Tropical oceans are the main global water vapor and latent heat sources, but their responses to radiative forcing remain unclear. Here, we investigate oceanic moisture dynamics of the western tropical Pacific (WTP) over the past 210,000 years through an approach of planktonic foraminiferal triple oxygen isotope (Δ'O). The Δ'O record is dominated by the precession cycles (~23,000 years), with lower values reflecting higher humidity in concert with higher Northern Hemisphere summer insolation.
View Article and Find Full Text PDFThe Sahara Desert, one of today's most inhospitable environments, has known periods of enhanced precipitation that supported pre-historic humans. However, the Green Sahara timing and moisture sources are not well known due to limited paleoclimate information. Here, we present a multi-proxy (δO, δC, ΔO, and trace elements) speleothem-based climate record from Northwest (NW) Africa.
View Article and Find Full Text PDFWe present a speleothem record from western Cuba, spanning the period 98.7-84.9 ka BP.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
September 2020
The Younger Dryas (YD), arguably the most widely studied millennial-scale extreme climate event, was characterized by diverse hydroclimate shifts globally and severe cooling at high northern latitudes that abruptly punctuated the warming trend from the last glacial to the present interglacial. To date, a precise understanding of its trigger, propagation, and termination remains elusive. Here, we present speleothem oxygen-isotope data that, in concert with other proxy records, allow us to quantify the timing of the YD onset and termination at an unprecedented subcentennial temporal precision across the North Atlantic, Asian Monsoon-Westerlies, and South American Monsoon regions.
View Article and Find Full Text PDFAn amendment to this paper has been published and can be accessed via a link at the top of the paper.
View Article and Find Full Text PDFThe Massa basin in Morocco suffers from water scarcity and water quality degradation largely due to salinity and nitrate contamination. In this study, a multi-tracer approach, was used that integrated water chemistry, stable isotopes of water (δO, δH) and stable isotopes of nitrate (δN, δO), to investigate mineralization and nitrate contamination in the Massa catchment. The main objective was to identify, for the first time in the area, water pollution sources, with an emphasis on nitrate-originated contamination using the δN isotope.
View Article and Find Full Text PDFHere we present a new composite record from two well-dated speleothem records from two caves in Northern Morocco. The high-resolution record covers the last millennium allowing to detect multi-decadal to centennial periodicities. Over the industrial period, δO values of our speleothems are shown to be dominated by the main mode of decadal variability in the North Atlantic region: the North Atlantic Oscillation (NAO).
View Article and Find Full Text PDFThe Plio-Quaternary aquifer of Chtouka is located in Southwestern of Morocco. The intensive agricultural activity in Chtouka basin requires the mobilization of 94% of fresh water resources for irrigation. This overexploitation, along with the succession of drought years, sea water intrusion and various sources of pollution, affected the quality and availability of groundwater resources.
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