User:2020008931 Minji/Climate of South Korea

Climate of South Korea


Part of the East Asian Monsoon region, South Korea has a temperate climate with four distinct seasons. The movement of air masses from the Asian continent exerts a greater influence on South Korea's weather than does air movement from the Pacific Ocean. Winters are usually long, cold, and dry. Also, summers are long, hot, and humid. In particular, there is a rainy season in July. Spring and autumn are pleasant but short in duration. Springs are short, warm, and dry. Also in spring, Asian Dust may occur due to the influence of China. Autumns are short, cool, and dry. In autumn, There are frequent typhoons in South Korea.

Seoul's mean temperature in January is −5 to 1 °C; in July the mean temperature is about 22.5 to 27.3 °C. Because of its southern and seagirt location, Jeju Island has warmer and milder weather than other parts of South Korea. Mean temperatures on Jeju range from 3 to 8 °C in January to 23 to 29 °C in July. The mean temperature in northern Gyeonggi-do and Gangwon-do, close to North Korea, is lower than in Seoul.

The country generally has sufficient rainfall to sustain its agriculture. Rarely does less than 750 mm of rainfall in any given year; for the most part, rainfall is over 1000 mm. Amounts of precipitation, however, can vary from year to year. Serious droughts occur about once every eight years, especially in the rice-producing southwestern part of the country. About two-thirds of the annual precipitation occurs between June and September.

Graphically the seasons can be represented this way:

Rainy Season of South Korea
The rainy season of South Korea refers to a phenomenon in which it rains continuously for several days in summer or rainy season, or the weather, or the rain itself. On average, the rainy season is 30 to 35 days, but it does not continue to rain during this period. In fact, it rains for about 15 to 20 days, and among them, it falls only for about 12 to 16 days due to the stagnant front. However, the rainy season varies greatly from year to year. The rainy season is a representative summer weather in East Asian countries, including the Republic of Korea, and accounts for more than 30% of the precipitation on the Korean Peninsula. For this reason, some call the rainy season the "fifth season." It is usually a form of torrential rain that pours suddenly and then stops. In particular, the recent rainy season is referred to as a "nocturnal rainy season," and it is often in the form of a lull during the day, and local heavy rain pouring down at night. In the case of cloudy days, the upper layer may be heated rather than the ground during the day, and at night, the clouds trap the heat of the lower layer while the upper layer cools, so convection develops. In fact, considering that showers come during the day, nights account for a high percentage of 55%. A distinct congestion front is created between the cold and humid Okhotsk Sea air mass located on the northern Russian coast and the hot and humid North Pacific air mass near the Ogasawara Islands, resulting in a rainy season. However, in the case of the Korean Peninsula, not only the Okhotsk Sea air mass but also the cold and dry Siberian air mass contributes to the rainy season. Another cause of the rainy season is said to be the Bering Sea and the Tibetan Plateau. To be exact, the speed of high pressure formation varies depending on the amount of ice in the Bering Sea and the amount of snow accumulated in the Tibetan Plateau, as the rainy season begins with the speed at which each high pressure in the north and south of the Korean Peninsula moves. For this reason, rainy seasons are regarded as a kind of East Asian seasonal wind climate abroad. The rainy season ends when the North Pacific high pressure expands and the Okhotsk Sea fleet retreats. Since then, as the North Pacific high pressure began to dominate the Korean Peninsula, the heat wave began in earnest and entered the middle of summer. However, during the period from summer to autumn, as the North Pacific high pressure contracts and cold air expands in the north, the stagnant front moves south again and settles near the Korean Peninsula, which is called the "Autumn rainy season" or "second rainy season." The autumn rainy season generally occurs between late August and early September, and although it is usually shorter than the early summer rainy season, it sometimes pours more rain than the summer rainy season.

Due to severe climate change caused by global warming in India, daytime temperatures have risen to 32 degrees Celsius since mid-April and 39 degrees in late April, resulting in a strong heat wave in mid-summer, which also hit Korea in early June this year.

On August 30, 2022, the head of the Korea Meteorological Administration pointed out that it was impossible to predict the recent heavy rain, and that the traditional expression of "rainy season" now seems to have expired.

Yellow Dust of South Korea
Yellow Dust refers to a phenomenon in which when low pressure passes through the desert area of China, a large amount of yellow dust floats in the air or lands on the move due to strong winds and topography, affecting Korea. Yellow Dust occurs in desert areas in China and Mongolia, and the addition of several conditions to the sand particles generated here affects South Korea. Deserts where Yellow dust usually occurs include Taklamakan, Ordos, and Gobi. In South Korea, Yellow Dust usually occurs in spring, especially in April.

Yellow dust has been recorded since ancient times, and the damage was not so severe because it was only a sandstorm in ancient times, but in modern times, the damage is getting worse due to China's rapid industrialization and desertification. In summer or autumn, the roots of rain and plants play a role in holding onto the sand. However, in spring, the dry soil, which had been frozen throughout the winter, melts and breaks down into small pieces, resulting in small sand dust of less than 20 μm in size. When low pressure passes over the generated sand dust, it rises to a high sky of 3,000-5,000m by a strong ascending air current and then travels in westerlies and jets of about 30m per second. Since then, it has descended from Korea and Japan, where wind speed has slowed, and sometimes even moved to the United States (April 1998). It takes about two to three days to get to the Korean Peninsula from the origin. In South Korea, Yellow Dust is observed for 3 to 6 days mainly from March to May every year. In terms of the total number of observations nationwide, Jeolla-do (Gwangju, the region with the largest number of occurrences) has been observed. In terms of the number of days of occurrence, Seoul, Gyeonggi and the west coast are long. In rare cases, it was observed in Seoul in the winter of 1991 (November 30, 1991 to December 3). Early yellow dust occurred on January 25, 1999, and severe yellow dust occurred around 1 p.m. on January 2, 2001.

However, there is also a strange tendency, such as yellow dust in December 2022 in winter.

Typhoons of South Korea
South Korea is less vulnerable to typhoons than Japan, Taiwan, the east coast of China, or the Philippines. From one to three typhoons can be expected per year. Typhoons usually pass over South Korea in late summer, especially in August, and bring torrential rains. Flooding occasionally causes considerable damage, as do landslides, given the country's generally mountainous terrain. Typhoons often occur from midsummer to early autumn, July, August, and September. Most of the typhoons invading the Korean Peninsula are concentrated during this period, and sometimes indirect effects occur in June and October. Even October has a direct impact and lands.In the summer, the water on the surface of the ocean, which received hot heat, evaporates and rises by convection and condenses, and the latent heat released heats up the surrounding water vapor again to the troposphere interface. In the case of typhoons heading to Korea, most of them fall into Japan, or Jeju Island, Gyeongsangnam-do, and Jeollanam-do are often directly damaged. However, In September 1984, record floods caused the deaths of 190 people and left 200,000 homeless. This disaster prompted the North Korean government to make an unprecedented offer of humanitarian aid in the form of rice, medicine, clothes, and building materials. South Korea accepted these items and distributed them to flood victims. As global warming progresses, the power of typhoons is likely to become stronger. In fact, hurricanes that occur in the Atlantic Ocean, where the average water temperature is 1 to 2 degrees higher than in the Pacific Ocean, are causing much more intensive damage than typhoons in the Pacific Ocean. Since 2013, the typhoon season has been delayed due to climate change, reducing summer typhoons and increasing autumn typhoons. The season came in October 2013, 2020, and November 2019. As a result, the number of super typhoons is increasing.