Processing of aerial photographs in geoinformation systems for constructing models of possible flooding zones in a flood-prone period

The natural and geological conditions of the Khabarovsk Territory determine the specificity of any region, characterized by the annual occurrence of spring mash phenomena, their gradual transition to the summer-autumn flood-hazardous period and the departure into winter with a high water level. Forecasting the scale of possible flooding of territories is the basis for early response of the forces and means of the Unified State System for the Prevention and Response of Emergency Situations (RSChS) The paper discusses the professional experience of specialists from the Crisis Management Center of the Main Directorate of the EMERCOM of Russia for the Khabarovsk Territory in preparing models of possible flooding of settlements applying the QGIS geographic information system during the flood-prone period of 2021 in the Khabarovsk Territory. The authors identify peculiarities of the unmanned aerial vehicles used to predict areas of possible flooding such as the need for early aerial photography of human settlements; dependence of the quality of orthophotomaps on the experience of specialists performing aerial photography; variability of coastline relief; dependence on weather conditions; short period, favorable for aerial photography; inaccessibility of settlements; location of settlements in the border area. The matching of models obtained with the help of QGIS with the actual situation developed during the 2021 flood crest was identified. Also, some peculiarities and disadvantages were defined despite the positive experience of forecasting by modeling flood zones (flooding).