The vice president explained that super typhoon Mangkhut did not enter Vietnam

Deputy Director of Institute of Meteorology, Hydrology and Climate Change (Institute of Science and Technology and Climate Change) Mai Van Khiem gave an explanation about the trajectory of super typhoon Mangkhut.

According to Khiem, scientifically, the movement of storms depends on many factors: the guide line (subtropical high pressure), the inertia of the storm, the impact of terrain and friction .

Large waves hit the coastal area of ​​Heng Fa Chuen, Hong Kong residential area.(Photo: Reuters)

In particular, the strong storms, the role of the guide line is very important. The guide line usually exists in a period of about 3 days. This time, when the storm was still far away from the Philippines, the subtropical high pressure developed strongly, existing in the South.

If in fact the subtropical high pressure continues to be strong as in the early days, based on the calculation models, the storm has a westward deviation (ie, going to the west and northwest, towards Vietnam). However, 2-3 days later, the trajectory of the storm changes due to subtropical high pressure tends to withdraw to the North.

At that time, all forecast models of the US, Japan and Europe updated such atmospheric conditions. According to calculations, the trajectory of the storm follows the subtropical high edge, which has a deflection toward the North compared to the previous forecast (more north-west than the northwest).

Super storm in a row

Super typhoons appear near each other in the Atlantic region in 2017 as, and show a worrying fact about the relationship between the increase in storms with increasing intensity, appearing more and more often. piercing with climate change and global warming.

Not only in the South China Sea and the Pacific Northwest, storms also appear simultaneously on most oceans around the world in mid-September.

Satellite images on September 11 show a series of tropical cyclones operating globally in the tropics, including the super-typhoon Mangkhut in the Pacific Northwest and the very strong Florence storm in the Atlantic Ocean.

Statistics on 9/11 have 9 tropical cyclones (including storms, tropical depressions and depressions) operating globally, including such storms as super typhoon Florence, Helene, Isaac, storm Paul and Olivia, super typhoon Mangkhut .

A number of studies on the relationship between global warming and storm activity have found that very strong storms and super typhoons occur more frequently, especially in the Atlantic region.

Even some scientists believe that it may be necessary to propose an additional level 6 for hurricanes in the Atlantic (currently the highest level is level 5).

Difficulties in forecasting

Storm forecasting technology, especially for forecasting periods of 3 days or more, is built on the basis of digital prediction model.

Meanwhile, although there have been significant improvements in the orbital forecasting error of storms in the digital forecasting models, the models still have weaknesses that cannot be overcome, that is the prediction error. storm location is still great.

For more than 20 years, there has been almost no improvement in the ability to forecast storm intensity.

For the trajectory of the typhoon Mangkhut, the prediction of the model before the storm hit the Philippines is quite uniform.

However, after storming through the Ludong Island newspaper (from 7:00 on September 15), the projections of the model become dispersed, much different.

But there is a common trajectory between the orbits that predict the trajectory of the trajectory to fall to the right, predicting that Mangkhut storms land near Hong Kong and after landings will move more on land.

Due to friction with the land during the time and longer distance before reaching the border areas of Vietnam and China, the Mangkhut storm will weaken more before affecting North Vietnam.

Thus, the main danger from Mangkhut storm to Vietnam will be heavy rains in the North and Thanh Hoa areas, especially in the northern mountainous provinces.

It can be seen that climate change along with technological limitations, including the limitations of the forecasting model for the forecasting of the orbit and storm intensity, will also cause difficulties for storm forecasting. .