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Outline

Title
Abstract
Introduction
Regional Summary: Idaho, Montana, Wyoming Rockies
Regional Summary: Utah and Colorado
Regional Summary: Arizona and New Mexico
Regional Summary: California
Climate Change Implications for Land Management
Conclusion
References

Climate and Wildfire in Western US Forests

Profile image of Tom SwetnamTom SwetnamProfile image of Leroy WesterlingLeroy Westerling

Abstract

Wildfire in western U.S. federally managed forests has increased substantially in recent decades, with large (>1000 acre) fires in the decade through 2012 over five times as frequent (450 percent increase) and burned area over ten times as great (930 percent increase) as the 1970s and early 1980s. These changes are closely linked to increased temperatures and a greater frequency and intensity of drought. Projected additional future warming implies that wildfire activity may continue to increase in western forests. However, the interaction of changes in climate, fire and other disturbances, vegetation and land management may eventually transform some forest ecosystems and fire regimes, with changes in the spatial extent of forest and fire regime types. In particular, forests characterized by infrequent, high-severity stand replacing fire may be highly sensitive to warming. Increased wildfire combined with warming may transform these ecosystems such that fuel variability, rather th...

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References (108)

  1. Allen, C.D.; Anderson, R.S.; Jass, R.B. [and others]. 2008. Paired charcoal and tree-ring records of high- frequency Holocene fire from two New Mexico bog sites. International Journal of Wildland Fire. 17(1): 115-130.
  2. Allen, C.D.; Breshears, D.D. 1998. Drought-induced shift of a forest-woodland ecotone: Rapid landscape response to climate variation. Proceedings of the National Academy of Sciences USA. 95(25): 14839-14842.
  3. Allen, C.D.; Savage, M.; Falk, D.A. [and others]. 2002. Ecological Restoration of Southwestern Ponderosa Pine Ecosystems: A Broad Perspective. Ecological Applications. 12: 1418-1433.
  4. Anderson, R.S.; Allen, C.D.; Toney, J.L. [and others]. 2008. Holocene vegetation and fire regimes in subalpine and mixed conifer forests, southern Rocky Mountains, USA. International Journal of Wildland Fire. 17(1): 96-114.
  5. Arndt, D.S.; Baringer, M.O.; Johnson, M.R., eds. 2010: State of the Climate in 2009. Bulletin of the American Meteorological Society. 91(7): S1-S224.
  6. Bailey, R.G. 1996. Ecosystem Geography. Springer-Verlag. New York, New York. 216 pp.
  7. Bahre, C.J. 1986. Wildfire in southeastern Arizona between 1859 and 1890. Desert Plants. 7(4): 190-194.
  8. Baker, W.L. 2009. Fire ecology in Rocky Mountain landscapes. Island Press, Washington, D.C. Balling, R.C.; Meyer, G.A.; Wells, S.G. 1992. Relation of Surface Climate and Burned Area in Yellowstone National Park. Agricultural and Forest Meteorology. 60: 285-293.
  9. Bessie, W.C.; Johnson, E.A. 1995. The relative importance of fuels and weather on fire behavior in subalpine forests in the southern Canadian Rockies. Ecology. 26: 747-762.
  10. Bigio, E.; Swetnam, T.W.; Baisan, C.H. 2010. A comparison and integration of tree-ring and alluvial records of fire history at the Missionary Ridge Fire, Durango, Colorado, USA. The Holocene 20(7): 1047-1061.
  11. Blunden, J.; Arndt, D.S., eds. 2013: State of the Climate in 2012. Bulletin of the American Meteorological Society. 94 (8), S1-S238.
  12. Breshears. D.D.; Cobb, N.S.; Rich, P.M. [and others]. 2005. Regional vegetation die-off in response to global-change-type drought. Proceedings of the National Academy of Sciences USA. 102(42): 15144-15148.
  13. Brown, P.M.; Wu, R. 2005. Climate and disturbance forcing of episodic tree recruitment in a southwestern ponderosa pine landscape. Ecology. 86 (11): 3030-3038.
  14. Brown, J.T.; Hall, B.L.; Westerling, A.L. 2004. The impact of twenty-first century climate change on wildland fire danger in the western United States: An application perspective. Climatic Change. 62: 365-388.
