Reconstruction of autumn sea ice extent changes since AD1289 in the Barents-Kara Sea, Arctic  

作　　者：Qi ZHANG Cunde XIAO Minghu DING Tingfeng DOU 

机构地区：[1]Institute of Polar Meteorology, Chinese Academy of Meteorological Sciences [2]State Key Laboratory of Earth Surface and Resources Ecology, Beijing Normal University [3]College of Resources and Environment, University of Chinese Academy of Sciences

出　　处：《Science China Earth Sciences》2018年第9期1279-1291,共13页中国科学（地球科学英文版）

基　　金：supported by the National Natural Science Foundation of China (Grant No. 41425003);the Strategic Priority Research Program of the Chinese Academy of Sciences (Grant No. XDA19070103);the Basic Research Project of Chinese Academy of Meteorological Sciences-Base Construction of Polar Atmospheric Sciences for Field Observation;the Scientific Research Foundation of the Key Laboratory of Cryospheric Sciences (Grant No. SKLCS-OP-2016-03)

摘　　要：Using high-resolution ice core and tree ring proxies for sea ice extent （SIE）, we reconstructed a robust time series of autumn SIE over the Barents-Kara （B-K） sector of the Arctic from AD 1289-1993. After intercomparing the results and statistical parameters using the ordinary least squares regression （OLSR）, the principle component regression （PCR） and the partial least squares regression （PLSR） methods, SIE time series were synthesized into a more robust series using the weighted average method, which used the explained variances as weights. The results showed that from the end of the 13th century to the end of 18th century, the autumn B-K SIE was large, with large variations and a slightly expanding trend overall. This reflected significant multideeadal oscillations under the Little Ice Age （LIA） background. The B-K SIE began to decrease at the end of the 18th century, and a shrinking trend became significant during the second half of the 19th century, which lasted into the 1930s- 1940s. The 1930s-1940s was a period with a relatively low SIE in the B-K Sea, and the SIE had a short period of expansion from the 1940s-1970s. However, the B-K SIE has continuously and significantly shrank since the 1970s. The reduction in the B-K SIE since the end of the 18th century has been unprecedented in both duration and speed over the last 700 years. The B-K SIE has retreated significantly since the 1970s, with a speed 6.18 times greater than the former mean retreating speed. The industrial revolution may be a dominant factor in this result. The Arctic SIE in recent years may be the lowest it has been over the last millennium.Using high-resolution ice core and tree ring proxies for sea ice extent(SIE), we reconstructed a robust time series of autumn SIE over the Barents-Kara(B-K) sector of the Arctic from AD1289–1993. After intercomparing the results and statistical parameters using the ordinary least squares regression(OLSR), the principle component regression(PCR) and the partial least squares regression(PLSR) methods, SIE time series were synthesized into a more robust series using the weighted average method, which used the explained variances as weights. The results showed that from the end of the 13 th century to the end of18 th century, the autumn B-K SIE was large, with large variations and a slightly expanding trend overall. This reflected significant multidecadal oscillations under the Little Ice Age(LIA) background. The B-K SIE began to decrease at the end of the18 th century, and a shrinking trend became significant during the second half of the 19 th century, which lasted into the 1930 s–1940 s. The 1930 s–1940 s was a period with a relatively low SIE in the B-K Sea, and the SIE had a short period of expansion from the 1940 s–1970 s. However, the B-K SIE has continuously and significantly shrank since the 1970 s. The reduction in the B-K SIE since the end of the 18 th century has been unprecedented in both duration and speed over the last 700 years. The B-K SIE has retreated significantly since the 1970 s, with a speed 6.18 times greater than the former mean retreating speed. The industrial revolution may be a dominant factor in this result. The Arctic SIE in recent years may be the lowest it has been over the last millennium.

关 键 词：ARCTIC Sea ice Ice core Tree rings PALEOCLIMATOLOGY Global warming 

分 类 号：P731.15[天文地球—海洋科学] X591[环境科学与工程—环境工程]