A Novel Post-1950 Ad Atmospheric 14c Record for the Tropics Using Absolutely Dated Tree Rings in the Equatorial Amazon

• DOI: 10.2139/ssrn.4646320
• Publication Date: 2023-11-28T03:53:38Z
• Authors: Guaciara M. Santos; Daniela Granato-S...; Santiago Ancapichún; Rose Oelkers; Heather A. Haines; Ricardo De Pol-Holz; Laia Andreu-Hayles; Quan Hua; Ana Carolina Barbosa
• Keywords: Tree (set theory)

In this study, we present a comprehensive atmospheric 14C record spanning from 1940 to 2016, derived 77 single tree rings of Cedrela odorata located in the Eastern Amazon Basin (EAB). This record, comprising 175 high-precision radiocarbon measurements obtained through accelerator mass spectrometry (AMS), offers detailed chronology post-1950 A.D. fluctuations Tropical Low-Pressure Belt (TLPB). To ensure accuracy and reliability, included 14C-AMS results successive cuts 1962 1963 conducted interlaboratory comparisons. addition, concentrations single-yr also allowed verify tissue growth seasonality. The strategic location tree, just above River estuary areas, prevented influence local fossil-CO2 emissions mining trade activities Central on record. Our findings reveal notable increase land-respired CO2 starting 1970s, decade earlier than previously predicted, followed by slight decrease after 2000, signaling transition towards fossil fuel era. shift is likely attributed changes reservoir sources or global dynamics. EAB when compared with shorter Muna Island, Indonesia, highlights regional differences contributes more nuanced understanding variations at low latitudes. study not only fills critical spatial gaps existing compilations but aids refining demarcation over South America. extended tree-ring pivotal for reevaluating patterns, particularly context current carbon budget, underscores importance tropical regions carbon-climate feedbacks.