| Drought in the Western Great Plains, 1845-56: Impacts and Implications | |
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Drought in the Western Great Plains, 1845-56: Impacts and Implications
Bulletin of the American Meteorological Society, 83, 1485-1493, October 2002. Connie A. Woodhouse 1, 2, Jeffrey J. Lukas2, and Peter M. Brown3.
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NOAA Paleoclimatology Program
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| A sustained mid-19th century drought in the western Great Plains has been indicated by a tree-ring analysis of trees flanking the western Great Plains, and in tree-ring reconstructions of drought and streamflow for eastern Colorado and the Colorado Front Range. The development of new tree-ring chronologies for the western Great Plains, in combination with existing chronologies, now enables a more detailed assessment of the spatial and temporal characteristics of this drought. The analysis of a set of drought-sensitive tree-ring chronologies ranging from the northwestern Great Plains to central New Mexico indicates a core area of drought from south-central Wyoming to northeastern New Mexico for the years 1845-56. Drought was particularly severe in the years 1845-48, 1851, and 1854-56, contracting and affecting smaller regions in intervening years. The impact of this drought on natural ecosystems and human activities is difficult to gauge because of the paucity of historical documents and the confounding effects of land use changes occurring over the same period. However, it is probable that this drought played a role in the decimation of bison herds in the second half of the 19th century. Were it to occur today, this relatively small but persistent drought would have significant impacts on the Colorado Front Range metropolitan area and the agricultural regions of eastern Colorado. | |
| DATA: Download the eastern Colorado PDSI reconstruction data from the WDC Paleo Archive.
Many of the tree ring chronologies utilized in this study are available from the
International Tree Ring Data Bank. |
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Figure 2. Locations of tree-ring chronologies. Outline indicates core drought region for 1845-1856. Chronology sites are numbered and correspond to those listed in Fig. 3. Chronologies selected were from species known to be sensitive to drought (ponderosa pine, Pinus ponderosa; Douglas-fir, Pseudotsuga menziesii; pinyon pine, Pinus edulis; and post oak, Quercus stellata), and were taken to be proxies of drought (generally winter/spring in the south grading to spring/early summer in the north). All but the three Montana chronologies (courtesy of David Meko) were obtained or are now available from the World Data Center for Paleoclimatology’s International Tree-Ring Data Bank (ITRDB). In all but three cases (the Montana sites, where raw data were not available), raw ring width measurements were used to generate tree-ring chronologies (ARSTAN; Cook 1985) to insure that the same standardization process and conservative detrending methods were used for all chronologies. Also included were 11 newly generated chronologies from isolated ponderosa pine, Douglas-fir, and pinyon pine woodlands growing in the Great Plains in Nebraska, eastern and central Colorado, and northeastern New Mexico (Woodhouse and Brown 2001). Except for the three Montana chronologies, residual chronologies, from which low-order autocorrelation presumed to be biological in origin has been removed (Fritts 1976), were used for this study. |
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To read or view the full study, please visit the
Allen Press website. It was published in Bulletin of the American Meteorological Society, 83, 1485-1493, October 2002. | |
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This project was funded by grant ATM-9729751 from the U.S. National Science Foundation. |
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Contact Us National Oceanic and Atmospheric Administration 6 December 2002
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