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Natalie M. Kehrwald

Natalie Kehrwald is a Research Geologist working at the Geosciences and Environmental Change Science Center

Education

PhD, Earth Sciences, The Ohio State University, 2009

MS, Geosciences, University of Massachusetts Amherst, 2004

BA, Environmental Science/Geology, Colorado College, 1999

 

Appointments

2015 - present       Research Geologist, Geosciences and Environmental Change Science Center, USGS, Denver, Colorado 

2011 - 2015           Research Scientist, Department of Environmental Sciences, Informatics and Statistics, University of Venice, Italy  

2009 - 2011           Marie Curie Post-Doctoral Fellow, Italian National Research Council (CNR-IPDA), Italy 

2009                      Visiting Assistant Professor, Geology Department, Colorado College

1999 - 2001           U.S. Peace Corps, Environmental Engineer, Bolivia 

 

 

 

Science and Products

Filter Total Items: 16

Rapa Nui (Easter Island) Rano Raraku crater lake basin: Geochemical characterization and implications for the Ahu-Moai Period

Rano Raraku, the crater lake constrained by basaltic tuff that served as the primary quarry used to construct the moai statues on Rapa Nui (Easter Island), has experienced fluctuations in lake level over the past centuries. As one of the only freshwater sources on the island, understanding the present and past geochemical characteristics of the lake water is critical to understand if the lake coul
By
Climate Research and Development Program, Geosciences and Environmental Change Science Center

A multi-decadal geochemical record from Rano Aroi (Easter Island/Rapa Nui): Implications for the environment, climate and humans during the last two millennia

The small and remote Easter Island (Rapa Nui) has a complex and still partially unknown history of human colonization and interactions with the environment. Previous research from sedimentary archives collected in the three freshwater bodies of Rapa Nui document dramatic environmental changes over the last two millennia. Yet, the characteristics of sediments and paleoenvironmental records are chal
By
Climate Research and Development Program, Geosciences and Environmental Change Science Center

Trace and rare earth elements determination in milk whey from the Veneto region, Italy

Multi-element analyses determine the content of 17 trace elements (Al, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Sr, Cd, Cs, Ba, Pb, U) and 14 rare earth elements (La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Yb, Lu, Y) in whey samples from cow and goat milk by inductively coupled plasma mass spectrometry and inductively coupled plasma-sector field mass spectrometry. A total of 261 milk whey samples w
By
Climate Research and Development Program, Geosciences and Environmental Change Science Center

Boreal blazes: Biomass burning and vegetation types archived in the Juneau Icefield

The past decade includes some of the most extensive boreal forest fires in the historical record. Warming temperatures, changing precipitation patterns, the desiccation of thick organic soil layers, and increased ignition from lightning all contribute to a combustive combination. Smoke aerosols travel thousands of kilometers, before blanketing the surfaces on which they fall, such as the Juneau Ic
By
Water Resources, Ecosystems, Climate Research and Development Program, Land Change Science Program, Toxic Substances Hydrology, Environmental Health Program, Geosciences and Environmental Change Science Center

The Great Acceleration of fragrances and PAHs archived in an ice core from Elbrus, Caucasus

The Great Acceleration of the anthropogenic impact on the Earth system is marked by the ubiquitous distribution of anthropogenic materials throughout the global environment, including technofossils, radionuclides and the exponential increases of methane and carbon dioxide concentrations. However, personal care products as direct tracers of human domestic habits are often overlooked. Here, we prese
By
Climate Research and Development Program, Geosciences and Environmental Change Science Center

Dissolved organic matter in the deep TALDICE ice core: A nano-UPLC-nano-ESI-HRMS method

Trace organic compounds in deep ice cores supply important paleoclimatic information. Untargeted analyses of dissolved organic matter provide an overview of molecular species in ice samples however, sample volumes usually required for these analyses are generally not available from deep ice cores. Here, we developed an analytical method using a nano-UPLC-nano-ESI-HRMS to detect major molecular spe
By
Climate Research and Development Program, Geosciences and Environmental Change Science Center

PaCTS 1.0: A crowdsourced reporting standard for paleoclimate data

The progress of science is tied to the standardization of measurements, instruments, and data. This is especially true in the Big Data age, where analyzing large data volumes critically hinges on that data being standardized. Accordingly, the lack of community-sanctioned data standards in paleoclimatology has largely precluded the benefits of Big Data advances in the field. Building upon recent ef
By
Climate Research and Development Program, Land Change Science Program, Geosciences and Environmental Change Science Center

Fire, vegetation, and Holocene climate in a southeastern Tibetan lake: a multi-biomarker reconstruction from Paru Co

The fire history of the Tibetan Plateau over centennial to millennial timescales is not well known. Recent ice core studies reconstruct fire history over the past few decades but do not extend through the Holocene. Lacustrine sedimentary cores, however, can provide continuous records of local environmental change on millennial scales during the Holocene through the accumulation and preservation of
By
Climate Research and Development Program, Geosciences and Environmental Change Science Center

Global Modern Charcoal Dataset (GMCD): A tool for exploring proxy-fire linkages and spatial patterns of biomass burning

Progresses in reconstructing Earth's history of biomass burning has motivated the development of a modern charcoal dataset covering the last decades through a community-based initiative called the Global Modern Charcoal Dataset (GMCD). As the frequency, intensity and spatial scale of fires are predicted to increase regionally and globally in conjunction with changing climate, anthropogenic activit
By
Climate Research and Development Program, Groundwater and Streamflow Information Program, Geosciences and Environmental Change Science Center

Lake sediment fecal and biomass burning biomarkers provide direct evidence for prehistoric human-lit fires in New Zealand

Deforestation associated with the initial settlement of New Zealand is a dramatic example of how humans can alter landscapes through fire. However, evidence linking early human presence and land-cover change is inferential in most continental sites. We employed a multi-proxy approach to reconstruct anthropogenic land use in New Zealand’s South Island over the last millennium using fecal and plant
By
Climate Research and Development Program, Groundwater and Streamflow Information Program, Land Change Science Program, Geosciences and Environmental Change Science Center

