[News Special Report] For the second day in the Seoul metropolitan area, "Snow Bomb"...Until when should I get off?

■ Host: Park Seok-won, Um Ji-min, Anchor
■ Video broadcast: Professor of Environmental Engineering at Keimyung University in Gimhae-dong

* The text below may differ from the actual broadcast content, so please check the broadcast for more accurate information. Please specify [YTN News Special] when quoting.

[Anchor]
I looked into the heavy snow situation and damage news by region. This time, we will connect with an expert to find out more about the weather situation. Professor Kim Hae-dong of the Department of Environmental Engineering at Keimyung University is connected. You're out, right?

[Kim Hae-dong]
How are you?

[Anchor]
The place where it fell a lot came up to the knee level of an adult man, how much snow did it fall last night?

[Kim Hae-dong]
That's right. In many places, it's over 40cm, so I think it's up to the knee level. It's the result of falling since last night, a little lull during the day, and heavy snow again from the evening.

[Anchor]
I thought it would get better today. How long will it continue to snow?

[Kim Hae-dong]
As the news just went out, the heavy snow warning has been lifted, hasn't it? However, according to the Korea Meteorological Administration's forecast data, additional snow is expected to fall again by Friday morning, and the place where it falls a lot is about 15cm in southern Gyeonggi-do, so it seems that it is not yet a stage to be relieved.

[Anchor]
The problem is that with the snow piled up for two days, if it gets colder, it may freeze as it is, so what is the temperature today?

[Kim Hae-dong]
There are a lot of accidents like the collapse of buildings due to this snow. This is a habit, that is, it means that the snow is heavy. As snow fell on the boundary line where it could snow or turn into rain, heavy snow called wet snow fell. If you look at the temperature this time, in Seoul, Gyeonggi-do, and the metropolitan area, the highest temperature during the day is about 4 to 5 degrees, so some snow may melt, but it falls below zero again at night. In that case, it is more dangerous to drive or walk because the snow melts and freezes again while turning into water, rather than staying on the side of the road. Freezing becomes more dangerous in this state where the temperature rises during the day and then drops at night rather than staying below freezing during the day.

[Anchor]
You said the practice is unusual, but let's talk about it later. What's unusual is that it's rare for the first snow to fall so much. Does this much snow have anything to do with climate change?

[Kim Hae-dong]
Looking at the snow this time, it seems that the two causes overlap. First, a chill comes down from the interior of Siberia, evaporates water in the West Sea, and the evaporated water meets cold air in the sky and turns into snow. So when it snows in this way, it usually does not snow toward Seoul or inland, but mainly on the west coast coast, but this time, it is very closely related to the change in air pressure patterns this winter. Because the Siberian high pressure was formed far south compared to the
plain year, the wind did not blow northwest, but closer to the west wind.

As a result, the snow made in the West Sea did not only stay on the west coast, but also dug deep inland. But that alone can't explain the large amount of snow that fell this time. It is called the Joint Low Pressure, which fell from the upper western wind, and a low pressure was formed in the northwest of Korea. So even this role of raising the cold air coming from the north was overlapped with a lot of snow, especially this snow not only on the coast, but also on the inland.

[Anchor]
There's a snow forecast for next week, is there a possibility that it'll fall as much as this time?

[Kim Hae-dong]
Considering what the snow will look like next week, we need to see if the two factors will overlap this time. The cold air that will come down after next Tuesday is expected to be several degrees lower in temperature than the cold air that came this time. Therefore, you may be concerned that more water vapor will evaporate in the West Sea when this air comes down. Since the sea temperature in the West Sea has a cooling effect due to this cold wave, the sea temperature in the West Sea decreases a little, but instead, the cold air force from the north becomes a little stronger.

Therefore, it is said that the difference in temperature between the surface temperature of the sea and the cold air coming down from the north, the difference in the temperature of the sea, the difference in temperature between the sea and the temperature. The wider the temperature difference, the more snow it has. But I think the effect will be smaller than this time. However, the problem is whether the joint low pressure, which had a large snowfall in the inland area, will appear next time, so we should be careful about this. I think it's a little too early to say definitively. I think we should watch that carefully.

