TY - JOUR
T1 - Late Miocene-early Pliocene hydroclimate evolution of the western Altiplano, northern Chile
T2 - Implications for aridification trends under warming climate conditions
AU - Mentzer, Carlie
AU - Garzione, Carmala
AU - Jaramillo, Carlos
AU - Hinojosa, Luis Felipe
AU - Escobar, Jaime
AU - Glade, Nataly
AU - Gomez, Sebastian
AU - Upadhyay, Deepshikha
AU - Tripati, Aradhna
AU - Thirumalai, Kaustubh
N1 - Publisher Copyright:
© 2024 The Authors
PY - 2025/2
Y1 - 2025/2
N2 - The Miocene-Pliocene boundary (∼5.3 million years ago, Ma) represents a climate transition, where global warming resulted in a rise in sea surface temperatures from near modern values in the late Miocene, to sustained, warmer than modern values in the early Pliocene. Estimated atmospheric CO2 concentrations were within the range of anthropogenic values. Thus, this transition provides an opportunity to evaluate hydroclimate responses to warming, when the Earth system was in equilibrium with near modern atmospheric CO2 levels. Here, we utilize lacustrine carbonate stable and clumped isotope methods, and palynology, to investigate hydroclimate trends within the western Altiplano of Chile during the late Miocene and early Pliocene. The results provide observational support for a warmer and wetter-than-modern climate over these timeframes. However, increasing aridity across the Miocene-Pliocene boundary suggests a hydroclimate response to global climate forcing. Given the sensitivity of the region's climate to disturbances in tropical Pacific, ocean-atmospheric processes, we speculate that this aridification may reflect progressive weakening of the Pacific Walker Circulation, in response to global warming.
AB - The Miocene-Pliocene boundary (∼5.3 million years ago, Ma) represents a climate transition, where global warming resulted in a rise in sea surface temperatures from near modern values in the late Miocene, to sustained, warmer than modern values in the early Pliocene. Estimated atmospheric CO2 concentrations were within the range of anthropogenic values. Thus, this transition provides an opportunity to evaluate hydroclimate responses to warming, when the Earth system was in equilibrium with near modern atmospheric CO2 levels. Here, we utilize lacustrine carbonate stable and clumped isotope methods, and palynology, to investigate hydroclimate trends within the western Altiplano of Chile during the late Miocene and early Pliocene. The results provide observational support for a warmer and wetter-than-modern climate over these timeframes. However, increasing aridity across the Miocene-Pliocene boundary suggests a hydroclimate response to global climate forcing. Given the sensitivity of the region's climate to disturbances in tropical Pacific, ocean-atmospheric processes, we speculate that this aridification may reflect progressive weakening of the Pacific Walker Circulation, in response to global warming.
KW - Clumped isotopes
KW - Lake carbonate
KW - Paleoclimate
KW - Tropics
KW - Walker circulation
KW - Western Altiplano
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U2 - 10.1016/j.gloplacha.2024.104674
DO - 10.1016/j.gloplacha.2024.104674
M3 - Article
AN - SCOPUS:85211699128
SN - 0921-8181
VL - 245
JO - Global and Planetary Change
JF - Global and Planetary Change
M1 - 104674
ER -