High latitude Southern Hemisphere fire history during the mid-late Holocene (750- 6000 yr BP)

We determined the specific biomass burning biomarker levoglucosan in an ice core from the TALos Dome Ice CorE drilling project (TALDICE) during the mid- to late Holocene (6000–750 BP). The levoglucosan record is characterized by a long-term increase with higher rates starting at  ∼  4000 BP and peaks between 2500 and 1500 BP. The anomalous increase in levoglucosan centered at  ∼  2000 BP is consis
By
Climate Research and Development Program, Groundwater and Streamflow Information Program, Geosciences and Environmental Change Science Center

A North American Hydroclimate Synthesis (NAHS) of the Common Era

This study presents a synthesis of century-scale hydroclimate variations in North America for the Common Era (last 2000 years) using new age models of previously published multiple proxy-based paleoclimate data. This North American Hydroclimate Synthesis (NAHS) examines regional hydroclimate patterns and related environmental indicators, including vegetation, lake water elevation, stream flow and
By
Water Resources, Climate Research and Development Program, Energy Resources Program, Groundwater and Streamflow Information Program, Mineral Resources Program, National Laboratories Program, Science and Decisions Center, Florence Bascom Geoscience Center, Geology, Minerals, Energy, and Geophysics Science Center, Geosciences and Environmental Change Science Center, St. Petersburg Coastal and Marine Science Center

