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Abstract Recent wildfire activity in semi-arid regions like western North America exceeds the range of historical records. High-resolution paleoclimate archives such as stalagmites could illuminate the link between hydroclimate, vegetation change, and fire activity in pre-anthropogenic climate states beyond the timescale of existing tree-ring records. Here we present an analysis of levoglucosan, a combustion-sensitive anhydrosugar, and lignin oxidation products (LOPs) in a stalagmite, reconstructing fire activity and vegetation composition in the California Coast Range across the 8.2 kyr event. Elevated levoglucosan concentrations suggest increased fire activity while altered LOP compositions indicate a shift toward more woody vegetation during the event. These changes are concurrent with increased hydroclimate volatility as shown by carbon and calcium isotope proxies. Together, these records suggest that climate whiplash (oscillations between extreme wetness and aridity) and fire activity in California, both projected to increase with anthropogenic climate change, were tightly coupled during the early Holocene.
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Fire records (levoglucosan, mannosan, and galactosan) recorded in the deep Denali, AK ice core from ~360 to 2013 CE
Monosaccharide anhydrides (MAs), or anhydrosugars which include levoglucosan, mannosan, and galactosan are combustion products of cellulose and hemicellulose that are used as biomass burning tracers. These fire biomarkers are incorporated into smoke plumes, transported through the atmosphere, and return to the surface through wet and dry deposition that can be archived in ice cores. Here, we quantify levoglucosan, mannosan, and galactosan through the Denali ice core to investigate past North Pacific fire activity.
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- Award ID(s):
- 2002470
- PAR ID:
- 10653679
- Publisher / Repository:
- U.S. Geological Survey
- Date Published:
- Subject(s) / Keyword(s):
- biota fire paleoclimate Geochemistry FOS: Earth and related environmental sciences Climatology Glaciology biomass burning ice core
- Format(s):
- Medium: X Other: csv; xml
- Sponsoring Org:
- National Science Foundation
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