  15. Brown, P.M.; Heyderdahl, E.K.; Kitchen, S.G; Weber, M.H. 2008. Climate effects on historical fires (1630-1900) in Utah. International Journal of Wildland Fire. 17: 28-39.
  16. Caulkin, D.E.; Cohen, J. D.; Finney, M.A.; Thompson, M.P. 2014. Can risk management prevent future wildfire disasters in the Wildland Urban Interface? Proceedings of the National Academy of Sciences USA. 111(2): 746-751.
  17. Cayan, D.R.; Das, T.; Pierce, D.W. [and others]. 2010. Future dryness in the southwest US and the hydrology of the early 21st century drought. Proceedings of the National Academy of Sciences USA. 107(3): 21271-21276.
  18. Cleveland, C. 2012. Ecoregions of the United States (Bailey). Retrieved from http://www.eoearth.org/ view/article/152244
  19. Climate Central. 2012. The Age of Western Wildfires. Climate Central: Princeton, NJ. 19 p. http://www. climatecentral.org/news/report-the-age-of-western-wildfires-14873
  20. Collins, B.; Omi, P.; Chapman, P. 2006. Regional relationships between climate and wildfire-burned area in the Interior West, USA. Canadian Journal of Forest Research. 36: 699-709.
  21. Cooper, C.F. 1960. Changes in vegetation, structure, and growth of southwestern pine forests since white settlement. Ecological Monographs. 30(2): 129-164.
  22. Crimmins, M.A. 2006. Synoptic climatology of extreme fire-weather conditions across the southwest United States. International Journal of Climatology. 26(8): 1001-1016.
  23. Crimmins, M.A.; Comrie, A.C. 2004. Interactions between antecedent climate and wildfire variability across southeastern Arizona. International Journal of Wildland Fire. 13(4): 455-466.
  24. Cross, M.S.; Zavaleta, E.S.; Bachelet, D. [and others]. 2012. The adaptation for conservation targets (ACT) framework: a tool for incorporating climate change into natural resource management. Environmental Management. 50: 341-351.
  25. Dai, A. 2011. Drought under global warming: a review. WIREs Climate Change. 2: 45-65.
  26. Dettinger, M.D. 2006. A component-resampling approach for estimating probability distributions from small forecast ensembles. Climatic Change. 76: 149-168.
  27. Dilling, L.; Lemos, M.C. 2011. Creating usable science: opportunities and constraints for climate knowledge use and their implications for science policy. Global Environmental Change. 21(2): 680-689.
  28. Donnegan, J.A.; Veblen, T.T.; Sibold, J.S. 2001. Climatic and human influences on fire history in Pike National Forest, central Colorado. Canadian Journal of Forest Research. 31: 1526-1539.
  29. Falk, D.A.; Heyerdahl, E.K.; Brown, P.M. [and others]. 2011. Multi-scale controls of historical forest- fire regimes: new insights from fire-scar networks. Frontiers in Ecology and the Environment. doi:10.1890/100052.
  30. Frechette, J.D.; Meyer, G.A. 2009. Holocene fire-related alluvial-fan deposition and climate in ponderosa pine and mixed-conifer forests, Sacramento Mountains, New Mexico, USA. The Holocene 19(4): 639-651. doi:10.1177/0959683609104031.
  31. Fulé, P.Z.; Covington, W.W.; Moore, M.M. 1997. Determining Reference Conditions for Ecosystem Management of Southwestern Poderosa Pine Forests. Ecological Applications. 7(3): 895-908.
  32. Gartner, M.H.; Veblen, T.T.; Sherriff, R.L. [and others]. 2012. Proximity to grasslands influences fire frequency and sensitivity to climate variability in ponderosa pine forests of the Colorado Front Range. International Journal of Wildland Fire. 21: 562-571.
  33. Gershunov, A.; Rajagopalan, B.; Overpeck, J. [and others]. 2013: Future Climate: Projected Extremes. In Garfin, G.; Jardine, A.; Merideth, R.; Black, M.; LeRoy, S., eds. Assessment of Climate Change in the Southwest United States: A Report Prepared for the National Climate Assessment, Southwest Climate Alliance report. Washington, D.C.: Island Press. 126-147.
  34. Gillett, N.P.; Weaver, A.J.; Zwiers, F.W.; Fannigan, M.D. 2004. Detecting the effect of climate change on Canadian forest fires. Geophysical Research Letters. 31. L18211. doi:10.1029/2004GL020876.
