Dataset Information

Tropical rainfall over the last two millennia: evidence for a low-latitude hydrologic seesaw.

ABSTRACT: The presence of a low- to mid-latitude interhemispheric hydrologic seesaw is apparent over orbital and glacial-interglacial timescales, but its existence over the most recent past remains unclear. Here we investigate, based on climate proxy reconstructions from both hemispheres, the inter-hemispherical phasing of the Intertropical Convergence Zone (ITCZ) and the low- to mid-latitude teleconnections in the Northern Hemisphere over the past 2000 years. A clear feature is a persistent southward shift of the ITCZ during the Little Ice Age until the beginning of the 19th Century. Strong covariation between our new composite ITCZ-stack and North Atlantic Oscillation (NAO) records reveals a tight coupling between these two synoptic weather and climate phenomena over decadal-to-centennial timescales. This relationship becomes most apparent when comparing two precisely dated, high-resolution paleorainfall records from Belize and Scotland, indicating that the low- to mid-latitude teleconnection was also active over annual-decadal timescales. It is likely a combination of external forcing, i.e., solar and volcanic, and internal feedbacks, that drives the synchronous ITCZ and NAO shifts via energy flux perturbations in the tropics.

SUBMITTER: Lechleitner FA

PROVIDER: S-EPMC5381098 | biostudies-literature | 2017 Apr

REPOSITORIES: biostudies-literature

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Tropical rainfall over the last two millennia: evidence for a low-latitude hydrologic seesaw.

Lechleitner Franziska A FA Breitenbach Sebastian F M SF Rehfeld Kira K Ridley Harriet E HE Asmerom Yemane Y Prufer Keith M KM Marwan Norbert N Goswami Bedartha B Kennett Douglas J DJ Aquino Valorie V VV Polyak Victor V Haug Gerald H GH Eglinton Timothy I TI Baldini James U L JU

Scientific reports 20170405

The presence of a low- to mid-latitude interhemispheric hydrologic seesaw is apparent over orbital and glacial-interglacial timescales, but its existence over the most recent past remains unclear. Here we investigate, based on climate proxy reconstructions from both hemispheres, the inter-hemispherical phasing of the Intertropical Convergence Zone (ITCZ) and the low- to mid-latitude teleconnections in the Northern Hemisphere over the past 2000 years. A clear feature is a persistent southward shi ...[more]

PMID: 28378755

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Dataset Information

Tropical rainfall over the last two millennia: evidence for a low-latitude hydrologic seesaw.

Publications

Tropical rainfall over the last two millennia: evidence for a low-latitude hydrologic seesaw.

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