Remote Sensing Now Used for Landslide Mapping
Remote Sensing is now used for landslide mapping. Traditionally, a field survey would be conducted to assess and map landslide. However, depending on how large the area is where the landslide occurred, the process could become very difficult and expensive. With technology advancing every day, remote sensing is now capable of replacing field surveying because it is easy to use and allows operators to access areas that are otherwise inaccessible.
What Satellites work best? Some satellites that work best are Landsat 7, Terra, QuickBird, Envisat, and SPOT.
How many methods are used and what are they? There are 6 different remote sensing techniques used in landslide analysis; Optical VHR, SAR, GB-InSAR, TLS, UAV-DP, and IRT. These are types of spaceborne platforms; meaning they can fly. Also, methods can be combined with different algorithms to get results.
What are some advantages and disadvantages of using remote sensing methods? Advantages include a lower cost than the traditional methods, as well as high resolution data, and the ability to cover a wide study area in a short amount of time. Another advantage is being able to see in inaccessible areas. Disadvantages include some satellites only having the ability to see during a certain time of day or type of weather and having little penetration of heavy vegetation.
Where can it be used? Remote sensing for landslide susceptibility mapping is most used in tropical high elevation climates with lots of rainfall. I focused on three different areas of the world in my study: Ethiopia, Malaysia, and Japan.
Which Parameters are most determined? How many are recommended to use in a study? The most common parameters determined were lithology, slope angle, aspect, land-cover, and drainage patterns. Precipitation, soil biomass, and distance to urban features and geological structures were also found. However, two or three are recommended to use in a study, because the more parameters you set, the broader your result will be.
Who Benefits? Many people benefit from using remote sensing to conduct landslide analysis and mapping. These include emergency response teams, public safety teams, the analysis operators, and the citizens living in the area. Overall, by using remote sensing, safety is promoted, keeping the analysis operators and emergency response teams safe from hazardous conditions. Also, using remote sensing can aid in rapid analysis of the affected area. With this rapid analysis, emergency response teams can go to help the victims of the disaster, and the victims get help. Loved ones can also check to see if they had family or friends in the disaster.
Finally, Public safety teams can perform the right precautions to block off the area so it can be rebuilt and cleared.
Devonee Shearer is a Junior at West Virginia University studying Geography and Environmental Geoscience. She is also a member of Maptime Morgantown, the YouthMappers affiliated chapter at WVU.