  35. Gorte, R. 2013. The rising cost of wildfire protection. A report prepared for Headwater Economics. Available at http://headwaterseconomics.org/wphw/wp-content/uploads/fire-costs-background-report. pdf. Grissino-Mayer, H.; Romme, W.; Floyd, M.; Hanna, D. 2004. Long-term climatic and human influences on fire regimes of the San Juan National Forest, Southwestern Colorado, USA. Ecology. 85: 1708-1724.
  36. Grissino-Mayer, H.D.; Swetnam, T.W. 2000. Century-scale climate forcing of fire regimes in the American Southwest. Holocene. 10(2): 213-220.
  37. Gude, P.H.; Rasker, R.; van den Noort, J. 2008. Potential for Future Development on Fire Prone Lands. Journal of Forestry. 106(4): 198-205.
  38. Gutzler, D.S.; Robbins, T.O. 2011. Climate variability and projected change in the western United States: regional downscaling and drought statistics. Climate Dynamics. 37: 835-849.
  39. Higuera, P.E.; Whitlock, C.; Gage, J.A. 2010. Linking tree-ring and sediment-charcoal records to reconstruct fire occurrence and area burned in subalpine forests of Yellowstone National Park, USA. Holocene. 21: 327-341
  40. Holden, Z.A.; Morgan, P.; Crimmins, M.A. [and others]. 2007. Fire season precipitation variability influences fire extent and severity in a large southwestern wilderness area, United States. Geophysical Research Letters. 34 (16). doi:10.1029/2007GL030804.
  41. Iniguez, J.M.; Swetnam, T.W.; Baisan, C.H. 2009. Spatially and temporally variable fire regimes in Rincon Peak Sky Island, Arizona. Fire Ecology. 5(1): 3-21.
  42. Intergovernmental Panel on Climate Change (IPCC). 2007. Climate Change 2007: The Physical Science Basis (IPCC Secretariat, WMO, Geneva).
  43. Keeley, J.E.; Aplte, G.H.; Christensen, N.L. [and others]. 2009. Ecological Foundations for Fire Management in North American Forest and Shrubland Ecosystems. Gen. Tech. Rep. PNW-GTR-779.
  44. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station.
  45. Kitzberger, T.; Brown, P.M.; Hyerdahl, E.K. [and others]. 2007. Contingent Pacific-Atlantic Ocean influence on multicentury wildfire synchrony over western North America. Proceedings of the National Academy of Sciences USA. 104(2): 543-548.
  46. Knapp, P.A. 1995. Intermountain West lightning-caused fires: Climatic predictors of area burned. Journal of Range Management. 48: 85-91.
  47. Krawchuk, M.A.; Moritz, M.A. 2011. Constraints on global fire activity vary across a resource gradient. Ecology. 92: 121-132.
  48. Lemos, M.C.; Morehouse, B.J. 2005. The co-production of science and policy in integrated climate assessments. Global Environmental Change. 15(1): 57-68.
  49. Littell, J.S.; McKenzie, D.; Peterson, D.L.; Westerling, A.L. 2009. Climate and Ecoprovince Fire Area Burned in Western U.S. Ecoprovinces, 1916-2003. Ecological Applications. 19(4): 1003-1021.
  50. Margolis, E.Q.; Balmat, J. 2009. Fire history and fire-climate relationships along a fire regime gradient in the Santa Fe Municipal Watershed, NM, USA. Forest Ecology and Management. 258(11): 2416- 2430.
  51. Margolis, E.Q.; Swetnam, T.W.; Allen, C.D. 2007. A stand-replacing fire history in upper montane forests of the southern Rocky Mountains. Canadian Journal of Forestry. 37(11): 2227-2241.
  52. McKenzie, D.; Gedalof, Z.; Peterson, D.L.; Mote, P. 2004. Climatic change, wildfire, and conservation. Conservation Biology. 18(4): 890-902.
  53. McWethy, D.B.; Gray, S.T.; Higuera, P.E. [and others]. 2010. Climate and terrestrial ecosystem change in the US Rocky Mountains and Upper Columbia Basin. Natural Resource Report NPS/GRYN/ NRR-2010/260. U.S. Department of the Interior, Fort Collins, CO.
