Loading...
The flood season has arrived, and we are ushering in the most "excited" and "irritable" time of the year. Heavy rain, strong winds, thunder, hail...... The news of the "raging" of strong convective weather has begun to frequently swipe the screen again, and its abrupt appearance, violent destructive power, and diverse forms of disasters have impressed everyone.
Tomorrow is the "National Disaster Prevention and Mitigation Day", and what is the highest and most destructive meteorological disaster during the flood season? What is the difference between colorful meteorological disaster warnings and early warning signals that often appear at the same time? What is the weather like during the critical period of "seven up and eight down" in Chengdu this year? At this special juncture, the reporter interviewed Kang Xue, a senior engineer of the Chengdu Meteorological Observatory.
Warning issued: the weather is "quiet"
Warning Signal Issued: Take defensive measures now
When the weather suddenly "changes face" and may cause harm, the meteorological department usually issues a meteorological disaster warning or early warning signal to inform everyone in advance to take corresponding precautions.
For example, on April 28, the Municipal Meteorological Observatory issued a yellow warning for gale and a blue warning for strong cooling, and on April 29, it issued a blue warning signal for high winds, what is the difference between the two?
"Meteorological disaster early warning and early warning signals are the key parts of the meteorological disaster prevention and mitigation early warning system, and they are also two different types of forecasting and early warning." Kang Xue explained that first of all, the two issuing units and responsible areas are different. The early warning is generally issued by the meteorological department at or above the municipal level, and the early warning signal is issued by the meteorological department at the city and county levels.
Secondly, the types and functions of meteorological disaster forecasting are different. The early warning is mainly issued for 11 types of disastrous weather, including heavy rain, strong wind, strong cooling, high temperature, fog, haze, low temperature, heavy snow, frost, freezing and drought. The early warning signals are mainly issued for 14 types of disastrous weather, such as heavy rain, heavy snow, strong cooling, strong winds, sandstorms, high temperatures, drought, thunder and lightning, thunderstorms and strong winds, hail, frost, fog, haze, and road ice.
Thirdly, the timeliness of the two is different. Compared with early warning signals, early warnings are more time-sensitive. The timeliness of the early warning is generally more than 24 hours, and the early warning signal is more urgent than the early warning, and the timeliness is generally within 12 hours. Therefore, when the warning is issued, the weather may not change for the time being, and it will appear "quiet"; Warning signals are warnings of imminent or ongoing disaster weather, so they are more urgent.
In short - "If you see a warning signal from the meteorological station, you must take defensive measures immediately!" ”
Late mid-July to early August
The duration of high temperature and the range of high temperature are too large
According to statistics, in 2023, Chengdu will issue a total of 17 warnings of severe weather, the top three are heavy rain, high temperature and strong cooling warnings, and a total of 47 early warning signals will be issued, and the top three are high temperature, heavy rain and strong wind warning signals. In addition, the data shows that in recent years, the number of high temperatures, heavy rains, thunder and lightning, gale warnings and early warning signals issued in Chengdu has shown an increasing trend. The summer in Chengdu is mainly concentrated from June to August, when the weather is hot, the water vapor is abundant, and thunderstorms are prone to occur, so there are frequent warning signals for high temperatures, heavy rain and thunderstorms.
In February 2021, we encountered the hottest day in the same period in history, and spent the "summer" in the "Spring Festival" for the first time, the average temperature of our city was 3.8 °C higher than normal, breaking the highest record in the same period in history, and most places entered spring on February 4, the earliest since 2000;
On August 7~24, 2022, there was a high-temperature weather process with the most extreme and intensity since the complete meteorological record in our city, and the maximum temperature of the national meteorological observation stations in all districts (cities) and counties exceeded the historical extreme;
In 2023, the two records of "the warmest year since the beginning of meteorological observation records on the mainland" and "the warmest year since meteorological records have been recorded in the world" will be achieved;
At the beginning of 2024, the temperature will remain "high", and the average temperature in Chengdu will be higher than the same period in history...... "extreme weather" is appearing more and more frequently in our lives. According to the forecast, the temperature will rise significantly on the 13th, hitting 30 °C again, and the pace of summer is getting closer and closer, will it be unusually hot this year?
Kang Xue analysis pointed out that the average temperature of the city is expected to be 26.0 °C in midsummer (July ~ August) this year, 0.3 °C higher than the same period of the year (25.7 °C).
In general, the duration and range of high temperatures this year are still more than those in normal summer, so it is necessary to pay attention to preventing the adverse effects of high temperature on human health and make preparations in advance for energy supply in peak summer.
"Seven up and eight down" towns are prone to waterlogging
There is a possibility of watershed flooding in Jintang
According to the Sichuan Provincial Department of Water Resources, Sichuan Province officially entered the flood season on May 1. It is expected that the overall deviation of the climatic conditions in the province during the flood season (May ~ September) this year will be heavier than drought, and regional and periodic flood disasters will be obvious.
As far as Chengdu is concerned, the Chengdu Flood Control and Drought Relief Headquarters will conduct dynamic research and judgment according to the weather conditions in April, and if the strong weather occurs earlier, it will be announced on April 28 this year that it will officially enter the flood season.
According to the experience of the past years, the first half of July and the end of August are the most concentrated time periods of flood conditions in Chengdu every year.
"It is expected that during the flood season this year, the precipitation in our city will be one percent more than that of the same period in normal years." Kang Xue said that in early summer, most places have meteorological drought, heavy rainstorms and floods in the flood season, strong convective weather is frequent, and there are regional rainstorm weather processes 5~7 times.
Among them, in early July, late July to early August, late August there are periods of heavy precipitation, systematic continuous precipitation is more than convective precipitation, it is expected that there will be 4~6 times of regional rainstorms, the western mountainous areas and Longquan Mountain are prone to local landslides and debris flows and other geological disasters, cities and towns are prone to waterlogging, Jintang has the possibility of basin floods.
In addition, the reporter learned that the meteorological department will closely follow the whole chain of three-dimensional monitoring, forecasting and early warning, and linkage response of disastrous weather to make various preparations, and strictly adhere to the first line of defense for disaster prevention and mitigation.
Chengdu Daily Jinguan News Reporter Wang Jingyu Photo / Video Municipal Meteorological Observatory Editor-in-charge Liu Yang Editor Wang Ling