HR: 0800h
AN: C31B-0334    [Abstracts]
TI: Forecast models of Arctic coastal changes during the next 100 years
AU: Pavlidis, Y A
EM: pavlidis@geo.sio.rssi.ru
AF: P.P. Shirshov Institute of Oceanology, RAS, Nahimovskiy prospect 36, Moscow, 117997 Russian Federation
AU: Leontyev, I O
EM: leontyev@geo.sio.rssi.ru
AF: P.P. Shirshov Institute of Oceanology, RAS, Nahimovskiy prospect 36, Moscow, 117997 Russian Federation
AU: Nikiforov, S L
EM: nikiforov@geo.sio.rssi.ru
AF: P.P. Shirshov Institute of Oceanology, RAS, Nahimovskiy prospect 36, Moscow, 117997 Russian Federation
AU: * Rachold, V
EM: vrachold@awi-potsdam.de
AF: Alfred Wegener Institute for Polar and Marine Research, Telegrafenberg A43, Potsdam, 14473 Germany
AU: Grigoriev, M N
EM: grigoriev@mpi.ysn.ru
AF: Permafrost Institute, Siberian Branch, RAS, Yakusk-18, Yakutsk, 677018 Russian Federation
AB: Predicted global climate warming will significantly effect Arctic coastal dynamics due to the reduction of the sea-ice cover, the amplification of wave processes and the degradation of coastal permafrost. This poster presents scenarios of Arctic coastal changes based on forecast models for the next 100 years. The results indicate that the most essential changes will take place within permafrost environments. Starting in the Norwegian Sea and moving eastward, the results are summarized in the following. In the Norwegian and Barents Seas coastal changes will be minimal. In the Pechora Sea, in the Varanday area, the total sediment flux to the sea from coastal erosion will increase up to 5 million tons per year. In the Kara Sea a longer ice-free period will promote the amplification of wave processes. Thus, within the northern part of Yamal Peninsula the estimated shoreline retreat rates will reach 2.2 meter per year during the first half of the next century and 3.4 m per year during the second half. At the end of the century the average shoreline retreat rates will be 2.5-2.6 times higher than today. In the Laptev Sea the total activity of wave processes will increase by a factor of 1.5-2.0. By the end of the 21st century the estimated rates of thermoabrasive processes for example at Muostakh Island and Shirokostan Peninsula will be 1.25-1.4 times higher than today and average coastal retreat rates will reach 6.4 m per year. Shirokostan's shoreline will retreat 550-600 m and the associated sediment flux will increase up to 18-21 million tons per year, which is comparable to the modern fluvial sediment discharge. In the East Siberian Sea the destruction of the long-term sea-ice cover in the offshore area (100-400 km) could be activated. Thermoabrasive processes are likely to increase by a factor of 4. Using mathematical modeling the increase of thermoabrasion at the Crestovskiy Cape can be predicted as 2.6-4.3 m per year during the first part of the century and 3.4-5.2 during the second part, which is equivalent to a total increase by a factor of 1.4-1.5. In the Chukchi Sea any catastrophic destruction of accumulative bars is not expected but the average wave height in the near shore zone will increase from 1 m to ca. 3 m, corresponding with a twice longer wave period. As a result, the relief of onshore bars will significantly change and new coastal accumulative banks could be formed. This study has been performed under the framework of the Arctic Coastal Dynamics (ACD) project and was supported by INTAS (grant no. 2001-2332).
DE: 4207 Arctic and Antarctic oceanography
DE: 4546 Nearshore processes
DE: 1815 Erosion and sedimentation
DE: 1823 Frozen ground
SC: Cryosphere [C]
MN: 2004 AGU Fall Meeting