  54. Melillo and others 2013: Third National Climate Assessment Draft Report. United States Global Change Research Program. Washington D.C.1193 pp. Jan.11, 2013. hfp://ncadac.globalchange.gov/
  55. Miller, J.D.; Safford, H.D.; Crimmins, M.; Thode, A.E. 2009. Quantitative Evidence for Increasing Forest Fire Severity in the Sierra Nevada and Southern Cascade Mountains, California and Nevada, USA. Ecosystems. 12: 16-32.
  56. Millspaugh S.H.; Whitlock, C.; Bartlein, P.J. 2004. Postglacial fire, vegetation, and climate history of the Yellowstone-Lamar and central plateau provinces, Yellowstone National Park. In Wallace, L.L., ed. After the fires: The ecology of change in Yellowstone National Park. New Haven, CT: Yale University Press: 10-28.
  57. Moritz, M.A.; Parisien, M.-A.; Batllori, E.; [and others]. 2012. Climate change and disruptions to global fire activity. Ecosphere. 3: 49.
  58. Nash, C.H.; Johnson, E.A. 1996. Synoptic climatology of lighting-caused forest fires in subalpine and boreal forests. Canadian Journal of Forest Research. 26(10) 1859-1874.
  59. National Research Council 2011. Climate stabilization targets: Emissions, Concentrations, and Impacts over Decades to Millennia. Washington, D.C.: The National Academies Press: 286 p.
  60. O'Connor, C.D.; Garfin, G.M.; Falk, D.A. [and others]. 2011. Human Pyrogeography: A New Synergy of Fire, Climate and People is Reshaping Ecosystems across the Globe. Geography Compass 5(6): 329-350.
  61. Osmond, C.B.; Pitelka, L.F.; Hidy, G.M., eds. 1990. Plant Biology of the Basin and Range. Ecological Studies. 80. Springer-Verlag.
  62. Peterson, T.C.; Heim Jr., R.R.; Hirsch, R. [and others]. 2013: Monitoring and Understanding Changes in Heat Waves, Cold Waves, Floods, and Droughts in the United States: State of Knowledge. Bulletin of the American Meteorological Society. 94: 821-834.
  63. Pierce, J.L.; Meyer, G.A.; Jull, A.J. 2004. Fire-induced erosion and millennial-scale climate change in northern ponderosa pine forests. Nature. 432(7013): 87-90.
  64. Preisler, H.K.; Westerling, A.L.; Gebert, K.M. [and others]. 2011. Spatially explicit forecasts of large wildland fire probability and suppression costs for California. International Journal of Wildland Fire. 20: 508-517.
  65. Ray, A.J.; Barsugli, J.J.; Wolter, K. [and others]. 2010. Rapid-response climate assessment to support the FWS status review of the American pika. NOAA Earth Systems Research Laboratory, Boulder, Colorado, USA. Available at: http://www.esrl.noaa.gov/psd/news/2010/pdf/pika_report_final.pdf.
  66. Renkin, R.A.; Despain, D.G. Despain. 1992. Fuel moisture, forest type, and lightning-caused fire in Yellowstone National Park. Canadian Journal of Forest Research. 22(1): 37-45.
  67. Rollins, M.G.; Swetnam, T.W.; Morgan, P. 2001. Evaluating a century of fire patterns in two Rocky Mountain wilderness areas using digital fire atlases. Canadian Journal of Forest Research. 31(12): 2107-2123.
  68. Romme, W.H.; Despain, D.G. Despain. 1989. Historical Perspective on the Yellowstone Fires of 1988. BioScience. 39(10): 695-699.
  69. Romme, W.H.; Allen, C.D.; Bailey, J.D. [and others]. 2009. Historical and modern disturbance regimes, stand structures, and landscape dynamics in piñon-juniper vegetation of the western U.S. Rangeland Ecology and Management. 62(3): 203-222.
  70. Roos, C.I.; Swetnam, T.W. 2012. A 1,416-year reconstruction of annual, multi-decadal, and centennial variability in area burned for ponderosa pine forests of the southern Colorado Plateau region, Southwest US. The Holocene. 22: 281-290.
  71. Schoennagel, T.; Sherriff, R.L.; Veblen, T.T. 2011. Fire history and tree recruitment in the upper montane zone of the Colorado Front Range: implications for forest restoration. Ecological Applications. 21: 2210-2222.
