Regional Climate Change Recorded in Moss Oxygen and Carbon Isotopes from a Late Holocene Peat Archive in the Western Antarctic Peninsula

• Published in: Geosciences
• Main Authors: Jonathan M. Stelling, Zicheng Yu
• Format: Article in Journal/Newspaper
• Language: English
• Published: MDPI AG 2019
• Subjects: stable isotopes; paleoclimate; Antarctic Peninsula; hydroclimate; temperature; Chorisodontium aciphyllum; Geology; QE1-996.5; Antarctic; The Antarctic; Litchfield; Litchfield Island; Antarc*
• Online Access: https://doi.org/10.3390/geosciences9070282; https://doaj.org/article/20d10fd168b04b72a7fa1fd26ff86ad2

The Antarctic Peninsula (AP) climate is characterized by a high degree of variability, which poses a problem when attempting to put modern change in the context of natural variation. Therefore, novel methods are required to disentangle sometimes conflicting climate records from the region. In recent years, the development of Antarctic moss-cellulose isotopes as a proxy for summer terrestrial growing conditions has become more widespread, with the isotopes Δ 13 C and δ 18 O reflecting moss productivity and peatbank moisture conditions, respectively. Here, we used a combined Δ 13 C and δ 18 O isotope analysis of moss Chorisodontium aciphyllum cellulose from a peatbank located on Litchfield Island in the western AP to document changes in climate over the last 1700 years. High Δ 13 C values (>15‰) indicate warm and productive conditions on Litchfield Island from 1600 to 1350 cal yr BP (350 to 600 AD) and over the last 100 years. The δ 18 O record shows two distinct intervals of dry conditions at 1350−1000 cal yr BP (600−950 AD) and at 500−0 cal yr BP (1450−1950 AD). Our record indicates that terrestrial ecosystems in the AP have responded to regional climate driven by atmospheric circulation, such as the southern annular mode (SAM) and, to a lesser extent, changes in ocean circulation.