Non-USGS Publications**

Van Marle, M.J.E.; Kloster, Silvia; Magi, B.I.; Marlon, J.R.; Daniau, Anne-Laure; Field, R.D.; Arneth, Almut; Forrest, Matthew; Hantson, Stijn; Kehrwald, N.M.; Knorr, Wolfgang; Lasslop, Gitta; Li, Fang; Mangeon, Stéphane; Yue, Chao; Kaiser, J.W.; and van der Werf, G.R., 2017, Historic global biomass burning emissions for CMIP6 (BB4CMIP) based on merging satellite observations with proxies and fire models (1750-2015): Geoscientific Model Development, v. 10, iss. 9.
Battistel, D., Argiriadis, E., Kehrwald, N., Spigariol, M., Russell, J.M., Barbante, C., 2017, Fire and human record at Lake Victoria, East Africa during the Early Iron Age: Did humans or climate cause massive ecosystem changes?: The Holocene, DOI: 10.1177/0959683616678466
Gabrielli, P., Barbante, C., Bertagna, G., Merto, M., Binder, D., Carton, A., Carturan, L., Cazorzi, F., Cozzi, C., Dalla Dontana, G., Davis, M., De Blasi, F., Dinale, R., Draga, G., Dreossi, G., Festi, D., Frezzotti, M., Gabrieli, J., Galos, S.P., Ginot, P., Heidenwolf, P., Jenk, T.M., Kehrwald, N.M., Kenny, D., Magand, O., Mair, V., Mikhalenko, C., Lin, P.N., Oeggl, K., Piffer, G., Rinaldi, M., Schotterer, U., Schwikowski, M., Seppi, R., Spolaor, A., Stenni, B., Tonidandel, D., Uglietti, C., Zagorodnov, V., Zanoner, T., Sennaro, P., 2016, Age of the Mt. Ortles ice cores, the Tyrolean Iceman and glaciation of the highest summit of South Tyrol since the Northern Hemisphere Climatic Optimum: Cryosphere, 10, 6, 2779-2797, DOI:10.5194/tc-10-2779-2016
Brovkin, V, Brücher, T., Kleinen, T., Zaehle, S., Joos, F., Roth, R., Spahni, R., Schmitt, J., Fischer, H., Leuenberger, M., Stone, E., Ridgewell, A., Chappellaz, J., Kehrwald, N., Barbante, C., Blunier, T., Dahl Jensen, D., 2016, Comparative carbon cycle dynamics of past and present interglacials: Quaternary Science Reviews, 137, 15-32, DOI/10.1016/j.quascirev.2016.01.028
Zangrando, R., Barbaro, E., Vecchiato, M., Kehrwald, N., Barbante, C., Gambaro, A., 2016, Levoglucosan and phenols in marine, coastal and inland Antarctic aerosols: Science of the Total Environment, 544, 606-616, doi:10.1016/j.scitotenv.2015.11.166
Zennaro, P., N. Kehrwald, J. Marlon, W. F. Ruddiman, T. Brücher, C. Agostinelli, D. Dahl-Jensen, R. Zangrando, A. Gambaro, and C. Barbante, 2015, Europe on fire three thousand years ago: Arson or climate?: Geophys. Res. Lett., 42, 5023–2033. doi: 10.1002/2015GL064259.
Schüpbach, S., Kirchgeorg, T., Colombaroli, D., Beffa, G., Radaelli, M., Kehrwald, N., Barbante, C., 2015, Combining charcoal sediment and molecular markers to infer a Holocene fire history in the Maya lowlands of Petén, Guatemala: Quaternary Science Reviews 05/2015; 115. DOI:10.1016/j.quascirev.2015.03.004
Portenga, E.W., Bierman, P.R., Duncan, C., Corbett, L.B., Kehrwald, N.M., Rood, D.H., 2015, Erosion rates of the Bhutanese Himalaya determined using in situ-produced 10Be: Geomorphology, 233, 122-126 doi:0.1016/j.geomorph.2014.09.027
Kehrwald, N., Zennaro, P., Schüpbach, S., Kirchgeorg, T., McConnell, J.R., Zangrando, R., Gambaro, A., Barbante, C., 2015, Two thousand years of boreal biomass burning recorded in the NEEM ice cores: PAGES Magazine Vol. 23, 1, 14-15
Wang, N., Xiaobo, W., Kehrwald, N., Li, Z., Li, Q., Jiang, X., Pu, J., 2015, Fukushima Nuclear Accident Recorded in Tibetan Plateau Snow Pits: PloS ONE, 10 (2) e0116580
Gabrielli, P, Hardy, D.R., Kehrwald, N., Davis, M., Cozzi, G., Turetta, C., Barbante, C., Thompson, L.G., 2014, Deglaciated areas of Kilimanjaro as a source of volcanic trace elements deposited on the ice cap during the late Holocene: Quaternary Science Reviews, 93, 1-10, DOI:10.1016/j.quascirev.2014.03.007
Guo, Z., Wang, N., Kehrwald, N.M., Mao, R., Wu, H., Wu, Y., Jiang, X., 2014, Temporal and spatial changes in Western Himalayan firn line altitudes from 1998 to 2009: Global and Planetary Change, 118, 97-105. DOI: 10.1016/j.gloplacha.2014.03.012
Kirchgeorg, T., Schüpbach, S. Kehrwald, N., McWethy, D., Barbante, C., 2014, Method for determining levoglucosan, mannosan and galactosan in sediment to reconstruct past fire activity: Organic Geochemistry, 71, 1-6, DOI:10.1016/j.orggeochem.2014.02.014
Zennaro, P., Kehrwald, N., McConnell, J., Schüpbach, S, Masselli, O., Marlon, J., Zangrando, R., Vallelonga, P., Spolaor, A., Varin, C., Borrotti, M., Gambaro, A., Barbante, B., 2014, Fire in ice: two millennia of Northern Hemisphere fire history from the Greenland NEEM ice core: Climate of the Past, 10, 1905–1924, 2014 www.clim-past.net/10/1905/2014/ doi:10.5194/cp-10-1905-2014
Kehrwald, N., Whitlock, C., Barbante, C., Brovkin, V., Daniau, A-L-. Kaplan, J.O., Marlon, J.R., Power, M.J., Thomicke, K., Van der Werf, G., 2013, Fire Research: Linking Past, Present and Future Data: EOS, Vol. 94, No. 46, 12 November 2013, DOI: 10.1002/2013EO460001
Barbante, C., Kehrwald, N., Marianelli, P., Vinther, B. M.,Cozzi, G., Hammer, C., Clausen, H., Siggard Andersen, M., 2013, Greenland ice core evidence of the 79 AD Vesuvius eruption: Climate of the Past, 9, 1221–1232, 2013 www.clim-past.net/9/1221/2013/ doi:10.5194/cp-9-1221-2013
Spolaor, A., Vallelonga, P., Plane, J.M.C, Kehrwald N., Gabrieli J., Varin C., Turetta C., Cozzi G., Boutron C. and Barbante C., 2013, Halogen species record Antarctic sea ice over glacial-interglacial periods: Atmospheric Chemistry and Physics, 13, 6623–6635, 2013 www.atmos-chem-phys.net/13/6623/2013/ doi:10.5194/acp-13-6623-2013
Spolaor A., Vallelonga P., Gabrieli J., Kehrwald N., Turetta C., Cozzi G., Poto L., Plane J.M.C., Boutron C.F., Barbante C., 2013, Speciation analysis of iodine and bromine at picogram-per-gram levels in polar ice: Analytical and Bioanalytical Chemistry, DOI: 10.1007/s00216-012-5806-0
Zangrando, R., Barbaro, E., Zennaro, P., Rossi, S., Kehrwald, N.M., Gabrieli, J., Barbante, C., Gambaro, A., 2013, Biomass burning molecular markers in Arctic aerosols: Environmental Science and Technology, 47, 8565−8574, dx.doi.org/10.1021/es400125r
Kirchgeorg, T., Dreyer, A., Gabrieli, J., Kehrwald, N., Sigl, M., Schwikowski, M., Boutron, C., Gambaro, A., Barbante, C., Ebinghaus, R., 2013, Temporal Variations of Perfluoroalkyl Substances and Polybromintad Diphenyl Ethers in Alpine Snow: Environmental Pollution 178, 367-374.
Spolaor, A., Vallelonga, P., Cozzi, G., Gabrieli, J., Varin, C., Kehrwald, N., Zennaro, P., Boutron, C., Barbante, C., 2013, Iron speciation influences iron bioavailability over glacial-interglacial cycles: Geophysical Research Letters, 40, 8, 618–1623, DOI: 10.1002/grl.50296
Poto, L., Gabrieli, J., Crowhurst, S., Appleby, P.G., Ferretti, P., Zaccone, C., Surian, N., Ferretti, P., Cozzi, G., Turetta, C., Kehrwald, N.M., Barbante, C., 2013, The first continuous last Late Glacial - Holocene peat bog record from the Dolomites (NE Italian Alps): Quaternary International, http://dx.doi.org/10.1016/j.quaint.2013.05.001
Kehrwald, N., P. Zennaro, Barbante, C., 2013, Biomass burning records over the present and past interglacial periods: PAGES News, 21, 1
Kehrwald, N., Zangrando, R., Gabrielli, P., Barbante, C., Gambaro, A., 2012, Levoglucosan as a specific marker of fire events in Greenland snow: Tellus B, 64, May. 2012. Available at: http://www.tellusb.net/index.php/tellusb/article/view/18196
Scalabrin, E., Zangrando, R., Barbaro, E., Kehrwald, N, Gabrieli, J., Barbante, C., Gambaro, A., 2012, Amino acids in Arctic aerosols: Atmospheric Chemistry and Physics 12, 10453-10463, doi:10.5194/acp-12-10453-2012
Gabrielli, P., Barbante, C., Carturan, L., Cozzi, G., Dalla Fontana, G., Dinale, R., Draga, G., Gabrieli, J., Kehrwald, N., Mair, V., Mikhalenko, G., Seppi, R., Spolaor, A., Thompson, L.G., Tonidandel, D., 2012, Discovery of cold ice in a deep drilling site in the Eastern European Alps: Geografia Fisica e Dinamica Quaternaria, 35, 101-105, Doi: 10.4461/GFDQ.2012.35.10
Gabrieli, J., Carturan, L., Gabrielli, P., Kehrwald, N., Turetta, C., Cozzi, G., Spolaor, A., Dinale, R., Staffler, H., Seppi, R., Dalla Fontana, G., Thompson, L.G., Barbante, C., 2011, Impact of Po Valley emissions on the highest glacier of the Eastern European Alps: Atmospheric Chemistry and Physcis, 11, 15, 80-87-8102, Doi:10.5194/acp-11-8087-2011
Kehrwald, N., McCoy, W., Thibeault, J., Burns, S., Oches, E., 2010, Paleoclimatic implications of modern and LGM European land-snail shell δ18O: Quaternary Research 74, 1, 167-177.
Kehrwald, N., Zangrando, R., Gambaro, A., Barbante, C., 2010, Fire and climate: Biomass burning recorded in ice and lake cores: European Physical Journal, 9, 105-114, Doi: 10.1051/epjconf/201009008
Kehrwald, N., Zangrando, R., Gambaro, A., Cescon, P., Barbante, C., 2010, Specific molecular markers in ice cores provide large-scale patters in biomass burning: PAGES News, 18, 2
Fortner, S., Fountain, A., Lyons, W., Welch, K., Kehrwald, N., 2009, Trace element and major ion concentrations and dynamics in glacier snow and melt: Eliot Glacier, Oregon Cascades: Hydrological Processes, 23, 2987-2996.
Kehrwald, N.M., Thompson, L.G., Yao, T., Mosley-Thompson, E., Schotterer, U., Alfimov, V., Beer, J., Eikenberg, J., Davis, M.E., 2008, Mass loss on Himalayan glacier endangers water resources: Geophysical Reserch Letters, 35, L22503, doi:10.1029/2008GL035556
Gardner, T., Marshall, J., Merritts, D., Bee, B., Burgette, R., Burton, E., Cooke, J.,Kehrwald, N., Protti, M., Fisher, D., Sak, P., 2001, Holocene forearc block rotation in response to seamount subduction, southeastern Peninsula, Costa Rica: Geology, 29, 2, 151-154.

