The factors affecting landslide occurrence can be divided into two main groups, (a) Predisposing factors (intrinsic), such as slope, slope orientation, geology, and (b) stimulating factors (environmental), such as earthquakes, frost days, sudden heavy rainfall and human factors such as road construction, etc.
Lithology and distance from the fault zone maps using 1:10000 scales, and the geological sheet map of Kermanshah with 1:250000 scales were obtained, respectively Map of precipitation, temperature and frost days as well as climatic factors using data from stations within and near the study area was prepared in Arc GIS software.
Variables of land use, degree and orientation of slope, lithology, annual precipitation, temperature fluctuations, frost days, main roads and minor rural and regional areas as independent variables (input layer) were included in the model.
Global warming has reduced the number of frost days
, allowing the spread of harmful insects, such as the woolly adelgid that kills hemlock trees, and diseases transmitted by ticks and mosquitoes, he said.
Moreover, the summary predicts that warming will very likely persist into the twenty-first century, producing higher maximum and minimum temperatures, fewer cold days, and fewer frost days
over nearly all land areas, along with an increased risk of drought over most mid-latitude continental interiors.