[News UP] 40cm on my way to work, big snow again...Will it stop in the afternoon?

■ Host: Anchor Yoon Jae-hee, Anchor Cho Jin-hyuk
■ Video call: Anti-Sung YTN Disaster Advisory Committee

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

[Anchor]
The snow will continue until today. Let's connect the anti-Sung YTN Disaster Advisory Committee to find out more. Commissioner, you're out, right?

[semi-spanning]
Hello,

[Anchor]
More than twice as much snow as yesterday. I fell into my legs in the snow that was piled up below my knees. Why are there so many people coming?

[semi-spanning]
First of all, the biggest thing is that the fairly hot sea and cold low pressure met to create a snow bomb. The biggest cause is climate change. With the heat wave this year, the sea temperature has risen very high. This seems to have had the biggest impact. As the Siberian high pressure comes down, and the dry and cold air comes down, the sea is very warm. It is about 2 degrees higher than usual, but as it came down to the sea, the snow cloud belt made of the sea level developed quite strongly.

As the strongly developed snow cloud band flowed into the land, a weak pressure valley was being created on the land side from Gangwon-do to Gyeonggi-man Bay. Snow flowed deep inland along the barometric valley, that is, deep into Seoul or Gangwon-do, and atmospheric instability is formed in these barometric valleys. Therefore, as the snow clouds that developed strongly on the ocean side landed on land due to atmospheric instability, it became a factor that developed even stronger, and the record-breaking, almost current central observation areas received enormous snow enough to renew the maximum temperature. In fact, if the intensity of snow is at this level, I think that heavy snow in the central part of the country, not in areas with topographical heavy snow such as the west coast or the east coast, can fall once in 200 years.

[Anchor]
It is said that it is the most snow bomb in November since the first snow and weather observation, but why did it snow so much?

[semi-spanning]
First of all, I think the overall warming had the greatest impact. So the air was warm, and the air in the south was. Then the water temperature of the sea and the sea temperature in the west were very high. But as the very cold and dry air came down in this state, the snow clouds created on the sea side developed quite strongly. It develops strongly due to convection, and the larger the air difference between cold air and sea temperature, the stronger the snow cloud develops. However, in this case, the air from the north was very cold, but the seawater temperature was quite high.

As a result, it developed much higher, and as I said earlier, the second is that one trough was located in the metropolitan area. As a result, air instability was created here as it collided with the cold air in the north and the warm air from the south. As a result, powerful snow clouds from the sea come back to land and develop more powerfully toward the metropolitan area. As a result, there was a lot of snow that was hard to predict so far.

[Anchor]
This heavy snow is falling because the sea level temperature was 1 to 2 degrees higher than the average year. This analysis is also coming out now, but does this difference in sea level by about 1 degree have a big impact on the weather?

[semi-spanning]
That's right. The change in the atmospheric temperature of 1 degree in seawater is much scarier than the change in the atmospheric temperature of 1 degree because of the large heat capacity. This is because it can store a lot of heat. The easiest thing we can say in meteorology is that an increase of more than 1 degree in ocean temperature can increase water vapor in the atmosphere by more than 7%. In fact, the sea temperature on the west coast was about 2 degrees higher than usual this time. The highest was about 3 degrees, the lowest was about 1 degree, which is unusual, but at this high rate, we could have supplied a lot more water vapor.

In December or January, the sea temperature itself decreases, so there is less room to supply water vapor into this air, but in this case, the sea temperature in the West Sea is still high, and it is higher than usual. As a result, we were able to supply much more water vapor, but once we make a typhoon when the sea temperature is 1 degree high in the ocean, the wind speed increases by about 32 kilometers per hour. So, 1 degree of the ocean has a significant impact on the development of nuclear power plants, storms, typhoons, and then this increase in precipitation and heavy snow.

[Anchor]
A lot of snow of more than 40cm has already accumulated in the central part of the country, and wet snow of 1 to 5cm per hour is still falling, so how much has this come in terms of the precipitation of the rainy season?