**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.

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Coring on the Juneau Icefield

Fire and vegetation changes recorded in Alaskan ice cores

The past decade has comprised major fires in central Alaska and Siberia. Fire histories from ice cores in the North Pacific (Denali and the Juneau Icefield) record interactions between changing temperature, precipitation, and biomass burning. We aim to quantify what vegetation burned in the past (hardwoods versus softwoods versus grasses) using ratios of levoglucosan, mannosan and galactosan, and...
By
Geosciences and Environmental Change Science Center
link

Fire and vegetation changes recorded in Alaskan ice cores

The past decade has comprised major fires in central Alaska and Siberia. Fire histories from ice cores in the North Pacific (Denali and the Juneau Icefield) record interactions between changing temperature, precipitation, and biomass burning. We aim to quantify what vegetation burned in the past (hardwoods versus softwoods versus grasses) using ratios of levoglucosan, mannosan and galactosan, and...
Learn More
link
Doing USGS fieldwork at Bear Lake, CO showing location, raft, and personnel

Fire, human activity, and climate records in southwestern US sediments

This research aims to determine if climate change or human activity was the primary driver of fire activity in southwestern Colorado.
By
Geosciences and Environmental Change Science Center
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Fire, human activity, and climate records in southwestern US sediments

This research aims to determine if climate change or human activity was the primary driver of fire activity in southwestern Colorado.
Learn More
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Bear Lake, Colorado

Did we start the fire? Climate, Fire and Humans

The past decade encompasses some of the most extensive fire activity in recorded history. An area the size of Vermont (~24,000 km2) burned in a single Siberian fire in the summer of 2019 (Kehrwald et al., 2020 and references therein) while Australia, Indonesia and the Amazon have all experienced their most intense fires in recorded history (van Wees et al, 2021 and references therein). As more...
By
Climate Research and Development Program, Geosciences and Environmental Change Science Center
link

Did we start the fire? Climate, Fire and Humans

The past decade encompasses some of the most extensive fire activity in recorded history. An area the size of Vermont (~24,000 km2) burned in a single Siberian fire in the summer of 2019 (Kehrwald et al., 2020 and references therein) while Australia, Indonesia and the Amazon have all experienced their most intense fires in recorded history (van Wees et al, 2021 and references therein). As more...
Learn More
link
Drilling firn cores on the Juneau Icefield, Alaska

Terrestrial Records of Holocene Climate Change: Fire, climate and humans

Large wildfires have raged across the western Americas in the past decade including the Las Conchas, New Mexico fire that burned 44,000 acres in a single day in 2011 (Orem and Pelletier, 2015, Geomorphology 232: 224-238, and references therein), the 2016 Fort McMurray, Alberta fire that required evacuating an entire city, and the 2015 Alaskan fire season that burned more than 5 million acres...
By
Climate Research and Development Program, Geosciences and Environmental Change Science Center
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Terrestrial Records of Holocene Climate Change: Fire, climate and humans

Large wildfires have raged across the western Americas in the past decade including the Las Conchas, New Mexico fire that burned 44,000 acres in a single day in 2011 (Orem and Pelletier, 2015, Geomorphology 232: 224-238, and references therein), the 2016 Fort McMurray, Alberta fire that required evacuating an entire city, and the 2015 Alaskan fire season that burned more than 5 million acres...
Learn More

Investigating fire frequency and vegetative combustion sources using wildland fire tracer molecules archived in the Juneau Icefield of Alaska

The past decade includes some of the most extensive boreal forest fires in the historical record. Environmental drivers include warming temperatures, changing precipitation patterns, desiccation of thick organic soil layers, and increased ignition frequency from lightning. Wildland fires produce smoke aerosols that can travel thousands of kilometers, before blanketing the surfaces on which they fa
By
Water Resources, Climate Research and Development Program, Geosciences and Environmental Change Science Center
link

Friday's Findings - January 8 2020

We Did Start the Fire: Humans, Climate and Fire in the Holocene

Date: January 8, 2021 from 2-2:30 p.m. eastern time

Speaker: Natalie Kehrwald, Research...

