Scientists have put forward some ideas about the formation of this strange "storm". Sandstorms usually start from the summer solstice in the southern hemisphere of Mars, when Mars is at perihelion, so the temperature is very high, which strengthens the air movement there, so the dry atmosphere begins to fly around with dust. When the temperature of dust particles in the wind keeps rising due to the sun's irradiation, it accelerates its rising speed. At this time, the dust in the wind rolled up and formed a big storm. If the wind on the ground meets, the storm will be more violent, and its power can spread from the southern hemisphere to the northern hemisphere, so a global storm will occur. Mars storms occur frequently, and almost every year a storm sweeps across Mars for several months in late spring and early summer.