8 explanation regarding the emergence of black clouds resembling a tsunami wave in Aceh
The appearance of a black cloud resembling a tsunami wave has excited the residents of Meulaboh, Aceh. Member of the National Institute of Aeronautics and Space Agency (LAPAN) Disaster Reaction and Analysis Team (TREAK), Ina Juaeni, said that the appearance of the Arcus cloud which is rarely seen indicates strong winds will occur, followed by an imminent storm.
Quoted from Antara, Wednesday (12/8), Ina explained on LAPAN's official Twitter account that the clouds that had made a scene did appear in several forms. Sometimes with a beautiful appearance, but partly in a creepy form.
These types of clouds, according to one of the researchers at the LAPAN's Center for Atmospheric Science and Technology, are extremely rare. So that it grows and dies depending on the parent cloud.
Arcus clouds have a horizontal structure that is usually seen along the front alongside Cumulonimbus clouds. Arcus clouds are not associated with the appearance of tornadoes but can bring rain or thunderstorms.
They usually form at an altitude near the surface of up to 1.9 kilometers (km). Arcus shaped long coils horizontally usually separated from parent cloud (Cb), while flat Arcus cloud or long plank horizontally unite with cloud base Cb.
Arcus clouds are formed when cold air from within a storm system descends and spreads out. The cold air, said Ina, inhibits the increase in hot air mass, and when cold air rises together with hot humid air, it condenses.
The clouds are formed due to the changing wind. The outside of the cloud appears smooth while the inside of the cloud looks rough due to the strong wind.
The appearance of the Arcus cloud is a sign that a strong wind will soon appear. Both the scroll-shaped Arcus and the flat Arcus are warnings of a rainstorm.
Arcus clouds are very rare, flat shapes are more common, he said. These clouds are usually found along the coast, but can also form in non-coastal areas.