Read Article
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Fire Aerosols Affect Southeastern Alaskan Glaciers

This article is part of the Fall 2020 issue of the Earth Science Matters Newsletter.

Read Article
Coring on the Juneau Icefield
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Crevices on glacier, Juneau Icefield
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Glacier, Juneau Icefield
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Science and Products

  • Publications
    Filter Total Items: 16

    Rapa Nui (Easter Island) Rano Raraku crater lake basin: Geochemical characterization and implications for the Ahu-Moai Period

    Rano Raraku, the crater lake constrained by basaltic tuff that served as the primary quarry used to construct the moai statues on Rapa Nui (Easter Island), has experienced fluctuations in lake level over the past centuries. As one of the only freshwater sources on the island, understanding the present and past geochemical characteristics of the lake water is critical to understand if the lake coul
    By
    Climate Research and Development Program, Geosciences and Environmental Change Science Center

    A multi-decadal geochemical record from Rano Aroi (Easter Island/Rapa Nui): Implications for the environment, climate and humans during the last two millennia

    The small and remote Easter Island (Rapa Nui) has a complex and still partially unknown history of human colonization and interactions with the environment. Previous research from sedimentary archives collected in the three freshwater bodies of Rapa Nui document dramatic environmental changes over the last two millennia. Yet, the characteristics of sediments and paleoenvironmental records are chal
    By
    Climate Research and Development Program, Geosciences and Environmental Change Science Center

    Trace and rare earth elements determination in milk whey from the Veneto region, Italy

    Multi-element analyses determine the content of 17 trace elements (Al, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Sr, Cd, Cs, Ba, Pb, U) and 14 rare earth elements (La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Yb, Lu, Y) in whey samples from cow and goat milk by inductively coupled plasma mass spectrometry and inductively coupled plasma-sector field mass spectrometry. A total of 261 milk whey samples w
    By
    Climate Research and Development Program, Geosciences and Environmental Change Science Center

    Boreal blazes: Biomass burning and vegetation types archived in the Juneau Icefield

    The past decade includes some of the most extensive boreal forest fires in the historical record. Warming temperatures, changing precipitation patterns, the desiccation of thick organic soil layers, and increased ignition from lightning all contribute to a combustive combination. Smoke aerosols travel thousands of kilometers, before blanketing the surfaces on which they fall, such as the Juneau Ic
    By
    Water Resources, Ecosystems, Climate Research and Development Program, Land Change Science Program, Toxic Substances Hydrology, Environmental Health Program, Geosciences and Environmental Change Science Center

    The Great Acceleration of fragrances and PAHs archived in an ice core from Elbrus, Caucasus

    The Great Acceleration of the anthropogenic impact on the Earth system is marked by the ubiquitous distribution of anthropogenic materials throughout the global environment, including technofossils, radionuclides and the exponential increases of methane and carbon dioxide concentrations. However, personal care products as direct tracers of human domestic habits are often overlooked. Here, we prese
    By
    Climate Research and Development Program, Geosciences and Environmental Change Science Center

    Dissolved organic matter in the deep TALDICE ice core: A nano-UPLC-nano-ESI-HRMS method

    Trace organic compounds in deep ice cores supply important paleoclimatic information. Untargeted analyses of dissolved organic matter provide an overview of molecular species in ice samples however, sample volumes usually required for these analyses are generally not available from deep ice cores. Here, we developed an analytical method using a nano-UPLC-nano-ESI-HRMS to detect major molecular spe
    By
    Climate Research and Development Program, Geosciences and Environmental Change Science Center

    PaCTS 1.0: A crowdsourced reporting standard for paleoclimate data

    The progress of science is tied to the standardization of measurements, instruments, and data. This is especially true in the Big Data age, where analyzing large data volumes critically hinges on that data being standardized. Accordingly, the lack of community-sanctioned data standards in paleoclimatology has largely precluded the benefits of Big Data advances in the field. Building upon recent ef
    By
    Climate Research and Development Program, Land Change Science Program, Geosciences and Environmental Change Science Center

    Fire, vegetation, and Holocene climate in a southeastern Tibetan lake: a multi-biomarker reconstruction from Paru Co

    The fire history of the Tibetan Plateau over centennial to millennial timescales is not well known. Recent ice core studies reconstruct fire history over the past few decades but do not extend through the Holocene. Lacustrine sedimentary cores, however, can provide continuous records of local environmental change on millennial scales during the Holocene through the accumulation and preservation of
    By
    Climate Research and Development Program, Geosciences and Environmental Change Science Center

    Global Modern Charcoal Dataset (GMCD): A tool for exploring proxy-fire linkages and spatial patterns of biomass burning

    Progresses in reconstructing Earth's history of biomass burning has motivated the development of a modern charcoal dataset covering the last decades through a community-based initiative called the Global Modern Charcoal Dataset (GMCD). As the frequency, intensity and spatial scale of fires are predicted to increase regionally and globally in conjunction with changing climate, anthropogenic activit
    By
    Climate Research and Development Program, Groundwater and Streamflow Information Program, Geosciences and Environmental Change Science Center

    Lake sediment fecal and biomass burning biomarkers provide direct evidence for prehistoric human-lit fires in New Zealand

    Deforestation associated with the initial settlement of New Zealand is a dramatic example of how humans can alter landscapes through fire. However, evidence linking early human presence and land-cover change is inferential in most continental sites. We employed a multi-proxy approach to reconstruct anthropogenic land use in New Zealand’s South Island over the last millennium using fecal and plant
    By
    Climate Research and Development Program, Groundwater and Streamflow Information Program, Land Change Science Program, Geosciences and Environmental Change Science Center

    High latitude Southern Hemisphere fire history during the mid-late Holocene (750- 6000 yr BP)

    We determined the specific biomass burning biomarker levoglucosan in an ice core from the TALos Dome Ice CorE drilling project (TALDICE) during the mid- to late Holocene (6000–750 BP). The levoglucosan record is characterized by a long-term increase with higher rates starting at  ∼  4000 BP and peaks between 2500 and 1500 BP. The anomalous increase in levoglucosan centered at  ∼  2000 BP is consis
    By
    Climate Research and Development Program, Groundwater and Streamflow Information Program, Geosciences and Environmental Change Science Center