  72. Schoennagel, T.; Veblen, T.T.; Romme, W.H. 2004. The interaction of fire, fuels and climate across Rocky Mountain forests. BioScience. 54: 661-676.
  73. Seager, R.; Ting, M.; Held, I. [and others]. 2007. Model projections of an imminent transition to a more arid climate in southwestern North America. Science. 316: 1181-1184.
  74. Sheffield, J.; Goteti, G.; Wen, F.H.; Wood, E.F. 2004. A simulated soil moisture based drought analysis for the United States. Journal of Geophysical Research. 109: Geophys. Res. 109, D24108.
  75. Sherriff, R.S.; Veblen, T.T. 2008. Variability in fire-climate relationships in ponderosa pine forests in the Colorado Front Range. International Journal of Wildland Fire. 17: 50-59.
  76. Sibold, J.S.; Veblen, T.T. 2006. Relationships of subalpine forest fires in the Colorado Front Range to interannual and multi-decadal scale climatic variation Journal of Biogeography. 33: 833-842.
  77. Soja, A.J.; Tchebakova, N.M.; French, N.H.F. [and others]. 2007. Climate-induced boreal forest change: Predictions versus current observations. Global and Planetary Change. 56: 274-296.
  78. Spracklen, D.V.; Mickley, L.J.; Logan, J.A. [and others]. 2009. Impacts of climate change from 2000 to 2050 on wildfire activity and carbonaceous aerosol concentrations in the western United States, Journal of Geophysical Research. 114: D20301.
  79. Stephens, S.L.; Martin, R.E.; Clinton, N.E. 2007. Prehistoric fire area and emissions from California's forests, woodlands, shrublands, and grasslands. Forest Ecology and Management. 251: 205-216.
  80. Stephenson, N.L. 1988. Actual evapotranspiration and deficit: biologically meaningful correlates of vegetation distribution across spatial scales. Journal of Biogeography. 25: 855-870.
  81. Swetnam, T.W.; Baisan, C.H. 1996. Historical fire regime patterns in the Southwestern United States since AD 1700. In Allen, C.D., ed. Fire effects in Southwestern Forests, Proceedings of the Second La Mesa Fire Symposium, Los Alamos, New Mexico, March 29-31, 1994. USDA Forest Service General Technical Report RM-GTR-286: 11-32.
  82. Swetnam, T.W.; Baisan, C.H. 2003. Tree-ring reconstructions of fire and climate history in the Sierra Nevada and Southwestern United States. In Veblen, T.T.; Baker, W.; Montenegro, G.; Swetnam, T.W., eds. Fire and Climatic Change in Temperate Ecosystems of the Western Americas. Ecological Studies Vol. 160. Springer, New York. 158-195 pp.
  83. Swetnam, T.W.; Betancourt, J.L. 1990. Fire-southern oscillation relations in the southwestern United States. Science. 249(4972): 1017-1020.
  84. Swetnam, T.W.; Brown, P.M. 2010. Climatic inferences from dendroecological reconstructions. In Hughes, M.K.; Swetnam, T.W.; Diaz, H.F., eds. Dendroclimatology: Developments in Paleoenvironmental. 11: 263-295.
  85. Swetnam, T.W.; Betancourt. 1998. Mesoscale Disturbance and Ecological Response to Decadal Climatic Variability in the American Southwest. Journal of Climate. 11: 3128-3147.
  86. Swetnam, T.W.; Baisan, C.H.; Morino, K.; Caprio, A.C. 1998. Fire history along elevational transects in the Sierra Nevada, California. Final Report To Sierra Nevada Global Change Research Program United States Geological Survey, Biological Resources Division Sequoia, Kings Canyon, and Yosemite National Parks.
  87. Swetnam, T.W.; Baisan, C.H.; Kaib, J.M. 2001. Forest fire histories in the sky islands of La Frontera. In Webster, G.L.; Bahre, C.J., eds. Changing Plant Life of La Frontera: Observations on Vegetation in the United States/Mexico Borderlands. University of New Mexico Press, Albuquerque. 95-119 pp.
  88. Turner, M.G.; Donato, D.C.; Romme, W.H. 2013. Consequences of spatial heterogeneity for ecosystem services in changing forest landscapes: priorities for future research. Landscape Ecology. 28: 1081- 1097.
