Landslides are extremely dangerous in areas where people live besides hills. And they pretty much always happen without a warning, although some signs can be observed. How come we still didn’t figure out ways to predict landslides reliably? Can satellites solve this problem once and for all? A team of scientists from UK and China set out investigating this possibility.
Last week a massive landslide struck Xinmo Village, Maoxian County, Sichuan Province in China, because heavy rain washed out some more stable ground. The rubble was estimated to be about eight million cubic meters – a massive amount of land moved onto 1,600 meters of road and 2 km section of river. Two days late another landslide happened in the region and soon after– a third one. The share volume of this natural disaster made scientists and locals think, how come such a massive event could not be predicted on time?
Scientists took data collected by ESA’s Sentinel-1 satellite radar mission – a program of two polar-orbiting satellites. Before and after pictures were analysed to see if the disaster could have been predicted beforehand and if that would’ve made a difference. In other words, could satellites serve for early warning. Traditional techniques cannot predict landslides accurately, because someone actually has to visit the site. Meaning, there already have to be some signs, which would indicate the need of specialist evaluation. Satellites operate day and night in all-weather conditions and so could be more useful in this way.
Scientists were able to use data to detect and map the active landslide over a wide region, identifying the source and the boundaries of the landslide. They say that early alarm system could actually be automatic, because basic signatures of active landslide are not too hard to identify with current satellite systems. In fact, scientists detected 10 other active landslides in the same region while conducting their research. Zhenhong Li one of the authors of the study, said: “If we can detect movement at a very early stage then in many cases it is likely we would have time put systems in place to save lives”.
Many people live in areas prone to landslides. Predicting more dangerous natural disasters would provide them with peace of mind and potentially would save their lives. The really good thing is that all the technology is readily available and just has to be arranged, tested and proved.
Source: Newcastle University