    A North American Hydroclimate Synthesis (NAHS) of the Common Era

    This study presents a synthesis of century-scale hydroclimate variations in North America for the Common Era (last 2000 years) using new age models of previously published multiple proxy-based paleoclimate data. This North American Hydroclimate Synthesis (NAHS) examines regional hydroclimate patterns and related environmental indicators, including vegetation, lake water elevation, stream flow and
    By
    Water Resources, Climate Research and Development Program, Energy Resources Program, Groundwater and Streamflow Information Program, Mineral Resources Program, National Laboratories Program, Science and Decisions Center, Florence Bascom Geoscience Center, Geology, Minerals, Energy, and Geophysics Science Center, Geosciences and Environmental Change Science Center, St. Petersburg Coastal and Marine Science Center

    Non-USGS Publications**

    Van Marle, M.J.E.; Kloster, Silvia; Magi, B.I.; Marlon, J.R.; Daniau, Anne-Laure; Field, R.D.; Arneth, Almut; Forrest, Matthew; Hantson, Stijn; Kehrwald, N.M.; Knorr, Wolfgang; Lasslop, Gitta; Li, Fang; Mangeon, Stéphane; Yue, Chao; Kaiser, J.W.; and van der Werf, G.R., 2017, Historic global biomass burning emissions for CMIP6 (BB4CMIP) based on merging satellite observations with proxies and fire models (1750-2015): Geoscientific Model Development, v. 10, iss. 9.
    Battistel, D., Argiriadis, E., Kehrwald, N., Spigariol, M., Russell, J.M., Barbante, C., 2017, Fire and human record at Lake Victoria, East Africa during the Early Iron Age: Did humans or climate cause massive ecosystem changes?: The Holocene, DOI: 10.1177/0959683616678466
    Gabrielli, P., Barbante, C., Bertagna, G., Merto, M., Binder, D., Carton, A., Carturan, L., Cazorzi, F., Cozzi, C., Dalla Dontana, G., Davis, M., De Blasi, F., Dinale, R., Draga, G., Dreossi, G., Festi, D., Frezzotti, M., Gabrieli, J., Galos, S.P., Ginot, P., Heidenwolf, P., Jenk, T.M., Kehrwald, N.M., Kenny, D., Magand, O., Mair, V., Mikhalenko, C., Lin, P.N., Oeggl, K., Piffer, G., Rinaldi, M., Schotterer, U., Schwikowski, M., Seppi, R., Spolaor, A., Stenni, B., Tonidandel, D., Uglietti, C., Zagorodnov, V., Zanoner, T., Sennaro, P., 2016, Age of the Mt. Ortles ice cores, the Tyrolean Iceman and glaciation of the highest summit of South Tyrol since the Northern Hemisphere Climatic Optimum: Cryosphere, 10, 6, 2779-2797, DOI:10.5194/tc-10-2779-2016
    Brovkin, V, Brücher, T., Kleinen, T., Zaehle, S., Joos, F., Roth, R., Spahni, R., Schmitt, J., Fischer, H., Leuenberger, M., Stone, E., Ridgewell, A., Chappellaz, J., Kehrwald, N., Barbante, C., Blunier, T., Dahl Jensen, D., 2016, Comparative carbon cycle dynamics of past and present interglacials: Quaternary Science Reviews, 137, 15-32, DOI/10.1016/j.quascirev.2016.01.028
    Zangrando, R., Barbaro, E., Vecchiato, M., Kehrwald, N., Barbante, C., Gambaro, A., 2016, Levoglucosan and phenols in marine, coastal and inland Antarctic aerosols: Science of the Total Environment, 544, 606-616, doi:10.1016/j.scitotenv.2015.11.166
    Zennaro, P., N. Kehrwald, J. Marlon, W. F. Ruddiman, T. Brücher, C. Agostinelli, D. Dahl-Jensen, R. Zangrando, A. Gambaro, and C. Barbante, 2015, Europe on fire three thousand years ago: Arson or climate?: Geophys. Res. Lett., 42, 5023–2033. doi: 10.1002/2015GL064259.
    Schüpbach, S., Kirchgeorg, T., Colombaroli, D., Beffa, G., Radaelli, M., Kehrwald, N., Barbante, C., 2015, Combining charcoal sediment and molecular markers to infer a Holocene fire history in the Maya lowlands of Petén, Guatemala: Quaternary Science Reviews 05/2015; 115. DOI:10.1016/j.quascirev.2015.03.004
    Portenga, E.W., Bierman, P.R., Duncan, C., Corbett, L.B., Kehrwald, N.M., Rood, D.H., 2015, Erosion rates of the Bhutanese Himalaya determined using in situ-produced 10Be: Geomorphology, 233, 122-126 doi:0.1016/j.geomorph.2014.09.027
    Kehrwald, N., Zennaro, P., Schüpbach, S., Kirchgeorg, T., McConnell, J.R., Zangrando, R., Gambaro, A., Barbante, C., 2015, Two thousand years of boreal biomass burning recorded in the NEEM ice cores: PAGES Magazine Vol. 23, 1, 14-15
    Wang, N., Xiaobo, W., Kehrwald, N., Li, Z., Li, Q., Jiang, X., Pu, J., 2015, Fukushima Nuclear Accident Recorded in Tibetan Plateau Snow Pits: PloS ONE, 10 (2) e0116580
    Gabrielli, P, Hardy, D.R., Kehrwald, N., Davis, M., Cozzi, G., Turetta, C., Barbante, C., Thompson, L.G., 2014, Deglaciated areas of Kilimanjaro as a source of volcanic trace elements deposited on the ice cap during the late Holocene: Quaternary Science Reviews, 93, 1-10, DOI:10.1016/j.quascirev.2014.03.007
    Guo, Z., Wang, N., Kehrwald, N.M., Mao, R., Wu, H., Wu, Y., Jiang, X., 2014, Temporal and spatial changes in Western Himalayan firn line altitudes from 1998 to 2009: Global and Planetary Change, 118, 97-105. DOI: 10.1016/j.gloplacha.2014.03.012
    Kirchgeorg, T., Schüpbach, S. Kehrwald, N., McWethy, D., Barbante, C., 2014, Method for determining levoglucosan, mannosan and galactosan in sediment to reconstruct past fire activity: Organic Geochemistry, 71, 1-6, DOI:10.1016/j.orggeochem.2014.02.014
