NINETEENTH CENTURY HISTORICAL CLIMATIC DATA IN MOUNTAINOUS REGIONS OF
THE WESTERN UNITED STATES
MOCK, CARY J. (1); MICHAEL HARTMAN (2); CONNIE WOODHOUSE (2); GREGORY J.
CARBONE (1); MICHAEL D. ANDERSON (1); DOUGLAS O. MAYES (1); AND LAURA STROUP
(1)
(1) Department of Geography, University of South Carolina, Columbia, SC 29208, (2)
Paleoclimatology Branch, NOAA National Climatic Data Center, 325 Broadway E/CC23, Boulder,
CO 80305
Historical climatic reconstructions provide a perspective of climatic variability ranging from daily to decadal timescales well before the temporal coverage of the twentieth century (modern) instrumental records. Such reconstructions provide important information on climatic variability and ecological disturbance in mountainous regions related to drought, floods, snowstorms, freezing events, and windstorms. Much unexploited historical climatic data from the mid nineteenth century exists in western North America in the forms of written annals, diaries, newspapers, and early instrumental records. We describe the different types of nineteenth century historical climatic data that are available for the western mountain regions, currently being listed in a Historical Climate Catalogue. We describe several examples of reconstructions, focusing on locations in the Rocky Mountains and the Pacific mountain ranges. The northern
Utah reconstruction, in particular, is the most comprehensive daily reconstruction conducted to date, and it extends back to the early 1850s. Its daily data were carefully assessed concerning quality and homogeneity. Nineteenth century summer temperatures were about 1.5 degrees C lower than those in the twentieth century, corresponding with the latter timeframe of the Little Ice
Age. Highly anomalous wetness is also evident in the northern Utah record during the late 1860s and early 1870s, which exceeds the magnitude of wetness evident in the early 1980s. We also discuss the potential for applying these climate reconstructions to assess historical impacts on society.