Opal (Zn/Si) ratios as a nearshore geochemical proxy in coastal Antarctica

Katharine R. Hendry*, Rosalind E. M. Rickaby

*Corresponding author for this work

Research output: Contribution to journalArticle (Academic Journal)peer-review

26 Citations (Scopus)

Abstract

[1] During the last 50 years, the Antarctic Peninsula has experienced rapid warming with associated retreat of 87% of marine and tidewater glacier fronts. Accelerated glacial retreat and iceberg calving may have a significant impact on the freshwater and nutrient supply to the phytoplankton communities of the highly productive coastal regions. However, commonly used biogenic carbonate proxies for nutrient and salinity conditions are not preserved in sediments from coastal Antarctica. Here we describe a method for the measurement of zinc to silicon ratios in diatom opal, (Zn/Si)(opal), which is a potential archive in Antarctic marine sediments. A core top calibration from the West Antarctic Peninsula shows (Zn/Si)(opal) is a proxy for mixed layer salinity. We present down-core(Zn/Si)(opal) paleosalinity records from two rapidly accumulating sites taken from nearshore environments off the West Antarctic Peninsula which show an increase in meltwater input in recent decades. Our records show that the recent melting in this region is unprecedented for over 120 years.

Original languageEnglish
Article number2218
Number of pages12
JournalPaleoceanography
Volume23
Issue number2
DOIs
Publication statusPublished - 18 Jun 2008

Keywords

  • ZINC
  • VI ICE SHELF
  • CONTINENTAL-SHELF
  • WEDDELL SEA
  • BIOGENIC SILICA
  • MARINE-SEDIMENTS
  • ELEMENTAL COMPOSITION
  • PENINSULA
  • CLIMATE-CHANGE
  • SOUTHERN-OCEAN

Cite this