A Wetter Arctic Coincident With Hemispheric Warming 8,000 Years Ago

E. K. Thomas, I. S. Castañeda, N. P. McKay, J. P. Briner, J. M. Salacup, K. Q. Nguyen, A. D. Schweinsberg

Research output: Contribution to journalArticlepeer-review

29 Scopus citations

Abstract

Arctic precipitation is predicted to increase this century, with dramatic consequences for high-latitude systems. Observations remain spatiotemporally limited, hampering determination of the forcings causing wetter Arctic conditions, although two mechanisms have been proposed: enhanced local evaporation and greater poleward atmospheric moisture transport. Here a subcentennial-resolution multiproxy lake sediment record from western Greenland sheds light on these mechanisms. Cool summers throughout the Northern Hemisphere and in western Greenland 9 to 8 ka are associated with aridity in this region, via reductions in local evaporation and in meridional moisture gradients, which suppressed poleward moisture transport. Summers became more humid starting 8.1 ka, mainly due to increased evaporation from warmer Arctic seas but also to increased poleward moisture transport caused by hemispheric warming. This record provides independent support for predictions of both enhanced local evaporation and increased poleward moisture transport causing wetter Arctic summers in step with global ocean and atmosphere warming.

Original languageEnglish (US)
Pages (from-to)10,637-10,647
JournalGeophysical Research Letters
Volume45
Issue number19
DOIs
StatePublished - Oct 16 2018

Keywords

  • Arctic
  • Holocene
  • branched glycerol dialkyl glycerol tetraether
  • hydroclimate
  • leaf wax hydrogen isotope
  • moisture transport

ASJC Scopus subject areas

  • Geophysics
  • Earth and Planetary Sciences(all)

Fingerprint

Dive into the research topics of 'A Wetter Arctic Coincident With Hemispheric Warming 8,000 Years Ago'. Together they form a unique fingerprint.

Cite this