@Article{CamposCPMKPVACB:2019:NeMeMi,
author = "Campos, Mar{\'{\i}}lia C. and Chiessi, Cristiano M. and Prange,
Matthias and Mulitza, Stefan and Kuhnert, Henning and Paul,
Andr{\'e} and Ven{\^a}ncio, Igor Martins and Albuquerque, Ana
Luiza S. and Cruz, Francisco W. and Bahr, Andr{\'e}",
affiliation = "{Universidade de S{\~a}o Paulo (USP)} and {Universidade de
S{\~a}o Paulo (USP)} and {University of Bremen} and {University
of Bremen} and {University of Bremen} and {University of Bremen}
and {Instituto Nacional de Pesquisas Espaciais (INPE)} and
{Universidade Federal Fluminense (UFF)} and {Universidade de
S{\~a}o Paulo (USP)} and {Heidelberg University}",
title = "A new mechanism for millennial scale positive precipitation
anomalies over tropical South America",
journal = "Quaternary Science Reviews",
year = "2019",
volume = "225",
pages = "e105990",
month = "Dec.",
keywords = "Quaternary, Paleoclimatology, South America, Inorganic
geochemistry, Heinrich Stadials, Precipitation,
X-rayfluorescence.",
abstract = "Continental and marine paleoclimate archives from northwestern and
northeastern South America recorded positive precipitation
anomalies during Heinrich Stadials (HS). These anomalies have been
classically attributed to enhanced austral summer (monsoon)
precipitation. However, the lack of marine paleoclimate records
off eastern South America as well as inconsistencies between
southeastern South American continental and marine records hamper
a comprehensive understanding of the mechanism responsible for
(sub-) tropical South American hydroclimate response to HS. Here
we investigate piston core M125-95-3 collected off eastern South
America (10.94°S) and simulate South American HS conditions with a
high-resolution version of an atmosphere-ocean general circulation
model. Further, meridional changes in precipitation over (sub-)
tropical South America were assessed with a thorough compilation
of previously available marine paleorecords. Our ln(Ti/Ca) and
ln(Fe/K) data show increases during HS6-Younger Dryas. It is the
first core off eastern South America and the southernmost from the
Atlantic continental margin of South America that unequivocally
records HS-related positive precipitation anomalies. Based on our
new data, model results and the compilation of available marine
records, we propose a new mechanism for the positive precipitation
anomalies over tropical South America during HS. The new mechanism
involves austral summer precipitation increases only over eastern
South America while the rest of tropical South America experienced
precipitation increases during the winter, challenging the widely
held assumption of a strengthened monsoon. South American
precipitation changes were triggered by dynamic and thermodynamic
processes including a stronger moisture supply from the equatorial
North Atlantic (tropical South Atlantic) in austral winter
(summer).",
doi = "10.1016/j.quascirev.2019.105990",
url = "http://dx.doi.org/10.1016/j.quascirev.2019.105990",
issn = "0277-3791",
language = "en",
targetfile = "campos_new.pdf",
urlaccessdate = "01 jun. 2024"
}