Mystery of the Great Lakes Smoke

  In southern Africa, there is a large lake with an area of ​​nearly 30,000 square kilometers. The lake is vast and beautiful, but it is incredible that sometimes hundreds of meters high gyro-shaped plumes of smoke appear on the lake. The smoke curls up straight up to the blue clouds. Mysterious and weird.
  A meeting of the Great Lakes smoke
   this would smoke in the Great Lakes called Lake Malawi, in southern Africa, Malawi, Mozambique and Tanzania at the junction of the three countries, the locals call it the Lake Nyasa, which means “big Water or lake”. The scenery of Lake Malawi can be described as picturesque. The water here is clear and clean. On a windless day in September, the transparency of the lake can reach 20 meters. Standing on a boat or by the lake, you can see a school of fish swimming around; it is also a great place for diving. Even if you don’t use any equipment, you can see the bottom of the lake at a glance. The lake is clear and beautiful, and the surrounding scenery is not inferior. The big lake is surrounded by mountains on three sides, surrounded by peaks and mountains, surrounded by high cliffs, waterfalls flying, gurgling water, complementing the lake water, and it is known as the most magnificent lake and mountains in Central and South Africa.
   However, this big lake sometimes has mysterious smoking phenomenon, which is very surprising: at a certain dawn in the rainy season, suddenly, the lake surface in the distance rises up with gray-black smoke clouds, which extend upward in a spiral shape. , Some spread their teeth and dance claws, spreading everywhere; some light and wandering like threads of silk; some were as dark as ink, murderous…In a blink of an eye, the smoke rose hundreds of meters high, like a sharp sword thrusting into the clear sky, It almost meets the white clouds in the sky, and looks shocking.
   Great Lakes smoke guess
   , hey, why suddenly the Great Lakes smoke it?
   Conjecture 1: The lake god is angry. Local indigenous people believe that there is a lake god living in Lake Malawi who is in charge of the large and small fish and shrimps in the entire lake. Most of the time, this god has nothing to do and has to lie on the bottom of the lake to sleep. Taking advantage of this opportunity, people hurried to fish and catch shrimp on the lake. But one day each year, the lake god would suddenly wake up. When he saw his aquatic people were wildly captured by humans, he couldn’t help being furious. The anger rushed out of the water and immediately formed a cloud of smoke that hit the sky.
   Conjecture 2: Volcano eruption. Volcanic eruption is the strongest manifestation of the earth’s internal heat energy on the surface. During this process, volcanoes will not only emit fiery red magma, but also emit a large amount of smoke and ash. Volcanic eruptions not only occur on land, but also occur at the bottom of the ocean thousands of meters deep, and many islands are the products of volcanic eruptions. According to scientific investigations, the area where Lake Malawi is located is located in the Great Rift Valley of Africa. Under the joint action of the African plate and the Indian Ocean plate, the geology of this area is very unstable, and volcanic eruptions are entirely possible.
   So, are the smoke clouds on the Great Lakes really formed by volcanic eruptions? No! Because the volcanic smoke cloud is generally mushroom-shaped and the color is thicker, more importantly, after each smoke, no trace of volcanic eruption is found in the lake.
   Conjecture 3: Gas burning. This statement is not a fantasy, nor is it groundless, because some lakes have flammable gases such as methane dissolved in them. For example, only a few hundred kilometers away from Lake Malawi, there is a Kivu. lake. Its area is much smaller than that of Lake Malawi, but according to scientific determination, about 55 billion cubic meters of methane and other gases are dissolved in the lake water up to 300 meters deep. In other words, Lake Kivu is like a giant filled with fuel. The barrel may burn at any time.
   If there are flammable gases in Lake Malawi, in the case of insufficient combustion, a lot of smoke and clouds may indeed be produced. However, this large lake is completely different from Lake Kivu. Its water quality is clear and transparent, and scientific investigations have not found the lake. There is flammable gas.
   It turned out to be the lake gnats!
   After investigating, the scientists discovered that the culprit of the smoke cloud was the unremarkable little insect-the lake gnat.
   Gnats are what we usually call mosquitoes. There are more than 1270 species of gnats known in the world, and lake gnats are just one of them. They have long, needle-like mouths, large wings, short feet, and a hump-back bulge. Although they look a little scary, they are very “petite”, with a body length of 2-5 mm.
   How can these little guys form huge clouds of hundreds of meters high?
   It turned out that on the bottom of Lake Malawi, there is a dead water area formed by deep-water vortices. This can be said to be a desert area of ​​a large lake. Due to the low oxygen content, many organisms, including fish and shrimps, cannot survive. However, there is The exception is the larvae of lake gnats: hundreds of millions of larvae hatch in the water and grow up carefree and happy. When the rainy season comes, these guys have grown up, so one day at dawn, they collectively surfaced on the water, unfolding a magical transformation show: they degenerated into insects, grew wings, and immediately flew to the sky to find a partner. When hundreds of millions of lake gnats fly off the lake and gather together to mate, they form a gyroscopic cloud of smoke hundreds of meters high. Because of the long distance, people on the shore can’t really see it, so they mistakenly think that the big lake is smoking.
   This spectacle does not last long. After the mating is over, the lake gnats all fall to the surface of the water and die immediately after laying their eggs, but after their eggs hatch in the lake, the larvae will enter the dead water area to live again. When the rainy season comes, these little guys, like their parents, will once again gather in large numbers on the lake surface, staged a shocking spectacle of smoking in the great lake.