Recent burning of boreal forests exceeds fire regime limits of the past 10,000 years

noaa-fire-15775 Kelly fire data from Windy Lake, Yukon Flats, Alaska - IMPD USWIL008 Kelly, R.F.; Chipman, M.L.; Higuera, P.E.; Stefanova, I.; Brubaker, L.B.; Hu, F.S. Kelly fire data from Windy Lake, Yukon Flats, Alaska - IMPD USWIL008 2013-07-06 NCDC-Paleoclimatology ONLINE Files Pending https://www.ncdc.noaa.gov/paleo/study/15775 Investigator R.F. Kelly Investigator M.L. Chipman Investigator P.E. Higuera Investigator I. Stefanova Investigator L.B. Brubaker Investigator F.S. Hu earth science paleoclimate fire history|paleolimnology depth at sample start,null,null,centimeter,null,fire history|paleolimnology,null,null,N,null earth science paleoclimate fire history|paleolimnology depth at sample end,null,null,centimeter,null,fire history|paleolimnology,null,null,N,null earth science paleoclimate fire history|paleolimnology magnetic susceptibility,sediment,null,dimensionless (CGS system),null,fire history|paleolimnology,null,null,N,1e-6 unitless CGS earth science paleoclimate fire history|paleolimnology charcoal,sediment,null,count,null,fire history|paleolimnology,null,null,N,> 180 um earth science paleoclimate fire history|paleolimnology age at sample end,null,null,calendar year before present,null,fire history|paleolimnology,null,null,N,null earth science paleoclimate fire history|paleolimnology age at sample start,null,null,calendar year before present,null,fire history|paleolimnology,null,null,N,null earth science paleoclimate fire history|paleolimnology volume,wet sediment,null,milliliter,null,fire history|paleolimnology,null,null,N,null earth science paleoclimate fire history charcoal sediment geoscientificInformation Arctic Medieval Climate Anomaly (MCA) 2808 cal yr BP -58 cal yr BP Complete 66.04169 66.04169 -145.75471 -145.75471 245 245 Continent North America United States Of America Alaska Windy Lake>LATITUDE 66.04169>LONGITUDE -145.75471 None Please cite original publication, online resource, dataset and publication DOIs (where available), and date accessed when using downloaded data. If there is no publication information, please cite investigator, title, online resource, and date accessed. The appearance of external links associated with a dataset does not constitute endorsement by the Department of Commerce/National Oceanic and Atmospheric Administration of external Web sites or the information, products or services contained therein. For other than authorized activities, the Department of Commerce/NOAA does not exercise any editorial control over the information you may find at these locations. These links are provided consistent with the stated purpose of this Department of Commerce/NOAA Web site. English DOC/NOAA/NESDIS/NCEI National Centers for Environmental Information, NESDIS, NOAA, U.S. Department of Commerce https://www.ncdc.noaa.gov/data-access/paleoclimatology-data DATA Center Contact Bruce Bauer bruce.a.bauer@noaa.gov paleo@noaa.gov 303-497-6280 303-497-6513

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Boulder CO 80305-3328 USA online ASCII Ryan Kelly, Melissa L. Chipman, Philip E. Higuera, Ivanka Stefanova, Linda B. Brubaker, and Feng Sheng Hua 2013 Recent burning of boreal forests exceeds fire regime limits of the past 10,000 years Proceedings of the National Academy of Sciences 32 110 13055–13060 www.pnas.org/cgi/doi/10.1073/pnas.1305069110

Wildfire activity in boreal forests is anticipated to increase dramatically, with far-reaching ecological and socioeconomic consequences. Paleorecords are indispensible for elucidating boreal fire regime dynamics under changing climate, because fire return intervals and successional cycles in these ecosystems occur over decadal to centennial timescales. We present charcoal records from 14 lakes in the Yukon Flats of interior Alaska, one of the most flammable ecoregions of the boreal forest biome, to infer causes and consequences of fire regime change over the past 10,000 y. Strong correspondence between charcoal-inferred and observational fire records shows the fidelity of sedimentary charcoal records as archives of past fire regimes. Fire frequency and area burned increased ~6,000–3,000 y ago, probably as a result of elevated landscape flammability associated with increased Picea mariana in the regional vegetation. During the Medieval Climate Anomaly (MCA; ~1,000–500 cal B.P.), the period most similar to recent decades, warm and dry climatic conditions resulted in peak biomass burning, but severe fires favored less-flammable deciduous vegetation, such that fire frequency remained relatively stationary. These results suggest that boreal forests can sustain high severity fire regimes for centuries under warm and dry conditions, with vegetation feedbacks modulating climate–fire linkages. The apparent limit to MCA burning has been surpassed by the regional fire regime of recent decades, which is characterized by exceptionally high fire frequency and biomass burning. This extreme combination suggests a transition to a unique regime of unprecedented fire activity. However, vegetation dynamics similar to feedbacks that occurred during the MCA may stabilize the fire regime, despite additional warming. STUDY NOTES: Chronology and macroscopic charcoal counts (number of pieces >180 microns) from Windy Lake sediments Yukon Flats, Alaska; Entity name, WI08 (Internal lab code); Contact person, Kelly R.; Sampling date, 2008-07-08; Sampling device, All cores were taken with a combination of 7.5 cm livingstone, 5 cm livingstone, and 7.5 cm polycarbonate tube; Water depth(cm), 1160; Sample storage, All cores have archive halves intact, and working halves sliced at 0.25-cm resolution. These are kept at 4°C in the Hu Lab, University of Illinois, Urbana.; Analysis method, Macroscopic charcoal counts. Please see Kelly et al. 2013 for details; Location Description, Yukon Flats Alaska;

GET DATA https://www1.ncdc.noaa.gov/pub/data/paleo/firehistory/charcoal/northamerica/uswil008-kelly2013.txt GET DATA https://www1.ncdc.noaa.gov/pub/data/paleo/firehistory/charcoal/northamerica/kelly-et-al-2013-for-noaa.xlsx GET DATA https://www1.ncdc.noaa.gov/pub/data/paleo/firehistory/charcoal/northamerica/uswil008.mag GET DATA https://www1.ncdc.noaa.gov/pub/data/paleo/firehistory/charcoal/northamerica/uswil008-kelly2013-mag.txt GET DATA https://www1.ncdc.noaa.gov/pub/data/paleo/firehistory/charcoal/northamerica/uswil008.txt USA/NOAA DIF Version 9.8.4 2018-12-11 2018-12-11