Abstract:
This is the first glacial-interglacial fire history reconstruction using the specific biomarker levoglucosan from an Arctic ice core: the NEEM ice core. My research acknowledges the weaknesses inherent in most of previous approaches for reconstructing past fire activity, where other fire proxies were unspecific or the environmental archives did not allow high temporal-resolution and -length reconstructions. I present the first high-resolution reconstruction of fire activity over the past 120,000 years. After validating my approach, I compared my results with Northern Hemisphere fire records, climate conditions and forcings to identify sources and controls of fire emissions. Using the collected data, I tested the "Ruddiman hypothesis” of early human contribution to climate change during the Holocene and the effect of fires on the global greenhouse gas budget. Finally I offer explanations for Eemian concentrations, that are unexpectedly low for a warmer-than-present interglacial period.