Collaborative Research: Paleoenvironmental Changes in the Bolivian Altiplano: A High-Resoution Pollen Record from the Sajama Ice Cap

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This project seeks to produce a high-resolution pollen record of climatic and vegetational changes during the last 25,000 years from the Sajama ice cap in the Altiplano of Bolivia. Pollen preserved in ice cores retrieved from the Sajama ice cap will be analyzed at annual to decadal sampling resolutions to detect the response of the tropical Andean vegetation to century-scale climatic fluctuations occurring during the late-Holocene, such as the Little Ice Age, the Medieval Warm Period, and the regional drought events that episodically lowered the water levels in Lake Titicaca during the last 3500 years. The pollen data will also complement other paleoclimatic proxies to shed light on the vegetational response to abrupt climatic changes occurring during the Last Glacial Maximum and deglacial times, including a deglaciation climatic reversal about 14,000 to 11,500 years ago that is correlative with the North Atlantic Younger Dryas stadial.This research will be the first systematic pollen study of a tropical ice core. It will advance the field of ice-core palynology and will enhance the use of pollen as a paleoclimatic and paleoecological proxy in ice-core research. The 25,000-year pollen record from the Sajama ice cap will add to only one other continuous pollen record from the entire tropical Andes and western Amazonia south of the equator that contains information pertaining to the vegetation and climatic conditions of the Last Glacial Maximum. It will offer a unique opportunity to study the sensitivity of the tropical Andean vegetation to past and future climatic changes.