Fire and alluvial chronology in Yellowstone National Park: climatic and intrinsic controls on Holocene geomorphic processes

Fifty ¹⁴ C ages on fire-related events cluster within the intervals of 3300-2900, 2600-2400, 2200-1800, and 1400-800 yr BP and suggest earlier episodes of large fires and fan aggradation around 7500, 5500, and 4600-4000 yr BP. A major pulse of fire-related debris-flow activity between 950 and 800 yr BP coincided with the height of the widely recognized Medieval Warm Period (ca. AD 1050-1200). Instrumental climate records over the last ~100 yr in Yellowstone imply that the intensity and interannual variability of summer precipitation are greater during warmer periods, enhancing the potential for severe short-term drought, major forest fires, and storm-generated fan deposition. -from Authors