• Abatzoglou, J. T., 2013: Development of gridded surface meteorological data for ecological applications and modelling. Int. J. Climatol., 33, 121131, https://doi.org/10.1002/joc.3413.

    • Search Google Scholar
    • Export Citation
  • Abatzoglou, J. T., and C. A. Kolden, 2013: Relationships between climate and macroscale area burned in the western United States. Int. J. Wildland Fire, 22, 10031020, https://doi.org/10.1071/WF13019.

    • Search Google Scholar
    • Export Citation
  • Abatzoglou, J. T., and A. P. Williams, 2016: Impact of anthropogenic climate change on wildfire across western US forests. Proc. Natl. Acad. Sci. USA, 113, 11 77011 775, https://doi.org/10.1073/pnas.1607171113.

    • Search Google Scholar
    • Export Citation
  • Abatzoglou, J. T., A. P. Williams, and R. Barbero, 2019: Global emergence of anthropogenic climate change in fire weather indices. Geophys. Res. Lett., 46, 326336, https://doi.org/10.1029/2018GL080959.

    • Search Google Scholar
    • Export Citation
  • Anderson, M., 2006: The use of fire by Native Americans in California. Fire in California’s Ecosystems, University of California Press, 417430.

    • Search Google Scholar
    • Export Citation
  • Baek, S. H., J. E. Smerdon, B. I. Cook, and A. P. Williams, 2021: U.S. Pacific coastal droughts are predominantly driven by internal atmospheric variability. J. Climate, 34, 19471962, https://doi.org/10.1175/JCLI-D-20-0365.1.

    • Search Google Scholar
    • Export Citation
  • Balch, J. K., J. T. Abatzoglou, M. B. Joseph, M. J. Koontz, A. L. Mahood, J. McGlinchy, M. E. Cattau, and A. P. Williams, 2022: Warming weakens the night-time barrier to global fire. Nature, 602, 442448, https://doi.org/10.1038/s41586-021-04325-1.

    • Search Google Scholar
    • Export Citation
  • CALFIRE, 2021: CALFIRE. State of California, accessed 10 August 2021, http://www.fire.ca.gov/.

  • Chiodi, A. M., B. E. Potter, and N. K. Larkin, 2021: Multi-decadal change in western US nighttime vapor pressure deficit. Geophys. Res. Lett., 48, e2021GL092830, https://doi.org/10.1029/2021GL092830.

    • Search Google Scholar
    • Export Citation
  • Cohen, J. D., and J. E. Deeming, 1985: The National Fire-Danger Rating System: Basic equations. USDA Forest Service Pacific Southwest Forest and Range Experiment Station General Tech. Rep. PSW-GTR-82, 16 pp., https://www.fs.fed.us/psw/publications/documents/psw_gtr082/psw_gtr082.pdf.

  • Crimmins, M. A., and A. C. Comrie, 2004: Interactions between antecedent climate and wildfire variability across south-eastern Arizona. Int. J. Wildland Fire, 13, 455466, https://doi.org/10.1071/WF03064.

    • Search Google Scholar
    • Export Citation
  • Finco, M., B. Quayle, Y. Zhang, J. Lecker, K. A. Megown, and C. K. Brewer, 2012: Monitoring Trends and Burn Severity (MTBS): Monitoring wildfire activity for the past quarter century using Landsat data. Moving from Status to Trends: Forest Inventory and Analysis Symp. 2012, Baltimore, MD, USDA, 222228, https://www.nrs.fs.fed.us/pubs/gtr/gtr-nrs-p-105papers/35finco-p-105.pdf.

  • Fosberg, M. A., 1978: Weather in wildland fire management: The fire weather index. Conf. on Sierra Nevada Meteorology, South Lake Tahoe, CA, Amer. Meteor. Soc., 14.

    • Search Google Scholar
    • Export Citation
  • Goss, M., D. L. Swain, J. T. Abatzoglou, A. Sarhadi, C. A. Kolden, A. P. Williams, and N. S. Diffenbaugh, 2020: Climate change is increasing the likelihood of extreme autumn wildfire conditions across California. Environ. Res. Lett., 15, 094016, https://doi.org/10.1088/1748-9326/ab83a7.

    • Search Google Scholar
    • Export Citation
  • Herring, S. C., N. Christidis, A. Hoell, M. P. Hoerling, and P. A. Stott, 2020: Explaining extreme events of 2018 from a climate perspective. Bull. Amer. Meteor. Soc., 101 (1), S1S140, https://doi.org/10.1175/BAMS-ExplainingExtremeEvents2018.1.

    • Search Google Scholar
    • Export Citation
  • Hersbach, H., and Coauthors, 2020: The ERA5 global reanalysis. Quart. J. Roy. Meteor. Soc., 146, 19992049, https://doi.org/10.1002/qj.3803.