[semi-spanning]
First of all, when we look at conventional theory and construction, conventional theory is usually 10:1. So if it snows 40cm, it's 40mm in terms of rain. Next time in the case of construction, this time it was customary. Construction is usually viewed as 30:1. So if the snow falls about 30cm, I think it fell about 10mm in terms of rain. In fact, the difference between conventional theory and construction is very large. First of all, in the case of wet snow, one of the many reasons why various structures collapse and such accidents occur is that this wet snow itself contains a lot of moisture, so it is heavy because it is dense. It doesn't come off easily either.

Once attached to trees, they rarely fall, so trees break or telephone poles are stretched out. In particular, there are a lot of snow removal right now, but even in the case of snow removal, it is very difficult to actually remove snow in the case of customs. Because the volume of water is high overall, it is difficult to treat. If it melts and freezes, you have to break it. However, in the case of construction, it is very easy to clean up. As I said earlier, the amount is low in density, so even if you just push it, it disappears, so there is a big difference between various customs and construction.

[Anchor]
By the way, isn't most of the snow in Korea a habitual snowstorm? What do you think?

[semi-spanning]
When it falls below minus 10 degrees Celsius, it is called wet snow, and when it falls below minus 10 degrees Celsius, it is construction from then on. In Korea, construction often falls when a cold wave comes down. So, even for snow entering the West Sea, construction sometimes falls when the ground temperature drops from minus 10 to 20 degrees Celsius. There were also cases where construction fell earlier this year. So all the snow in Korea is a custom? I'm afraid not. However, especially in this case, snow falling between 0 and -10 degrees is called wet snow. In this case, if you get close to 0 degrees, so -10 degrees, won't you get closer to construction? Since the humidity gets lower in the atmosphere. However, since zero degrees can contain the most water vapor at the temperature at which snow begins to form, this snow is the wettest, with the highest humidity.

[Anchor]
It's a more worrisome situation because it's a heavy wet snow, but there are still heavy snow warnings and warnings in place in most inland areas. How much more snow will fall in the future?

[semi-spanning]
First of all, until today, it is expected to fall more than 5-10cm in the metropolitan area, Chungcheong, Gangwon, and Jeju, and more than 15cm in places where it falls a lot. It is expected to be 3-8cm in the eastern part of Jeollabuk-do and 2-7cm in the northern part of Gyeongbuk. And to the south, so it is expected that it will usually rain because the temperature is high during the day in the flat area, not the mountain side.

[Anchor]
You've explained about the wet snow in detail. Isn't it literally humid snow? So it would be much heavier than construction, so how much does it specifically weigh?

[semi-spanning]
It's usually just a common practice. In the case of wet snow, it is said that it usually weighs 600kg if it is 10m wide, 10m long, and 1cm high, but for example, 20cm has accumulated now. Then, if you say 10m and 20cm stacked 10m wide, it weighs about 1.2 tons. Because something very heavy presses from above, greenhouses and weak facilities collapse.

[Anchor]
Not only is it heavy, but it seems to be more dangerous because of its clumping properties, so wouldn't it be a collapse accident that builds up on the building?

[semi-spanning]
That's right. It is not easily removed. In the case of construction, if you just sweep it with a broom, it will get swept away, but in the case of wet snow, it remains the same. So it's very difficult to remove snow on the roof or in a greenhouse. So what are these really the most representative characteristics of practice and construction? In the case of wet snow, the snow that can make a snowman is called wet snow. Doesn't it stick together well? However, in the case of construction, it is very thin and weak in density, such as rice flour.

So those things don't even make your eyes clump up when we have a snowball fight, those eyes. It's very heavy, and it clumps up well, and then melts at the bottom. It has the characteristic of freezing as it is when melted. As a result, it is not removed anymore, and in the case of wet snow, it melts, so if you remove snow on roads, doesn't it melt? It melts, and when the temperature drops a little at night, it freezes immediately or turns into what we call black ice. That's why it has a very bad influence.