    Zennaro, P., Kehrwald, N., McConnell, J., Schüpbach, S, Masselli, O., Marlon, J., Zangrando, R., Vallelonga, P., Spolaor, A., Varin, C., Borrotti, M., Gambaro, A., Barbante, B., 2014, Fire in ice: two millennia of Northern Hemisphere fire history from the Greenland NEEM ice core: Climate of the Past, 10, 1905–1924, 2014 www.clim-past.net/10/1905/2014/ doi:10.5194/cp-10-1905-2014
    Kehrwald, N., Whitlock, C., Barbante, C., Brovkin, V., Daniau, A-L-. Kaplan, J.O., Marlon, J.R., Power, M.J., Thomicke, K., Van der Werf, G., 2013, Fire Research: Linking Past, Present and Future Data: EOS, Vol. 94, No. 46, 12 November 2013, DOI: 10.1002/2013EO460001
    Barbante, C., Kehrwald, N., Marianelli, P., Vinther, B. M.,Cozzi, G., Hammer, C., Clausen, H., Siggard Andersen, M., 2013, Greenland ice core evidence of the 79 AD Vesuvius eruption: Climate of the Past, 9, 1221–1232, 2013 www.clim-past.net/9/1221/2013/ doi:10.5194/cp-9-1221-2013
    Spolaor, A., Vallelonga, P., Plane, J.M.C, Kehrwald N., Gabrieli J., Varin C., Turetta C., Cozzi G., Boutron C. and Barbante C., 2013, Halogen species record Antarctic sea ice over glacial-interglacial periods: Atmospheric Chemistry and Physics, 13, 6623–6635, 2013 www.atmos-chem-phys.net/13/6623/2013/ doi:10.5194/acp-13-6623-2013
    Spolaor A., Vallelonga P., Gabrieli J., Kehrwald N., Turetta C., Cozzi G., Poto L., Plane J.M.C., Boutron C.F., Barbante C., 2013, Speciation analysis of iodine and bromine at picogram-per-gram levels in polar ice: Analytical and Bioanalytical Chemistry, DOI: 10.1007/s00216-012-5806-0
    Zangrando, R., Barbaro, E., Zennaro, P., Rossi, S., Kehrwald, N.M., Gabrieli, J., Barbante, C., Gambaro, A., 2013, Biomass burning molecular markers in Arctic aerosols: Environmental Science and Technology, 47, 8565−8574, dx.doi.org/10.1021/es400125r
    Kirchgeorg, T., Dreyer, A., Gabrieli, J., Kehrwald, N., Sigl, M., Schwikowski, M., Boutron, C., Gambaro, A., Barbante, C., Ebinghaus, R., 2013, Temporal Variations of Perfluoroalkyl Substances and Polybromintad Diphenyl Ethers in Alpine Snow: Environmental Pollution 178, 367-374.
    Spolaor, A., Vallelonga, P., Cozzi, G., Gabrieli, J., Varin, C., Kehrwald, N., Zennaro, P., Boutron, C., Barbante, C., 2013, Iron speciation influences iron bioavailability over glacial-interglacial cycles: Geophysical Research Letters, 40, 8, 618–1623, DOI: 10.1002/grl.50296
    Poto, L., Gabrieli, J., Crowhurst, S., Appleby, P.G., Ferretti, P., Zaccone, C., Surian, N., Ferretti, P., Cozzi, G., Turetta, C., Kehrwald, N.M., Barbante, C., 2013, The first continuous last Late Glacial - Holocene peat bog record from the Dolomites (NE Italian Alps): Quaternary International, http://dx.doi.org/10.1016/j.quaint.2013.05.001
    Kehrwald, N., P. Zennaro, Barbante, C., 2013, Biomass burning records over the present and past interglacial periods: PAGES News, 21, 1
    Kehrwald, N., Zangrando, R., Gabrielli, P., Barbante, C., Gambaro, A., 2012, Levoglucosan as a specific marker of fire events in Greenland snow: Tellus B, 64, May. 2012. Available at: http://www.tellusb.net/index.php/tellusb/article/view/18196
    Scalabrin, E., Zangrando, R., Barbaro, E., Kehrwald, N, Gabrieli, J., Barbante, C., Gambaro, A., 2012, Amino acids in Arctic aerosols: Atmospheric Chemistry and Physics 12, 10453-10463, doi:10.5194/acp-12-10453-2012
    Gabrielli, P., Barbante, C., Carturan, L., Cozzi, G., Dalla Fontana, G., Dinale, R., Draga, G., Gabrieli, J., Kehrwald, N., Mair, V., Mikhalenko, G., Seppi, R., Spolaor, A., Thompson, L.G., Tonidandel, D., 2012, Discovery of cold ice in a deep drilling site in the Eastern European Alps: Geografia Fisica e Dinamica Quaternaria, 35, 101-105, Doi: 10.4461/GFDQ.2012.35.10
    Gabrieli, J., Carturan, L., Gabrielli, P., Kehrwald, N., Turetta, C., Cozzi, G., Spolaor, A., Dinale, R., Staffler, H., Seppi, R., Dalla Fontana, G., Thompson, L.G., Barbante, C., 2011, Impact of Po Valley emissions on the highest glacier of the Eastern European Alps: Atmospheric Chemistry and Physcis, 11, 15, 80-87-8102, Doi:10.5194/acp-11-8087-2011
    Kehrwald, N., McCoy, W., Thibeault, J., Burns, S., Oches, E., 2010, Paleoclimatic implications of modern and LGM European land-snail shell δ18O: Quaternary Research 74, 1, 167-177.
    Kehrwald, N., Zangrando, R., Gambaro, A., Barbante, C., 2010, Fire and climate: Biomass burning recorded in ice and lake cores: European Physical Journal, 9, 105-114, Doi: 10.1051/epjconf/201009008
    Kehrwald, N., Zangrando, R., Gambaro, A., Cescon, P., Barbante, C., 2010, Specific molecular markers in ice cores provide large-scale patters in biomass burning: PAGES News, 18, 2
    Fortner, S., Fountain, A., Lyons, W., Welch, K., Kehrwald, N., 2009, Trace element and major ion concentrations and dynamics in glacier snow and melt: Eliot Glacier, Oregon Cascades: Hydrological Processes, 23, 2987-2996.
    Kehrwald, N.M., Thompson, L.G., Yao, T., Mosley-Thompson, E., Schotterer, U., Alfimov, V., Beer, J., Eikenberg, J., Davis, M.E., 2008, Mass loss on Himalayan glacier endangers water resources: Geophysical Reserch Letters, 35, L22503, doi:10.1029/2008GL035556
    Gardner, T., Marshall, J., Merritts, D., Bee, B., Burgette, R., Burton, E., Cooke, J.,Kehrwald, N., Protti, M., Fisher, D., Sak, P., 2001, Holocene forearc block rotation in response to seamount subduction, southeastern Peninsula, Costa Rica: Geology, 29, 2, 151-154.

