1.5 million years of black carbon deposition from Lake Elgygytgyn, Northeast Arctic Russia

Wildfires are a crucial component of the Earth system with impacts on surface albedo, atmospheric chemistry, and terrestrial ecosystems. Understanding the linkages between past climate and fire activity is important to improve modeling of wildfires under future climate scenarios. Most paleo-fire reconstructions have focused on constraining historical fire trends across recent centuries and millennia, but little is known about how fire activity has changed on longer timescales, including across glacial-interglacial climate cycles. Here, we present a 1.5 million-year lake-sediment record of refractory black carbon (rBC) from Lake Elgygytgyn (Lake E), Northeast Arctic Russia to investigate linkages between glacial-interglacial climate and rBC deposition. rBC deposition and particle mass distributions show consistent variability over the past 1.5 Ma, with relatively higher rBC concentrations and larger particle mass distributions associated with peak glacial climates, while the warmest erasso called super-interglacialsare characterized by intermediate rBC concentrations and anomalously small particle mass distributions. Though rBC deposition at Lake E closely parallels climate, it also is closely linked to sediment facies and other Lake E chemical proxies. The strong correlation between rBC and total organic carbon suggests potential post-depositional impacts to rBC during eras of oxygenated bottom waters and enhanced organic matter decomposition.