    • Search Google Scholar
    • Export Citation
  • Higuera, P. E., and J. T. Abatzoglou, 2021: Record-setting climate enabled the extraordinary 2020 fire season in the western United States. Global Change Biol., 27, 12, https://doi.org/10.1111/gcb.15388.

    • Search Google Scholar
    • Export Citation
  • Holden, Z. A., and Coauthors, 2018: Decreasing fire season precipitation increased recent western US forest wildfire activity. Proc. Natl. Acad. Sci. USA, 115, E8349E8357, https://doi.org/10.1073/pnas.1802316115.

    • Search Google Scholar
    • Export Citation
  • Homer, C. H., J. A. Fry, and C. A. Barnes, 2012: The National Land Cover Database. U.S. Geological Survey Fact Sheet 2012-3020, 4 pp., https://pubs.usgs.gov/fs/2012/3020/fs2012-3020.pdf.

  • Juang, C. S., A. P. Williams, J. T. Abatzoglou, J. K. Balch, M. D. Hurteau, and M. A. Moritz, 2022: Rapid growth of large forest fires drives the exponential response of annual forest-fire area to aridity in the western United States. Geophys. Res. Lett., 49, e2021GL097131, https://doi.org/10.1029/2021GL097131.

    • Search Google Scholar
    • Export Citation
  • Keeley, J. E., and C. Fotheringham, 2001: Historic fire regime in Southern California shrublands. Conserv. Biol., 15, 15361548, https://doi.org/10.1046/j.1523-1739.2001.00097.x.

    • Search Google Scholar
    • Export Citation
  • Kirchmeier-Young, M., N. Gillett, F. Zwiers, A. Cannon, and F. Anslow, 2019: Attribution of the influence of human-induced climate change on an extreme fire season. Earth’s Future, 7, 210, https://doi.org/10.1029/2018EF001050.

    • Search Google Scholar
    • Export Citation
  • Kumar, A., and M. P. Hoerling, 1998: Annual cycle of Pacific–North American seasonal predictability associated with different phases of ENSO. J. Climate, 11, 32953308, https://doi.org/10.1175/1520-0442(1998)011<3295:ACOPNA>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Marlon, J. R., and Coauthors, 2012: Long-term perspective on wildfires in the western USA. Proc. Natl. Acad. Sci. USA, 109, E535E543, https://doi.org/10.1073/pnas.1112839109.

    • Search Google Scholar
    • Export Citation
  • Mitchell, K. E., and Coauthors, 2004: The multi-institution North American Land Data Assimilation System (NLDAS): Utilizing multiple GCIP products and partners in a continental distributed hydrological modeling system. J. Geophys. Res., 109, D07S90, https://doi.org/10.1029/2003JD003823.

    • Search Google Scholar
    • Export Citation
  • Phuleria, H. C., P. M. Fine, Y. Zhu, and C. Sioutas, 2005: Air quality impacts of the October 2003 Southern California wildfires. J. Geophys. Res., 110, D07S20, https://doi.org/10.1029/2004JD004626.

    • Search Google Scholar
    • Export Citation
  • Romps, D. M., J. T. Seeley, D. Vollaro, and J. Molinari, 2014: Projected increase in lightning strikes in the United States due to global warming. Science, 346, 851854, https://doi.org/10.1126/science.1259100.

    • Search Google Scholar
    • Export Citation
  • Scott, A. C., and I. J. Glasspool, 2006: The diversification of Paleozoic fire systems and fluctuations in atmospheric oxygen concentration. Proc. Natl. Acad. Sci. USA, 103, 10 86110 865, https://doi.org/10.1073/pnas.0604090103.

    • Search Google Scholar
    • Export Citation
  • Seager, R., L. Goddard, J. Nakamura, N. Henderson, and D. E. Lee, 2014: Dynamical causes of the 2010/11 Texas–northern Mexico drought. J. Hydrometeor., 15, 3968, https://doi.org/10.1175/JHM-D-13-024.1.

    • Search Google Scholar
    • Export Citation
  • Seager, R., M. Hoerling, S. Schubert, H. Wang, B. Lyon, A. Kumar, J. Nakamura, and N. Henderson, 2015a: Causes of the 2011–14 California drought. J. Climate, 28, 69977024, https://doi.org/10.1175/JCLI-D-14-00860.1.

    • Search Google Scholar
    • Export Citation
  • Seager, R., A. Hooks, A. P. Williams, B. Cook, J. Nakamura, and N. Henderson, 2015b: Climatology, variability, and trends in the U.S. vapor pressure deficit, an important fire-related meteorological quantity. J. Appl. Meteor. Climatol., 54, 11211141, https://doi.org/10.1175/JAMC-D-14-0321.1.

