10 4

Reconstructing spring sea ice concentration in the Chukchi sea over recent centuries: insights into the application of the PIP25 index

Title
Reconstructing spring sea ice concentration in the Chukchi sea over recent centuries: insights into the application of the PIP25 index
Author
신경훈
Keywords
sea ice; HBIs; IP25; epi-brassicasterol; dinosterol; PIP25 index; Chukchi Sea
Issue Date
2019-11
Publisher
IOP PUBLISHING LTD
Citation
ENVIRONMENTAL RESEARCH LETTERS, v. 14, No. 12, Article no. 125004
Abstract
In this study, we aimed to reconstruct spring (April?June) sea ice changes in the western Arctic Ocean over recent centuries (ca. the last 250 years) by measuring biomarker distributions in a multicore (ARA01B-03MUC) retrieved from the Chukchi Shelf region and to evaluate outcomes against known or modelled estimates of sea ice conditions. Specifically, we analyzed for the Arctic sea ice proxy IP25 and assessed the suitability of a further highly branched isoprenoid (HBI) lipid (HBI III), epi-brassicasterol, and dinosterol as complementary biomarkers for use with the so-called phytoplankton marker-IP25 index (PIP25; PIIIIP25, PBIP25, and PDIP25, respectively). The presence of IP25 throughout core ARA01B-03MUC confirms the occurrence of seasonal sea ice at the study site over recent centuries. From a semi-quantitative perspective, all three PIP25 indices gave different trends, with some dependence on the balance factor c, a term used in the calculation of the PIP25 index. PIIIIP25-derived spring sea ice concentration (SpSIC) estimates using a c value of 0.63, determined previously from analysis of Barents Sea surface sediments, were likely most reliable, since SpSIC values were high throughout the record (SpSIC >78%), consistent with the modern context for the Chukchi Sea and the mean SpSIC record of the 41 CMIP5 climate models over recent centuries. PBIP25-based SpSIC estimates were also high (SpSIC 108%?127%), albeit somewhat over-estimated, when using a c value of 0.023 obtained from a pan-Arctic distribution of surface sediments. In contrast, PDIP25 values using a pan-Arctic c value of 0.11, and PIP25 data based on the mean biomarker concentrations from ARA01B-03MUC, largely underestimated sea ice conditions (SpSIC as low as 13%), and exhibited poor agreement with instrumental records or model outputs. On the other hand, PBIP25 values using a c factor based on mean IP25 and epi-brassicasterol concentrations exhibited a decline towards the core top, which resembled recent decreasing changes in summer sea ice conditions for the Chukchi Sea; however, further work is needed to test the broader spatial generality of this observation.
URI
https://iopscience.iop.org/article/10.1088/1748-9326/ab4b6e/metahttp://repository.hanyang.ac.kr/handle/20.500.11754/122110
ISSN
1748-9326
DOI
10.1088/1748-9326/ab4b6e
Appears in Collections:
COLLEGE OF SCIENCE AND CONVERGENCE TECHNOLOGY[E](과학기술융합대학) > MARINE SCIENCE AND CONVERGENCE ENGINEERING(해양융합공학과) > Articles
Files in This Item:
2019.11_신경훈_Reconstructing spring sea ice concentration in the Chukchi Sea over recent centuries_insights into the application of the PIP25 index.pdfDownload
Export
RIS (EndNote)
XLS (Excel)
XML


qrcode

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.

BROWSE