Haihao phenomenon appears in the sea near Dalian. What kind of phenomenon is this?
The fog rises from the sea, and the islands in the distance are looming. Seagulls shuttle in the fog, just like a fairyland... "Haihao" landscape appears in the waters of Donggang and Fujiazhuang. Experts said that the occurrence of this phenomenon is related to the sharp drop in temperature. "Hai Hao" is called "evaporative fog" in meteorology. It is a weather phenomenon that occurs under special weather conditions. It occurs on the unfrozen water of the sea in cold winter.
In winter, the temperature of sea water is actually higher than that of land. Haihao is essentially an evaporative fog. That is, when dry and cold air passes over the sea surface, the sea water itself is relatively warm, so the intersection of cold and warm causes the water vapor on the surface to evaporate rapidly, and then quickly condenses into fog when it encounters cold.
In recent years, "Hai Hao" wonders have appeared many times in Fujiazhuang, Shicao and other sea areas in our city. Liu Yuling, a senior engineer at the Dalian Ocean Forecasting Station, said that the occurrence of the "Hai Hao" phenomenon requires two conditions: temperature difference and condensation nuclei. The water temperature in the sea area around Dalian is around 10 degrees Celsius, and the air temperature is more than ten degrees below zero. The difference between the two is more than 20 degrees Celsius. The temperature of sea water is higher than that of air, and sea water evaporates into water vapor, which quickly condenses when encountering cold air, so the "sea halo" phenomenon occurs.
The reason is basically the same as the white smoke when we boil water. It is caused by high water temperature and low temperature. The higher the water temperature, the easier it is to evaporate water vapor. Therefore, when boiling water, the hot water temperature is 100℃. The temperature is much higher than the temperature of the air above it, so when water vapor enters the air, it will encounter cold and quickly condense into small droplets. This is how the white mist that appears when boiling water is formed.
This type of phenomenon is very common in winter in the north, and may occur as long as the weather is experiencing extremely rapid cooling. Some time ago, Changbai Mountain Tianchi also appeared, and the lake surface boiled like a boiling pot.
In nature, water vapor also evaporates in oceans, lakes, rivers and other waters, as well as in some woods or moist soil. During the process of rising in the air, it forms small droplets or small ice crystals when it encounters cold. , appears as white mist near the ground, and becomes clouds high in the sky.