    • Search Google Scholar
    • Export Citation
  • Seneviratne, S. I., T. Corti, E. L. Davin, M. Hirschi, E. B. Jaeger, I. Lehner, B. Orlowsky, and A. J. Teuling, 2010: Investigating soil moisture–climate interactions in a changing climate: A review. Earth-Sci. Rev., 99, 125161, https://doi.org/10.1016/j.earscirev.2010.02.004.

    • Search Google Scholar
    • Export Citation
  • Shi, H., and Coauthors, 2019: Modeling study of the air quality impact of record-breaking Southern California wildfires in December 2017. J. Geophys. Res. Atmos., 124, 65546570, https://doi.org/10.1029/2019JD030472.

    • Search Google Scholar
    • Export Citation
  • Short, K. C., 2017: Spatial wildfire occurrence data for the United States, 1992–2015 [FPA_FOD_20170508]. 4th ed. Forest Service Research Data Archive, accessed 11 February 2022, https://doi.org/10.2737/RDS-2013-0009.4.

    • Search Google Scholar
    • Export Citation
  • van Wagtendonk, J. W., 2007: The history and evolution of wildland fire use. Fire Ecol., 3, 317, https://doi.org/10.4996/fireecology.0302003.

    • Search Google Scholar
    • Export Citation
  • Webster, P. J., 1982: Seasonality in the local and remote atmospheric response to sea surface temperature anomalies. J. Atmos. Sci., 39, 4152, https://doi.org/10.1175/1520-0469(1982)039<0041:SITLAR>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Wegesser, T. C., K. E. Pinkerton, and J. A. Last, 2009: California wildfires of 2008: Coarse and fine particulate matter toxicity. Environ. Health Perspect., 117, 893897, https://doi.org/10.1289/ehp.0800166.

    • Search Google Scholar
    • Export Citation
  • Westerling, A. L., 2016: Increasing western US forest wildfire activity: Sensitivity to changes in the timing of spring. Philos. Trans. Roy. Soc., B371, 20150178, https://doi.org/10.1098/rstb.2015.0178.

    • Search Google Scholar
    • Export Citation
  • Westerling, A. L., 2018: Wildfire simulations for California’s Fourth Climate Change Assessment: Projecting changes in extreme wildfire events with a warming climate. California Energy Commission Sacramento Rep., 57 pp., https://www.energy.ca.gov/sites/default/files/2019-11/Projections_CCCA4-CEC-2018-014_ADA.pdf.

  • Westerling, A. L., A. Gershunov, T. J. Brown, D. R. Cayan, and M. D. Dettinger, 2003: Climate and wildfire in the western United States. Bull. Amer. Meteor. Soc., 84, 595604, https://doi.org/10.1175/BAMS-84-5-595.

    • Search Google Scholar
    • Export Citation
  • Westerling, A. L., H. G. Hidalgo, D. R. Cayan, and T. W. Swetnam, 2006: Warming and earlier spring increase western US forest wildfire activity. Science, 313, 940943, https://doi.org/10.1126/science.1128834.

    • Search Google Scholar
    • Export Citation
  • Williams, A. P., and Coauthors, 2014: Causes and implications of extreme atmospheric moisture demand during the record-breaking 2011 wildfire season in the southwestern United States. J. Appl. Meteor. Climatol., 53, 26712684, https://doi.org/10.1175/JAMC-D-14-0053.1.

    • Search Google Scholar
    • Export Citation
  • Williams, A. P., and Coauthors, 2015: Correlations between components of the water balance and burned area reveal new insights for predicting forest fire area in the southwest United States. Int. J. Wildland Fire, 24, 1426, https://doi.org/10.1071/WF14023.

    • Search Google Scholar
    • Export Citation
  • Williams, A. P., J. T. Abatzoglou, A. Gershunov, J. Guzman-Morales, D. A. Bishop, J. K. Balch, and D. P. Lettenmaier, 2019: Observed impacts of anthropogenic climate change on wildfire in California. Earth’s Future, 7, 892910, https://doi.org/10.1029/2019EF001210.

    • Search Google Scholar
    • Export Citation
  • Williams, A., K. Anchukaitis, C. Woodhouse, D. Meko, B. Cook, K. Bolles, and E. Cook, 2021: Tree rings and observations suggest no stable cycles in Sierra Nevada cool-season precipitation. Water Resour. Res., 57, e2020WR028599, https://doi.org/10.1029/2020WR028599.

