On Dec. 10, supporters of President Yoon Suk-yeol hold a rally against impeachment near the presidential residence in Hannam-dong, Yongsan-gu, Seoul, where a cold wave warning was in effect in most regions across the country. /Courtesy of News1

Supporters of President Yoon Suk-yeol and protesters calling for his impeachment have been holding overnight protests in front of the presidential residence in Hannam-dong, Yongsan District, Seoul, since early this month.

On the morning of the 10th, about 100 people either in favor of or against President Yoon's impeachment stayed overnight. The lowest temperature in Seoul that morning was minus 12 degrees. Amid the season's harsh cold wave, citizens have provided "warming buses" and "aluminum foil blankets" to help endure the frigid temperatures.

◇For 900,000 won a day, charter a bus for a 'warming bus'... Inside, it exceeds 20 degrees

About 100 supporters of President Yoon participated in an overnight rally organized by the "New Liberal Coalition" and stood guard near the presidential residence in Hannam-dong until morning. Some set up tents to greet the morning. Around 30 people also stayed overnight, urging President Yoon to step down. Although the lowest temperature in Seoul that morning was minus 12 degrees, the strong winds in Hannam-dong, located between Namsan and the Han River, made it feel even colder.

Inside the 'heating bus' operating at the Yoon Suk-yeol supporters' rally near the presidential residence in Hannam-dong, Yongsan-gu, Seoul, on Dec. 10, the internal temperature rises to 21.8 degrees as the engine starts and warm air blows out. /Courtesy of Jeong Du-yong

One of the measures is a chartered bus referred to as a "warming bus." That afternoon, around 2 p.m., there were two large tour buses for President Yoon's supporters on Hannam-daero. One large tour bus and one medium-sized bus were for participants calling for impeachment. The warming bus is provided by personal donors who offer it for use by rally participants.

Kim Mo (63), the driver of the bus used as a warming bus, explained that he usually receives about 1.1 million won for operating a chartered bus from Seoul to Busan, but he charges around 900,000 won for running it as a "warming bus" including fuel costs.

By around 6 p.m. that day, both warming buses for the pro-President Yoon rally were in operation. Although the outside temperature was frigid, the engines were idling, blowing warm air inside the buses, and the internal temperature rose to 21.8 degrees. One bus, which can accommodate up to 45 people, had 21 sitting inside. An elderly person in their 70s had earbuds in, listening to a YouTube broadcast with their eyes closed, while four people in their 30s were discussing the political situation. The warming buses were allowing for a natural exchange of users, with people warming themselves for about 20 to 30 minutes before leaving. A "Democratic Coalition warming bus" specifically for female participants was also separately provided.

During the 'Emergency Action for the Arrest of Yoon Suk-yeol' held near the presidential residence in Hannam-dong, Yongsan-gu, Seoul, on Dec. 5, citizens including progressive organizations such as the Korean Confederation of Trade Unions and the Justice Party hold cheering sticks demanding the arrest and detention of President Yoon Suk-yeol, while staying warm under 'emergency blankets'. /Courtesy of News1

◇As soon as wrapped in 'aluminum foil blanket,' legs feel warm... Insulation material blocks cold from the ground

"Aluminum foil blankets" gained fame after photos were released of protestors calling for President Yoon's impeachment, wrapped in them while encountering heavy snowfall on the 5th. They have been nicknamed "Kisses Group" due to their resemblance to chocolate "Kisses."

Aluminum foil blankets can be purchased for under 1,000 won each from online shopping malls. Despite their thinness making them seem less warm, their effectiveness is immediately noticeable when used. When a reporter wrapped themselves in an aluminum foil blanket on the road in Hannam-dong around 4 p.m., warmth was instantly felt in their legs. The temperature inside the blanket rose to 11.2 degrees.

The aluminum foil blanket is made by coating a thin plastic sheet with a layer of aluminum. It was developed in 1964 by the National Aeronautics and Space Administration (NASA) for the Apollo lunar exploration program. Hence, it is also referred to as a "space blanket." It can rapidly prevent body temperature from dropping, and marathon runners often use it after a race to avoid hypothermia.

On Dec. 10, at the site of the Yoon Suk-yeol supporters' rally near the presidential residence in Hannam-dong, Yongsan-gu, Seoul, insulation material IsoPink is placed on the asphalt road. /Courtesy of Jeong Du-yong

Heat is transferred in three ways: convection, conduction, and radiation. Aluminum foil blankets block radiation to create a warming effect. Kim Sang-wook, a professor of physics at Kyunghee University, explained in a Facebook post that "radiation is electromagnetic waves, which are reflected by metals," adding that "the aluminum (wrapped around the blanket) reflects the infrared rays emitted from the body to preserve body heat."

Insulation materials such as isopink used in building construction serve to block the cold rising from the ground, as they are laid under asphalt roads. After days of use by protesters, the corners have become worn. Isopink performs better in insulation than Styrofoam.

On Dec. 10, at a cafe near the presidential residence in Hannam-dong, Yongsan-gu, Seoul, supporters of President Yoon distribute coffee and drinks that were 'prepaid'. /Courtesy of Jeong Du-yong

◇'Prepayment' moved to Hannam-dong… Donations of cup noodles and fish cake

'Prepayment,' which had been seen in front of the National Assembly ahead of the vote on President Yoon's impeachment, has moved to Hannam-dong. Supporters of President Yoon quickly adapted to the prepayment culture. In a café in Hannam-dong that day, a notice was posted next to the tablet menu board stating that “the People Power Party Emergency Response Committee Minor Gallery donated 500 cups of yuja tea and 300 cups of Americano” and “Liberty Unification donated 100 cups of Americano.”

There is also a 'food truck donation.' Supported by the online community "Misi USA," the food truck that came to Hannam-dong is distributing fish cakes to protesters calling for Yoon's impeachment. The food truck owner, Lee Mo (33), stated, "I came out yesterday and consumed 1,600 fish cakes. Today, I brought 2,000."

Supporters of President Yoon were sharing cup noodles provided through donations. Volunteer Lim Mo noted, "We pour hot water into the cup noodles and distribute them every 24 hours," stating that "eight volunteers have been coming out since 10 days ago."