Rock gathering: the first software for accurate prediction of mudslides has been developed in the Russian Federation

Russian scientists have developed a mathematical model for predicting mudslides. It has a higher accuracy than existing analogues, since in addition to weather conditions, the degree of friability of the material is also taken into account in the calculation. This reduces the probability of error to 0.006%. The development can be used both for forecasting natural disasters in mountainous areas and for predicting landslides in Central Russia, where landslides have become more frequent due to unprecedented rainfall. According to experts, soil collapses will occur more frequently here due to climate change caused by global warming. Therefore, the development of mathematical models of these processes is extremely relevant.

Forecast of mudslides

Scientists from Ural Federal University, together with Chinese specialists, have developed a mathematical model for accurate prediction of mudflows. The software can be used both for forecasting natural disasters in mountainous areas and for assessing the condition of slopes in lowland regions of the Russian Federation, where landslides have become more frequent due to high rainfall. The program will help identify critical thresholds for precipitation and the energy of loose material — the power accumulated in the soil, over which a mudflow forms.

— Mudflows are a constant challenge for predicting natural disasters due to their highly unpredictable triggering mechanisms, which can be influenced by many factors. Usually, warning systems rely only on precipitation, but we have found that the risk of mudslides increases significantly when the energy of loose material exceeds 3 billion J/m2, and the maximum daily precipitation is 27 mm. At the same time, both conditions are necessary for the occurrence of a mudflow: without the first factor, the second practically does not lead to an event. Thanks to our research, the accuracy of the forecast has increased significantly: the average error was only 0.006%, which is 4 thousand It is several times less than that of similar models," said Nikita Fomin, co—author of the study and director of the UrFU Institute of Construction and Architecture.

While mudslides occur regularly in mountainous areas, the number of such emergencies in central Russia has increased only in recent years, due to a noticeable increase in precipitation, said Igor Shkradyuk, coordinator of the industrial greening program at the Wildlife Conservation Center.

This is the result of global warming, climatologist Alexander Chernokulsky, deputy director of the Obukhov Institute of Atmospheric Physics of the Russian Academy of Sciences, told Izvestia in an interview.

— Another thing is that the new atmosphere contains more moisture. Storm clouds rise higher, and more water is poured into the rains. That is, the amount of rain that pours out of one thunderstorm cloud is getting bigger. There is more warm air in which there is more moisture due to global warming," he added.

For example, on July 21, heavy rains caused a landslide in the Tsaritsyno district of Moscow, where part of the lawn was washed away onto the roadway. And on July 15, a similar incident occurred on Leninskaya Sloboda Street.

— To apply the model in non-mountainous areas, it will need to be adjusted. The behavior of ground masses under external influences — water, high humidity or other additional load — is additionally set and taken into account in calculations," Nikita Fomin added.

Soil properties

Scientists tested a mathematical model that takes into account the mobile potential energy and the total energy of loose sediments in mudflow beds on the data of 159 mudflow foci in the Nujiang River basin (Yunnan Province, China). The research was conducted throughout the year. For the first time, the analysis helped to identify the current patterns: with the energy of loose material (soils) >3.12 billion J/m2, the risk of mudslides increases sixfold. At the same time, a decrease in precipitation from 29.5 mm to 27 mm reduces the threat by 59%.

In areas with high energy of loose material, scientists recommend additionally installing temperature and steam pressure sensors: these parameters can significantly increase the risk of mudslides when local thresholds are exceeded. In the near future, the model will be adapted for other regions.

— The thresholds depend on the geology, but the approach is universal. For example, for the Urals or the Caucasus, they can be calculated based on local data," said Nikita Fomin.

The mathematical model obtained by the researchers surpassed the 13 used reference models for predicting mudflows.

"Creating mathematical models for predicting mudslides is always important, as they cause great damage, and in order to avoid it, such natural disasters should be predicted whenever possible," said Peter Shibalin, director of the Institute for Earthquake Prediction Theory and Mathematical Geophysics at the Russian Academy of Sciences.

Climate change leads to an increase in the amount of precipitation coming to earth and its unevenness, including in the central part of Russia. Water penetrates the soil, the soil swells, and landslides occur on hillsides and river banks. These changes are not taken into account in any way in the regulatory framework for construction in the country. To solve the problem, it is necessary to revise the standards for the bearing capacity of slopes and slopes. You can also refuse to mow grass in potentially dangerous areas, then the roots would be better restrained by the soil. This would help reduce the risk of landslides, Igor Shkradyuk summed up.