[Anchor]
Professor, it snowed a lot in Seoul this time. However, based on the cumulative snowfall, Gwanak-gu came to over 40cm and Seongbuk-gu came to about 27cm, but why does it vary so much depending on the region?

[Kim Hae-dong]
It's a characteristic of precipitation, but it's 40cm of snow, so you can think of it as a huge precipitation.If it rained, it had to be multiplied by one-tenth. So if 40cm of snow fell, it's about 40mm in rain. So even when it rains, it doesn't fall evenly in the Seoul area, but there is a lot of difference depending on the place. In that sense, the snow this time is about twice as different locally, but I don't think it's such a strange phenomenon to have such a difference.

[Anchor]
Didn't you talk about the professor's habit earlier? How heavy is the wet snow compared to the average eye?

[Kim Hae-dong]
In terms of mass ratio, it depends on how wet it is, but in severe cases, the difference is about three or four times. When it's very cold, the snow falls so soft that it doesn't stick together well. In the case of snow like this one, it is slightly melted, so it can be considered that the snow is condensed. So it's a lot heavier than construction because the volume is contracted.

[Anchor]
The damage seems to be greater because the snow is heavy, so how should I deal with it to reduce this damage?

[Kim Hae-dong]
Wouldn't it be hard to urgently repair the facilities when it snows like this? However, as the global temperature continues to rise in the future, there is a possibility that there will be more humid snow than construction. So I think it would be a good way to prepare in advance with this in mind. And if the facilities are not good, evacuation is the best way.

[Anchor]
Since it's been snowing heavily since the beginning of winter, many people seem to be worried about how cold it will be this winter and how much snow it will fall. Professor, didn't you predict the strongest wave to drop to minus 18 degrees Celsius this year?

[Kim Hae-dong]
I'm not saying it's 18 degrees. This year, the La Niña phenomenon began in the summer, not only in the Korea Meteorological Administration but also in Japan, and around the world, I thought it would strengthen a lot in winter. Therefore, if the characteristics of La Niña are strong, a cold wave will prevail in winter. I talked about the possibility. And a representative case of very cold and snowy due to the La Niña phenomenon was the Korean wave in 2022, two years ago. It went down to minus 18 degrees Celsius, and heavy snow fell in Honam and Jeju Island, causing a traffic disturbance and an air disturbance.

When I introduced such cases, I think Koreans understood that summer is a heat wave of more than 40 degrees, and the 18 degree cold wave that we experienced in 2021 when we think of winter. Recently, however, the Korea Meteorological Administration (KMA) issued an amendment on November 24th that this winter is not as cold as originally expected and is expected to be warmer than previous years or previous years. But what you have to understand correctly is that if you average it by adding all the temperatures that will appear over three months, it is likely to be higher than in previous years.

However, if you look at the upper weather map, the factors that create the cold wave coming down from the north, such as this cold wave, are lined up as they go west. So I'm not saying that this winter will continue to be warm, but this cold and before this cold, the autumn weather was very warm. So, I think we should accept it like this, with very warm weather and temperature falling in turns. So I think it would be more correct to accept it like this because if you average high temperature days and cold temperature days at the same time, it approaches almost zero.

[Anchor]
It's getting harder to predict and predict the weather, but it's December soon. Will it continue to be cold below zero in the future?

[Kim Hae-dong]
If you look at it again this time, the cold will go to Friday and tomorrow, and from the weekend to Monday and Tuesday, warm weather will continue to exceed 10 degrees again. Then, after Tuesday, the cold air approaches even colder than this time. And by the end of the year, it is expected that a cold wave will fall below minus 5 degrees Celsius in the third and fourth weeks of December.

[Anchor]
The heavy snow warning has been lifted. However, there are places where snow is piled up everywhere, and there are cases where it freezes again in the evening, so what are the countermeasures that should be taken right now?

[Kim Hae-dong]
In this case, there are a lot of stories such as black ice, and I think it is very important for related authorities to carefully examine the freezing conditions of roads and to give attention to traffic control or to drastically reduce the driving speed of vehicles. And it's better to keep in mind that people who have to walk on the street can fall at any time so that they don't have their hands in their pockets or anything like that. I think it's best not to do outside activities if possible.

[Anchor]
I see. Let's stop here. So far, I was with Kim Hae-dong, a professor of environmental engineering at Keimyung University. Thank you.