The Sea Warming

<Regional Influence>

1) Increase in the extreme weather

        The sea temperatures rising is directly responsible for the typhoon's larger size and increased intensity. The power of a typhoon is determined by the difference between the sea level and the atmospheric temperature above the typhoon, in other words, the warmer the sea, the higher the possibility of a strong typhoon occurring. Due to global warming, latent heat temperature in the ocean rises, making water vapor evaporation more active, which increases the energy source of typhoons.

        Professor Emmanuel's "heat engine theory" is explaining why stronger typhoons occur when sea temperatures rise. According to the theory, a typhoon is a kind of heat engine moving with a temperature difference between warm seawater and cold air above the atmosphere. In other words, the energy released in the process of condensation becomes the energy source of the typhoon. Therefore, the warmer the sea and the lower the temperature of the upper atmosphere, the stronger the typhoon develops. In fact, as a result of simulating typhoons at water temperatures that increased by 2~4℃ in the future near the Korea, the central atmospheric pressure of the two typhoons decreased by 18hPa and 13hPa, and the wind speed increased by 10m/s and 6m/s, respectively. These findings show that as water temperatures rise, stronger typhoons can affect areas with higher latitudes than before.

 

 

 

 

​

​

2) Moisture imbalance

        In Korea, the precipitation for six months counted to June 2022 is 166.8mm, half of the average rainfall of 344.6mm. Climate scientists claimed that the La Niña phenomenon as the reason for the sudden drop in precipitation. In other words, changes in sea temperature affect the increase in drought.

        La Niña is a phenomenon in which the sea level temperature is 0.5 degrees lower than usual for more than five months. According to the Korea Meteorological Administration, in May 2022, sea level temperatures in the El Niño/La Niña monitoring zone in the tropical Pacific were 1.2℃ lower than usual. It occurs when the equatorial trade winds from the east to the west become stronger, and finally warm seawater in the eastern Pacific moves to the western Pacific, making strong high pressure appears in the western Pacific.

​

​

​

​

​

​

​

​

        Analysts said that if sea temperatures rise, then the flow of ocean currents will change and the La Niña phenomenon will increase. In February 2021, researchers at Washington State University released a study showing that drought will increase 10 times in the 21st century compared to the 20th century as a result of the La Niña phenomenon. According to the study, droughts are expected to occur simultaneously in North America, Central America, East Asia, and South Asia, and South Asia.

​

3) Rising sea level

        According to the IPCC 6th Evaluation Report, the average sea level of the Earth increased by 0.20m between 1901 and 2018. Rising sea levels will cause flooding in coastal lowlands, which will permanently flood land. If we do not cope with climate change, the Earth's sea level could rise by more than 0.6m to 1m between 2019 and 2100. After about 100 years, it is expected that permanent flooding damage will occur in coastal cities due to rising sea levels.

        Korea is suffering more damage than in the past due to rising sea levels caused by abnormal weather. In Korea, 27.4% of the total population lives in coastal cities, and coastal cities account for 68% of the total damage in Korea. In order to reduce the damage caused by sea level rise in coastal cities in Korea, a model is used to evaluate the risk of disasters caused by sea level rise. In addition to the use of the model, there is a method of relocating industrial facilities at the pier and installing barriers in low-lying areas where flooding damage is expected to occur to reduce flooding caused by rising sea levels.

        Wido, Buan-gun, Jeollabuk-do, is an island where flooding damage has increased sharply due to climate change. There have been three cases of water being filled up to the body, and countless times have been submerged up to the ankles. In the low-lying Pajeonggeum Village, 220mm of rain fell throughout the day during the summer rainy season in 2020, causing water to fill the entire village to the chest, and residents evacuated to high-lying areas.

        The cause of such flooding damage is that the rainwater pipe of the breakwater, which is made to allow rainwater to escape, is gradually submerged due to rising sea levels, so rainwater cannot escape. Since 2020, the height of the breakwater has been increased by 20cm, but it is said that waves continue to flow over.

        Due to rising sea levels, construction is underway to raise breakwaters in various places. Ongjin-gun, Incheon, carried out construction to raise the breakwater by 40-100cm in 2021. Mokpo City, Jeollanam-do, has built a 30-90cm breakwater between 2021 and 2022, but it is still not enough to block water, so it plans to build a 50cm height again. Residents of the area and officials of the public corporation say the cause of the waves is rising sea levels due to global warming.

 

​

​