  89. Veblen, T.T.; Kitzberger T.; Donnegan, J. 2000. Climatic and human influences on fire regimes in ponderosa pine forests in the Colorado Front Range. Ecological Applications. 10: 1178-1195.
  90. Vose, J.M.; Peterson, D.L.; Patel-Weynand, T., eds. 2012. Effects of climatic variability and change on forest ecosystems: a comprehensive science synthesis for the U.S. forest sector. Gen. Tech. Rep. PNW-GTR-870. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 265 p.
  91. Weaver, H. 1951. Fire as an ecological factor in the Southwestern Ponderosa Pine Forests. Journal of Forestry. 49: 93-98.
  92. Weeks, D.; Malone, P.; Welling, L. 2011. Climate change scenario planning: a tool for managing parks into uncertain futures. Park Science. 28: 26-33.
  93. Weiss, J.L.; Castro, C.L.; Overpeck, J.T. 2009. Distinguishing Pronounced Droughts in the Southwestern United States: Seasonality and Effects of Warmer Temperatures. Journal of Climate. 22: 5918-5932.
  94. Westerling, A.L.; Brown, T.J.; Gershunov, A. [and others]. 2003. Climate and Wildfire in the Western United States. Bulletin of the American Meteorological Society 84(5): 595-604.
  95. Westerling, A.L.; Gershunov, A.; Cayan, D.R.; Barnett, T.P. 2002. Long lead statistical forecasts of area burned in western U.S. wildfires by ecosystem province. International Journal of Wildland Fire. 11(4): 257-266.
  96. Westerling, A.L.; Hidalgo, H.G.; Cayan, D.R.; Swetnam, T.W. 2006. Warming and Earlier Spring Increases Western U.S. Forest Wildfire Activity. Science. 313: 940-943.
  97. Westerling, A.L.; Bryant, B.P. 2008. Climate Change and Wildfire in California. Climatic Change. 87: s231-249.
  98. Westerling, A.L. 2009. Wildfires. In Schneider, S.H.; Rosencranz, A.; Mastrandrea, M.D.; Kuntz- Duriseti, K., eds. Climate Change Science and Policy. Washington, D.C.: Island Press.
  99. Westerling, A.L.; Turner, M.G.; Smithwick, E.H. [and others]. 2011a: Continued warming could transform Greater Yellowstone fire regimes by mid-21st Century Proceedings of the National Academy of Sciences USA. 108(32): 13165-13170.
  100. Westerling, A.L.; Bryant, B.P.; Preisler, H.K. [and others]. 2011b: Climate Change and Growth Scenarios for California Wildfire Climatic Change, 109(s1): 445-463.
  101. Whitlock, C.; Shafer, S.L.; Marlon, J. 2003. The role of climate and vegetation change in shaping past and future fire regimes in the northwestern US and the implications for ecosystem management. Forest and Ecological Management. 178: 5-21.
  102. Whitlock, C.; Marlon, J.; Briles, C. [and others]. 2008. Long-term relations among fire, fuel, and climate in the northwestern US based on lake-sediment studies. International Journal of Wildland Fire. 17: 72-83.
  103. Williams, A.P.; Allen, C.D.; Millar, C.I. [and others]. 2010. Forest responses to increasing aridity and warmth in the southwestern United States. Proceedings of the National Academy of Sciences USA/ 107(50): 21289-21294.
  104. Williams, A.P.; Allen, C.D.; Macalady, A.K. 2013. Temperature as a potent driver of regional forest drought stress and tree mortality. Nature Climate Change. 3: 292-297.
  105. Wuebbles, D.; Meehl, G.; Hayhoe, K. [and others]. 2013. CMIP5 Climate Model Analyses: Climate Extremes in the United States Bulletin of the American Meteorological. Early e-view: doi:10.1175/ BAMS-D-12-00172.1
  106. Yue, X.; Mickley, L.J.: Logan, J.A.; Kaplan, J.O. 2013. Ensemble projections of wildfire activity and carbonaceous aerosol concentrations over the western United States in the mid-21st century. Atmospheric Environment. 77: 767-780.
  107. Yue, X.; Mickley, L.J.: Logan. 2013. Projection of wildfire activity in southern California in the mid- 21st century, submitted to Climate Dynamics. doi: 10.1007/s00382-013-2022-3.
  108. This paper received peer technical review. The content of the paper reflects the views of the authors, who are responsible for the facts and accuracy of the information herein.

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