Paleoclimatology, the study of earth's past climate, is essential to our understanding of current climate and predicting what our future climate will look like. Since modern data fails to show what Earth’s climate was like long ago, scientists turn to natural climate proxies such as tree rings, ice cores, lake cores, etc., which provide data from hundreds to millions of years ago. Speleothems from tropical South America present us with the opportunity to extend paleoclimate records and uncover responses of low latitude to high latitude climate forcings. The variability in the South American Summer Monsoon (SASM) is recorded in the δ18Ocalcite and δ13Ccalcite of speleothems, with the current record extending through the penultimate glacial period. I studied stalagmite 22-7, collected from Huagapo Cave in the Upper Amazon Basin of the Peruvian Andes Mountains, to identify variation of the SASM. My findings suggest a 10,000 year long hiatus in result of prior calcite precipitation, which happens when calcite precipitates from infiltrating the epikarst, giving heavier values when the water drips down, not reflecting what is truly going on at the surface. This period spans from MIS 8 to the beginning of MIS 9 and points to drier conditions, while there is also a shift to lighter rain before the hiatus at 291,000 year BP, signifying a less intense SASM.
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