    • Search Google Scholar
    • Export Citation
All Time Past Year Past 30 Days
Abstract Views 366 363 120
Full Text Views 143 140 29
PDF Downloads 133 131 31

Climate Dynamics Preceding Summer Forest Fires in California and the Extreme Case of 2018

View More View Less
  • 1 aLamont-Doherty Earth Observatory, Palisades, New York
  • | 2 bDepartment of Earth and Environmental Sciences, Columbia University, New York, New York
  • | 3 cDepartment of Geography, University of California, Los Angeles, Los Angeles, California
Restricted access

Abstract

Recent record-breaking wildfire seasons in California prompt an investigation into the climate patterns that typically precede anomalous summer burned forest area. Using burned-area data from the U.S. Forest Service’s Monitoring Trends in Burn Severity (MTBS) product and climate data from the fifth major global reanalysis produced by the European Centre for Medium-Range Weather Forecasts (ERA5) over 1984–2018, relationships between the interannual variability of antecedent climate anomalies and July California burned area are spatially and temporally characterized. Lag correlations show that antecedent high vapor pressure deficit (VPD), high temperatures, frequent extreme high temperature days, low precipitation, high subsidence, high geopotential height, low soil moisture, and low snowpack and snowmelt anomalies all correlate significantly with July California burned area as far back as the January before the fire season. Seasonal regression maps indicate that a global midlatitude atmospheric wave train in late winter is associated with anomalous July California burned area. July 2018, a year with especially high burned area, was to some extent consistent with the general patterns revealed by the regressions: low winter precipitation and high spring VPD preceded the extreme burned area. However, geopotential height anomaly patterns were distinct from those in the regressions. Extreme July heat likely contributed to the extent of the fires ignited that month, even though extreme July temperatures do not historically significantly correlate with July burned area. While the 2018 antecedent climate conditions were typical of a high-burned-area year, they were not extreme, demonstrating the likely limits of statistical prediction of extreme fire seasons and the need for individual case studies of extreme years.

Significance Statement

The purpose of this study is to identify the local and global climate patterns in the preceding seasons that influence how the burned summer forest area in California varies year-to-year. We find that a dry atmosphere, high temperatures, dry soils, less snowpack, low precipitation, subsiding air, and high pressure centered west of California all correlate significantly with large summer burned area as far back as the preceding January. These climate anomalies occur as part of a hemispheric scale pattern with weak connections to the tropical Pacific Ocean. We also describe the climate anomalies preceding the extreme and record-breaking burned-area year of 2018, and how these compared with the more general patterns found. These results give important insight into how well and how early it might be possible to predict the severity of an upcoming summer wildfire season in California.

© 2022 American Meteorological Society. For information regarding reuse of this content and general copyright information, consult the AMS Copyright Policy (www.ametsoc.org/PUBSReuseLicenses).

Corresponding author: Tess W. P. Jacobson, tessj@ldeo.columbia.edu

Abstract

Recent record-breaking wildfire seasons in California prompt an investigation into the climate patterns that typically precede anomalous summer burned forest area. Using burned-area data from the U.S. Forest Service’s Monitoring Trends in Burn Severity (MTBS) product and climate data from the fifth major global reanalysis produced by the European Centre for Medium-Range Weather Forecasts (ERA5) over 1984–2018, relationships between the interannual variability of antecedent climate anomalies and July California burned area are spatially and temporally characterized. Lag correlations show that antecedent high vapor pressure deficit (VPD), high temperatures, frequent extreme high temperature days, low precipitation, high subsidence, high geopotential height, low soil moisture, and low snowpack and snowmelt anomalies all correlate significantly with July California burned area as far back as the January before the fire season. Seasonal regression maps indicate that a global midlatitude atmospheric wave train in late winter is associated with anomalous July California burned area. July 2018, a year with especially high burned area, was to some extent consistent with the general patterns revealed by the regressions: low winter precipitation and high spring VPD preceded the extreme burned area. However, geopotential height anomaly patterns were distinct from those in the regressions. Extreme July heat likely contributed to the extent of the fires ignited that month, even though extreme July temperatures do not historically significantly correlate with July burned area. While the 2018 antecedent climate conditions were typical of a high-burned-area year, they were not extreme, demonstrating the likely limits of statistical prediction of extreme fire seasons and the need for individual case studies of extreme years.

Significance Statement

The purpose of this study is to identify the local and global climate patterns in the preceding seasons that influence how the burned summer forest area in California varies year-to-year. We find that a dry atmosphere, high temperatures, dry soils, less snowpack, low precipitation, subsiding air, and high pressure centered west of California all correlate significantly with large summer burned area as far back as the preceding January. These climate anomalies occur as part of a hemispheric scale pattern with weak connections to the tropical Pacific Ocean. We also describe the climate anomalies preceding the extreme and record-breaking burned-area year of 2018, and how these compared with the more general patterns found. These results give important insight into how well and how early it might be possible to predict the severity of an upcoming summer wildfire season in California.

© 2022 American Meteorological Society. For information regarding reuse of this content and general copyright information, consult the AMS Copyright Policy (www.ametsoc.org/PUBSReuseLicenses).

Corresponding author: Tess W. P. Jacobson, tessj@ldeo.columbia.edu
Save