    **Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.

  • Science
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    Coring on the Juneau Icefield

    Fire and vegetation changes recorded in Alaskan ice cores

    The past decade has comprised major fires in central Alaska and Siberia. Fire histories from ice cores in the North Pacific (Denali and the Juneau Icefield) record interactions between changing temperature, precipitation, and biomass burning. We aim to quantify what vegetation burned in the past (hardwoods versus softwoods versus grasses) using ratios of levoglucosan, mannosan and galactosan, and...
    By
    Geosciences and Environmental Change Science Center
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    Fire and vegetation changes recorded in Alaskan ice cores

    The past decade has comprised major fires in central Alaska and Siberia. Fire histories from ice cores in the North Pacific (Denali and the Juneau Icefield) record interactions between changing temperature, precipitation, and biomass burning. We aim to quantify what vegetation burned in the past (hardwoods versus softwoods versus grasses) using ratios of levoglucosan, mannosan and galactosan, and...
    Learn More
    link
    Doing USGS fieldwork at Bear Lake, CO showing location, raft, and personnel

    Fire, human activity, and climate records in southwestern US sediments

    This research aims to determine if climate change or human activity was the primary driver of fire activity in southwestern Colorado.
    By
    Geosciences and Environmental Change Science Center
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    Fire, human activity, and climate records in southwestern US sediments

    This research aims to determine if climate change or human activity was the primary driver of fire activity in southwestern Colorado.
    Learn More
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    Bear Lake, Colorado

    Did we start the fire? Climate, Fire and Humans

    The past decade encompasses some of the most extensive fire activity in recorded history. An area the size of Vermont (~24,000 km2) burned in a single Siberian fire in the summer of 2019 (Kehrwald et al., 2020 and references therein) while Australia, Indonesia and the Amazon have all experienced their most intense fires in recorded history (van Wees et al, 2021 and references therein). As more...
    By
    Climate Research and Development Program, Geosciences and Environmental Change Science Center
    link

    Did we start the fire? Climate, Fire and Humans

    The past decade encompasses some of the most extensive fire activity in recorded history. An area the size of Vermont (~24,000 km2) burned in a single Siberian fire in the summer of 2019 (Kehrwald et al., 2020 and references therein) while Australia, Indonesia and the Amazon have all experienced their most intense fires in recorded history (van Wees et al, 2021 and references therein). As more...
    Learn More
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    Drilling firn cores on the Juneau Icefield, Alaska

    Terrestrial Records of Holocene Climate Change: Fire, climate and humans

    Large wildfires have raged across the western Americas in the past decade including the Las Conchas, New Mexico fire that burned 44,000 acres in a single day in 2011 (Orem and Pelletier, 2015, Geomorphology 232: 224-238, and references therein), the 2016 Fort McMurray, Alberta fire that required evacuating an entire city, and the 2015 Alaskan fire season that burned more than 5 million acres...
    By
    Climate Research and Development Program, Geosciences and Environmental Change Science Center
    link

    Terrestrial Records of Holocene Climate Change: Fire, climate and humans

    Large wildfires have raged across the western Americas in the past decade including the Las Conchas, New Mexico fire that burned 44,000 acres in a single day in 2011 (Orem and Pelletier, 2015, Geomorphology 232: 224-238, and references therein), the 2016 Fort McMurray, Alberta fire that required evacuating an entire city, and the 2015 Alaskan fire season that burned more than 5 million acres...
    Learn More
  • Data

    Investigating fire frequency and vegetative combustion sources using wildland fire tracer molecules archived in the Juneau Icefield of Alaska

    The past decade includes some of the most extensive boreal forest fires in the historical record. Environmental drivers include warming temperatures, changing precipitation patterns, desiccation of thick organic soil layers, and increased ignition frequency from lightning. Wildland fires produce smoke aerosols that can travel thousands of kilometers, before blanketing the surfaces on which they fa
    By
    Water Resources, Climate Research and Development Program, Geosciences and Environmental Change Science Center
  • News
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    Friday's Findings - January 8 2020

    We Did Start the Fire: Humans, Climate and Fire in the Holocene

    Date: January 8, 2021 from 2-2:30 p.m. eastern time

    Speaker: Natalie Kehrwald, Research...

    Read Article
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    Fire Aerosols Affect Southeastern Alaskan Glaciers

    This article is part of the Fall 2020 issue of the Earth Science Matters Newsletter.

    Read Article
  • Multimedia
    Coring on the Juneau Icefield
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    Crevices on glacier, Juneau Icefield
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    Glacier, Juneau Icefield
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