Author(s): Elena Dolgopolova
Linked Author(s): Elena Dolgopolova
Keywords: River Ice; River Ice Breakup and Jamming
Abstract: Mean air temperature increase is especially notable in the Polar regions: Alaska North Slope and Arctic coast of Russia. Ice is sensitive to alterations of air temperature, which provoke changes of the hydrological regime of pan Arctic deltas, since they are covered with ice the most part of the year. The pan Arctic deltas of the seven rivers are discussed: Pechora, Lena, Yana, Kolyma (Russia), Mackenzie (Canada), Colville and Yukon (USA). Annual discharges of the rivers at their delta’s heads were used as the indicator of the longterm change of the delta’s regime. Analysis of discharge alterations at the deltas under consideration shows the increase trend for all deltas. Ice jams are the characteristic feature for the northward flowing rivers. At all deltas and their tributaries the ice jams occur practically every spring, some of them cause hazardous inundation at the delta plains. The freeze-up period for the most of the deltas decreases depending on location of the delta from 5.5 to 2 days. The ice thickness also decreased by several cm. These changes are not considerable for the ~250 days ice seasons periods and ~2 m ice thickness, but such trends could have accumulated postponed effect. All the deltas suffer from sea surges and permafrost thawing and ground subsidence. Sea surges during open sea surface period result in flooding of the delta plain, salt water intrusion into delta branches, salting of the soils and coastal banks erosion. This study was carried out under Governmental Order to Water Problems Institute, Russian Academy of Sciences, subject no№ FMWZ-2022-0001.
Year: 2022