"As a forecaster, I hope I can understand the secret and draw the forecast closer to the reality." Sun Jun, the chief forecaster of the Central Meteorological Observatory, has been a forecaster all his life, from a handsome young man to an old comrade with white temples. From using pencils to using artificial intelligence, he has been understanding the secret all his life.
On December 1, 2023, Sun Jun judged the closing ceremony weather of the Pacific Games at the Solomon Islands Meteorological Bureau. Figure/Jing Hao
Exploration-the scientific mystery in the clouds
"Experienced ups and downs, find the law in the changing situation. When the forecast is successful, it is not too joyful; When the forecast fails, don’t be too upset, and constantly explore and improve the forecast. " Sun Jun said.
After doing one thing all his life, Sun Jun thought about it for a while and simply gave the word "worth it".
"The flood in Jilin in 2010, the torrential rain in Beijing on July 21, 2012, the torrential rain in Henan in 2021, and the extreme rainstorm in Beijing, Tianjin and Hebei in 2023 …" Talking about the past, many weather processes are clearly visible in Sun Jun’s mind.
He often gets to the bottom of the weather. And this curiosity began from childhood. When I was a child, Sun Jun saw a neat cloud boundary in the dark sky: the sky was overcast on one side and Wan Li was clear on the other. He is full of curiosity: what is this?
This "why" continues to work. "Dealing with the weather is also my initial intention to explore scientific issues." Sun Jun said.
Find problems in forecasting, solve problems in scientific research, and apply research results to business, thus further improving forecasting accuracy. Sun Jun observed, discovered, analyzed and verified over and over again, and carried out a cycle from forecasting to scientific research to forecasting.
In July, 2021, due to the rich water vapor brought by the typhoon landing, a torrential rain occurred in Henan. Sun Jun and his team once included the rainstorm affected by typhoon landing in the research scope.
……
Time and time again, the scientific research topics were condensed-warm rainstorm, typhoon rainstorm and extreme rainstorm. Sun Jun and his team found clues of scientific problems from the forecast process.
After continuous research, scientific research has also made a series of progress. In the diagnosis of extreme rainstorm, the water vapor condition, dynamic condition and thermal condition are diagnosed and analyzed, and the abnormal meteorological factors causing extreme rainstorm are screened.
In 2023, the forecast accuracy reached a new high, and the score of 24-hour rainstorm increased to 98% compared with the mainstream model, reaching the highest level in history.
It is the confidence brought by continuous exploration that allows him to confidently give the conclusion that "it won’t rain" in the face of complex weather situation in the forecast of Hangzhou Asian Games.
Responsibility-Forecast and Early Warning in Storm
"I always say that human life is related to the sky, and the sky here refers to the weather." Weather is closely related to the safety of life and property. Therefore, he has a strong sense of mission and responsibility. "If the forecast is accurate, we can better prevent and respond, and we can keep safe." Sun Jun said.
In order to catch up with time, he is always the first to arrive at work when he is on duty. "Sun Jun is a respected old forecaster and very dedicated." Zhang Tao, chief forecaster of the Central Meteorological Observatory, said.
Sun Jun recalled the flood in Jilin in July 2010, and was faced with the judgment of whether the reservoir needed flood diversion and whether the dam needed blasting. "This is a major test." After careful analysis, Sun Jun and his colleagues accurately judged the precipitation level.
In July 2023, a rainstorm occurred in Beijing, Tianjin and Hebei. Sun Jun "recalled" the weather process in his memory, thinking that it was similar to the "July 8" rainstorm in Henan, and it was extremely extreme, so he raised the forecast precipitation. Later, it was proved that this adjustment was correct.
With global warming and frequent extreme weather, many data exceed the extreme value, which breaks through the forecaster’s original cognition and increases the difficulty of forecasting.
Adhering to a scientific and rigorous attitude, Sun Jun is not afraid to challenge the numerical model prediction. "It’s always calm when things change." Yang Shunan, chief forecaster of the Central Meteorological Observatory, commented on Sun Jun this way.
Colleagues gave Sun Jun a nickname, "Sun 500", which came from a bold and cautious forecast. From June 17th to 21st, 2010, a rainfall process occurred in the northeast of Jiangxi. Sun Jun gave the forecast conclusion of the maximum precipitation of 500mm. This is a bold forecast, which is much higher than the conclusion of the numerical model. After analysis and verification, his prediction conclusion is accurate. Sun Jun teased that if the forecast was not accurate, it would be called "Sun 250".
"Because there is always uncertainty in forecasting, there is always pressure." Under the calm appearance, Sun Jun also has his own pressure. On many nights when rain is predicted, he will wake up and look at the sky. On the day of duty, he will be slightly gaunt when he is full of energy.
Pursuit-the precision of time and space
In the late 1980s, Sun Jun joined the Central Meteorological Observatory. On the topographic map with provincial boundaries, Sun Jun draws the weather map with a 2B pencil and red and blue pencils. "At that time, there was a lack of forecast data and there was no precipitation data to refer to. A clever woman can’t cook without rice. " Sun Jun said.
With the development of science and technology, with the blessing of satellites, radars and automatic weather stations, the observation data and information are more abundant. "The temporal and spatial resolution of the forecast is more refined." Sun Jun said.
The technology is changing, and Sun Jun’s love for forecast maps remains unchanged. "Drawing weather maps is a pleasure." In his view, synopsis is a subject dealing with data. In order to better compare historical cases in forecasting, Sun Jun keeps the weather maps and key physical quantities of many weather processes in mind.
"To be an excellent forecaster, you need not only excellent professional knowledge, but also knowledge of astronomy, geography, politics and economics." The understanding of social economy also enables Sun Jun to better serve the weather forecast in production and life. Before Spring Festival travel rush this year, Sun Jun predicted the cold wave weather in advance. Considering the impact of road icing on Hubei, Henan, Anhui and other places, he recorded an interpretation video.
In 2025, Sun Jun reached the age of retirement. At present, in addition to doing a good job in weather forecasting, he has also shifted his focus to personnel training: leading the team to tackle key scientific research problems and teaching … Liu Yi, the global meteorological office of the Central Meteorological Observatory, said, "There is laughter everywhere."
At the same time, Sun Jun also participated in global monitoring, forecasting, service and other work, making forecasts in a larger world and passing on his experience to more people.
"Now, the pursuit of weather forecasting is fixed-point, fixed-time and quantitative. As long as the accuracy rate has not reached 100%, we must continue to explore and be a dream catcher forever." Sun Jun said.
(author:Xu Nenyu Editor: Zhang Lin)