| Popis: |
On 9th March, 2018, due to unusual rainfall and temperature rise, ice jam occurred in the Kenufuchi River which has never been seen before. In the future, it is foreseen that water disaster will become more frequent with climate change, and rivers where ice jam occurs in Hokkaido will increase. However, ice jam has few observation cases, and its mechanism is not sufficiently elucidated. In order to clarify the occurrence factors of ice jam for the Kenufuchi River, the authors conducted a calculation of river ice variation. As a result, it was found that ice jam occurred due to increase in temperature and increase in discharge. Furthermore, river ice is easily formed because the flow velocity decreases in floor stop installed in the KP 7.1, and ice jam occurs meandering section. In consideration of the influence of river narrowing, it was found that river ice was formed thicker and the scale of ice jam increased. |
