Yesterday was the time to say goodbye and enjoy a last party with our
Korean friends. After a great dinner in an “all you can eat” sushi
place we went to a local brewery. I was surprised to see so many local
breweries in Gangneung with very good beers.
After
that, we went to a karoake place, which is a very popular thing to do
for party in Korea. I had a really great time in Korea and I will miss
the country, the food and especially the people. Thank you to all our
guests from the Korean Meteorological Administration for your
hospitality and your kindness, I will never forget my stay in Korea. I
would also like to thank my colleagues from the lab, in particular
Christophe Praz for his help during the campaign.
We had a free morning on Thursday 22nd, and Namwon kindly offered us a visit to the Woljeongsa Buddhist temple near Gangneung. Due to the snow fallen the day before, there was a really nice contrast between the white landscape and the bright colours of the building decoration.
Some figures of warriors, painted on the doors, stand guard at the entrance of the complex.
In front of the temple, we also had the opportunity to see the nine-story octagonal pagoda.
On the inside, the temple had a traditional structure, with large wooden columns, colorful decorations on the walls and an impressive statue of Buddha. Unfortunately we were not allowed to take pictures of this wonderful sight.
Two colleagues from my lab, Christophe and Alfonso, joined me on Sunday to help packing and shipping back the instruments. On Monday we prepared our radar for shipping and put it down from the roof with a crane.
It’s always a bit stressful to see the radar flying in the air! Then we put it on a truck and drove to Busan to supervise the shipping.
We were very impressed by the work of the shipping company who prepared three wooden crates for the instruments within 2 hours!
Now that everything is ready for shipping, we can enjoy our last Korean dinners.
We had six days of vacation between the Olympics and Paralympics, and I took this opportunity to visit the country by bike. The last time I was in Korea to prepare the campaign, in September, I started the “Seoul to Busan” bike trail along the Han and Nakdong rivers, and stopped in Daegu. This time, I decided to first finish this trip and bike from Daegu to Busan and then come back to Gangneung along the East coast. The green path on the map is what I completed in September and the blue and pink ones are what I did last week.
I discovered wonderful landscapes along the Nakdong and met a group of Korean cyclists for the last kilometres before reaching Busan.
There are very good bike infrastructures in Korea along the main rivers with a trail dedicated to bikes and without traffic. After that, I had to go back to Gangneung and decided to do the East coast trail which starts in Ulsan. It is also a wonderful itinerary which goes through all the fishing villages of the East coast with a spectacular view of the ocean.
It was a very good way to discover the country, the culture and the food. Koreans have a keen sense of hospitality, and I was always warmly welcomed, even though communication was mainly done with hands. It was a real adventure, especially the last two days as the East coast is quiet a long way to Gangneung.
For those who followed the games, you might have realised that the mountains were not covered with snow, like the Alps. This is not because of too warm temperatures, but rather because of the dry conditions prevailing in winter. This winter was especially very dry; they do normally get more snow. However, there was a heavy snowfall event between Wednesday and Thursday with 60 cm of fresh snow! This was THE event we had to catch with all our instruments, so we were under pressure to make sure that everything worked well, and it did! Below, you can see an RHI (vertical slice in the atmosphere) from our radar located in Gangneung. The event started with two layers of clouds: the first one below 1000 m, and the second one between 2000 and 5000 m. At this stage the reflectivity values are around 10 dBZ, hence the low precipitation intensity.
As the system evolves, the two layers merged into one precipitating cloud (a Nimbostratus) with heavy precipitation (Figure below)
The red layer with reflectivity values around 50 dBZ is what we call the melting layer: the layer where snowflakes melt into raindrops. Why is the reflectivity higher in the melting layer? Well, the melting snowflakes have roughly the size of normal snowflakes, but they get covered with liquid water as they melt. Reflectivity increases with size and is higher for liquid water than it is for ice. Therefore, melting snowflakes have a higher reflectivity. Below the melting layer, the melted snowflakes break-up into smaller raindrops, and hence the reflectivity decreases. In the figure below, you can see how the event evolved around 23:30 Korean time. What happened to the melting layer? Well, there is no melting layer, because it’s snowing at sea level in Gangneung! Indeed the temperatures dropped to around 0°C in the night, and it snowed until 3 am.
The following day, there was a lot of work at the Daegwallyeong weather station: removing the snow from the road, from the roof top, and most importantly, from the radars! Now, the PyeongChang area looks much more wintery! Too bad the Olympics are over, but we hope it will stay for the Paralympics!
On Sunday 23d, the winter Olympic games ended. I think it was a success, despite a few competitions being postponed. Switzerland collected 15 medals, which is 4 more than in Sochi: quiet impressive for such a small country! South Korea had 17 medals, which is 9 more than in Sochi. It looks like hosting the winter games motivated the winter sports athletes! The firework of the closing ceremony was pretty impressive, but it’s sad that the games are over.
However, science is not over and we expect strong precipitation on 28 Feb, so stay tuned!
Last week, I had to move one instrument to a site located close to the PyeongChang Olympic venues. It gets pretty cold in the evening, and screwing things become a real challenge. The benefit is that we had a nice view on the ski jumps, fireworks and even a lightning figures made by drones.
Since last week, I started having some kind of daily routines again. I acually have a working place in an open space office from the Korean Meteorogological Adminsitration in Gangenung Wonju National University, where our radar is located.
My Korean colleagues really made me welcome and I felt good in the office, even if don’t speak Korean. I even had to sing a song during the first day, according to the tradition or maybe they just wanted to make fun of me ;) The university is very nice, with some nature around it and a traditional pound.
I got back into some routines, like running at midday and having lunch with the colleagues. A Korean meal always consist of many side dishes and even in the cafeteria you get to have all these dishes on a special plateau with different compartments.
I am pretty impressed by the quality of the food at the cafeteria, maybe we should ask Le Vinci at EPFL to make Korean meals ;)
On February 16, at 15:34, Dario Cologna started the 15km free-style skiing to defend his two titles from Sotchi and Vancouver. After only 6km, he was already 11 seconds ahead of the former leader, and after 10km, he increased the gap to 23 seconds and he finally arrived 18 seconds ahead of the Norwegian Simen Hegstad Kruger. What an amazing race and what a great atmosphere in Alpensia!
On Wednesday, February 14, I was invited by the Swiss television (RTs) to speak about the meteorological conditions here in PyeongChang, and especially about the strong winds, which led to postpone a few competitions. The Taebek mountains are indeed very windy. The dominant weather situation in winter is a dry and cold northerly flow due to the Siberian High pressure system and moderate winds. However, occasionally, an upper level trough can cause a very strong jet stream and hence strong westerly winds at the surface. In addition, the fact that the PyeongChang region is kind of a pass in this mountain range induces wind convergence and thus increases the wind speed (Venturi effect). The situation on Wednesday was particularly strong, and the recorded wind speeds (mean of 40 km/h and wind gusts of 80 km/h) took place climatologically two days during the month of February. The weather chart below shows the analysis at 500hPa (about 5500m altitude). One can see an upper-level low (marked L on the chart) over north-eastern Siberia. Together with the high pressure (marked H) in the Pacific it creates a strong pressure gradient over Korea and Japan (the black contours are close together) and hence a strong westerly wind (winds are caused by pressure differences and in geostrophic approximation are parallel to lines of equal pressure).
By Thursday, the wind speed should have
decreased and we hope that the women’s slalom and biathlon competitions
that were cancelled will be able to take place. Stay tuned for more
weather news!
