Arctic climate changes have profoundly influenced the polar environmental changes in recent years.The Arctic Oscillation(AO),as a key component of the Arctic climate system’s internal variability,affects the source t...Arctic climate changes have profoundly influenced the polar environmental changes in recent years.The Arctic Oscillation(AO),as a key component of the Arctic climate system’s internal variability,affects the source to sink processes and interactions across the multilayer Arctic system by regulating the land,ocean,sea ice,and atmospheric processes.The East Siberian Arctic Shelf(ESAS)has experienced significant changes in the input,transport,and burial of sedimentary organic carbon(OC)due to climate warming and shifts in the AO phase in recent decades.This study analyzes grain size,total organic carbon(TOC),total nitrogen(TN),and stable carbon isotope(δ^(13)C)in two sediment cores from the ESAS to reconstruct the burial record of OC over the past few decades and examine the response mechanism of sedimentary OC records to regional-scale climate forcing.The results show that the OC in the two sediment cores originates from mixed sources with a dominant terrestrial contribution.In the LV83-28 core from the Laptev Sea,the TOC and TN contents have increased at an accelerated rate since the 1990s,with a noticeable rise in the contribution of terrestrial OC.This trend is linked to an increase in terrigenous input caused by the positive AO phase.Core LV83-39 in the East Siberian Sea could have accumulated more terrestrial OC transported along the continental shelf during the positive AO.This implies that,under the interannual regulation of the AO regime,the input and crossshelf transport of terrigenous OC in the ESAS showed consistent sedimentary responses.This finding could enhance the understanding of the burial mechanism of sedimentary OC and its environmental response to regional climate change.展开更多
基金The National Natural Science Foundation of China under contract Nos 42130412 and 42376068the Fundamental Research Funds for the Central Universities under contract No.202241001+2 种基金the Ocean Negative Carbon Emissions Program and the Taishan Scholar Program under contract No.TSQN20182117the Russian Scientific Foundation under contract No.21-77-30001the Ministry of Science and Higher Education of the Russian Federation under contract Nos 124022100083-1 and 124022100084-8.
文摘Arctic climate changes have profoundly influenced the polar environmental changes in recent years.The Arctic Oscillation(AO),as a key component of the Arctic climate system’s internal variability,affects the source to sink processes and interactions across the multilayer Arctic system by regulating the land,ocean,sea ice,and atmospheric processes.The East Siberian Arctic Shelf(ESAS)has experienced significant changes in the input,transport,and burial of sedimentary organic carbon(OC)due to climate warming and shifts in the AO phase in recent decades.This study analyzes grain size,total organic carbon(TOC),total nitrogen(TN),and stable carbon isotope(δ^(13)C)in two sediment cores from the ESAS to reconstruct the burial record of OC over the past few decades and examine the response mechanism of sedimentary OC records to regional-scale climate forcing.The results show that the OC in the two sediment cores originates from mixed sources with a dominant terrestrial contribution.In the LV83-28 core from the Laptev Sea,the TOC and TN contents have increased at an accelerated rate since the 1990s,with a noticeable rise in the contribution of terrestrial OC.This trend is linked to an increase in terrigenous input caused by the positive AO phase.Core LV83-39 in the East Siberian Sea could have accumulated more terrestrial OC transported along the continental shelf during the positive AO.This implies that,under the interannual regulation of the AO regime,the input and crossshelf transport of terrigenous OC in the ESAS showed consistent sedimentary responses.This finding could enhance the understanding of the burial mechanism of sedimentary OC and its environmental response to regional climate change.