[Anchor]
Since it has been snowing and stopping all over the country since yesterday, the vicious cycle of melting snow by spraying snow removal agent and then freezing it again is repeated. I think we need to pay a lot of attention to traffic safety, what do you think?

[semi-spanning]
That's right. In this case, I think it's best to pay attention to traffic safety from myself. The most important thing is slow travel. It's the most important thing to go around slowly. Second, when we drive in snow or ice, we start at 2nd stage if it's manual, and when it's automatic, isn't there an auto hold? It's important to get this right. It's safest to follow the road the car in front of you next time you're on the road. Next time when it's downhill like this, don't use a hand brake and make sure to use an engine brake. In the case of uphill roads, you have to go up constantly, and if you take a break in the middle, you are very likely to be pushed back or have an accident like this. And I would like to specifically recommend that drivers prepare snow tires or winter equipment will be very helpful for safe driving.

[Anchor]
You said that you need to thoroughly prepare for snow damage. However, I have a lot of questions about the snow this time. It feels like it rains locally in summer. Can snow fall like that, too?

[semi-spanning]
That's right. The principle is the same. In summer, rain clouds made by receiving a lot of water vapor from the West Sea land on the land, but when you look at the land, cold air comes down from the north and warm air is located at the bottom, doesn't atmospheric instability become strong? As a result, this rain cloud band from the West Sea becomes powerful as it lands on land, showing a pattern. As a result, this is a pattern of local heavy rain, which used to fall 140mm per hour in Gwanak-gu, Seoul.

That's the case this time, too. Even if a snow cloud made on a warm sea with very cold air from the sea comes in, it will also record a huge amount of snowfall. As I said earlier, in this case, there was actually a pressure trough from Gangwon-do toward Gyeonggi-do for two consecutive nights. The fact that the trough is created means that the cold air from the north comes down and there is warm air at the bottom. Then the atmosphere is very unstable here. As a result, the air that came in last night developed more strongly toward southern Gyeonggi-do, which entered Seoul or Gangwon-do, so this heavy snow actually falls.

In fact, because of the temperature difference between winter and summer, so the temperature is high in summer, so you can get quite a lot of precipitation, but isn't it winter now? Therefore, the absolute amount is small because the amount of water vapor that can be contained in the air is small, but if the air pressure pattern like yesterday is considered in summer, it can be considered that Baekam, which has come a lot now, or Geumjeong, has rained more than 400mm in places over 40cm.

[Anchor]
It is said that Seoul accumulated the most snow this November. It's been 117 years since the weather observation. In the meantime, many people must have thought of Gangwon-do, but where was the reason why it snowed more in the west than in the east and in the metropolitan area?

[semi-spanning]
In the case of Korea, the East Coast region has the most heavy snow and the second frequency is the West Coast region. It's Jeolla and Jeju on the west coast, but the reason why these areas fall so much is because of the topographic influence. When high pressure expands to the west in winter, heavy snow usually falls on the west coast of Chungnam, Jeolla, and Jeju Island. When this high pressure moves eastward, the east wind enters and heavy snow falls in the east coast, and the amount of heavy snow in the east coast is much higher. Heavy snow in these areas occurs several times every year.

However, it is very rare for heavy snow to fall in Seoul or inland Gangwon, and it is a case where a trough of atmospheric pressure comes in order for heavy snow to fall in this area. The troughs come in and get down, but the troughs come down from the Shandong Peninsula from the north and pass through, so the troughs coming down from the north don't snow that much in the central part of the country. Therefore, this case is very unusual. In the central region, especially yesterday morning, it is mainly in the metropolitan area and Gangwon Province. And last night and today, isn't it concentrated in southern Gyeonggi Province and Chungcheong Province?

The places that fall the most. The biggest reason for this is because, as I told you right away, a powerful snow cloud from a hot sea surface landed on land and encountered a land-based, land-based trough. Since the barometric bone was formed, I've been a forecaster for quite a long time, and it's my first time seeing it. Of course, it's my first time. Since it's a record. So I think it's a very rare case.

[Anchor]
If so, can we say that there is a good possibility that there will be more heavy snow in the metropolitan area or in the western part of the country like yesterday and today?

