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- ItemTropical rainfall over the last two millennia: Evidence for a low-latitude hydrologic seesaw(London : Nature Publishing Group, 2017) Lechleitner, F.A.; Breitenbach, S.F.M.; Rehfeld, K.; Ridley, H.E.; Asmerom, Y.; Prufer, K.M.; Marwan, N.; Goswami, B.; Kennett, D.J.; Aquino, V.V.; Polyak, V.; Haug, G.H.; Eglinton, T.I.; Baldini, J.U.L.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.