[semi-spanning]
As I told you, didn't you break the overall observation record this time? So, I think this is about 200 years in frequency. So, it can be seen as a frequency that can occur about once every 200 years, but with recent climate change, the frequency of this occurrence is getting shorter and shorter. So it's not very likely that the same air pressure pattern will be created. There are many patterns like the Siberian high pressure, for example, where the low pressure is located in the upper part of Vladivostok and the cold air comes down, but this is not a form that often occurs when the sea temperature on the West Sea is very high and the pressure bone is weakly formed in the central part of the country on the way down. But anyway, I think it's more likely that these things will happen more often in the future than before.

[Anchor]
Since the first snow is like this, I'm worried about this winter, but there's another snow news early next week. Will it snow in this winter?

[semi-spanning]
I don't think so. Isn't the snow that came this time really unusual? But I have news of snow next Monday, and I don't expect this much snow at that time. I think a lot of places will fall about 5 to 10cm. Then, the pressure trough itself does not last as long as it does now, but it is expected to escape to paper. The problem is that the cold will come down on the 26th and last for a long time.

For the time being, the temperature will rise slightly because the barometric pressure will come in next Monday, but it is temporary and the weather will continue to be below zero for the time being, so the minimum temperature will continue until the weekend of next week. So since it's this cold, I want you to be careful not to have an accident like this.

[Anchor]
Anyway, this snow continues today and some areas will fall until tomorrow. If the snow is piled up like this, the weather will be important for snow removal. After that, will the weather be okay on Friday, Saturday, and Sunday weekends without any news of snow?

[semi-spanning]
First of all, only Chungcheong, Jeolla, Gyeongbuk, and Jeju are expected to see snow tomorrow, but the amount of snow is not much tomorrow. It's peak until today. Then, the day after tomorrow, the west coast of Jeolla, Jeju, and tomorrow's metropolitan area can snow lightly overnight in the afternoon. I expect that much. However, there is no news of snow from daytime to Sunday on the weekend, nationwide. Even if there is no news of snow, the snow that is currently falling freezes, so it's good to keep it as it is during the day. As I said before, in the case of humid snow, heat can be lost from the ground if there is a lot of humidity, radiant cooling.

So, if it starts to freeze at night, this is the road. It's all melted because we've done snow removal and sprayed snow remover, but there's a high possibility that it's frozen for the time being on the roads where ordinary people pass. And I fell yesterday in Sangam-dong, and I fell. This is the case of black ice. When cars melt and then freeze slightly, the ice or snow cannot be seen through the eyes, perhaps because it is the color of the road. That's why there was an accident, but I also had accumulated yesterday and melted where the snow was removed, so I thought it was a stone. I didn't have eyes, so I pointed at the stone because I was touching it, but I just fell. I think there will be a lot of accidents like this. So I think the elderly should be careful when they go out.

[Anchor]
I hope the center director is not seriously injured. Lastly, can you point out the overall weather forecast for this winter?

[semi-spanning]
First of all, the forecast for the Korea Meteorological Administration this winter will be similar to the average for December and January. It released a three-month forecast last week that February will be warmer than usual. What we should think about here is that it's similar to the average year, it's warmer than the average year, then we shouldn't think that this winter won't be cold. What this is is very volatile. This means that November and December are similar to normal because they average out a month, but that's not to say there's no cold. So, in the meantime, a huge cold wave can come, and after the cold wave ends, a huge abnormal change can come.

By averaging all of these, December is similar to the average year and January is similar to the average year, but the temperature volatility in the meantime is expected to be quite large this winter. What I mean is that it's cold and then hot again. I think it's going to be a winter where the cold and hot periods don't go as short as before, but change longer and longer. So, I think it is important to never think that this winter is not cold and to properly prepare for the cold.

[Anchor]
I need to prepare well so that I don't get any eye damage. So far, I've been with YTN Disaster Advisory Committee and Anti-Sung Commissioner.

[semi-spanning]
Thank you.