• Tree-Ring Bulletin, Volume 43 (1983)

      Unknown author (Tree-Ring Society, 1983)
    • Curves and Align: Some New Computerized Methods for the Analysis of Tree-Ring Data

      Kickert, Ronald N.; Herren-Gemmill, Barbara; Arkley, Rodney; Thomson, Robert E.; Statewide Air Pollution Research Center, University of California, Riverside, California; Institute of Ecology, University of California, Davis, California; Department of Soils and Plant Nutrition, University of California, Berkeley, California; Computer Center, University of California, Berkeley, California (Tree-Ring Society, 1983)
    • Computer-Assisted Quality Control in Tree-Ring Dating and Measurement

      Holmes, Richard L.; Laboratory of Tree-Ring Research, University of Arizona, Tucson (Tree-Ring Society, 1983)
    • Analysis of Tree Rings and Fire Scars to Establish Fire History

      McBride, Joe R.; Department of Forestry and Resource Management, University of California, Berkeley; Department of Landscape Architecture, University of California, Berkeley (Tree-Ring Society, 1983)
      Traditional counting of tree rings between fire scars to establish a fire history is examined for a better understanding of factors influencing fire scar formation and wound healing. The problem of dating fires which burn prior to or after the period of cambial activity is emphasized. A methodology for fire history studies based on fire scar and tree-ring analysis developed by Arno and Sneck (1977) is reviewed and elaborated upon. The importance of crossdating, height of sample cross sections, and problems associated with the extrapolation of data are discussed. Ongoing research involving the examination of the mineral concentration of tree rings and the presence of traumatic resin canals as markers of past fires is reviewed.
    • Modern New Zealand Tree-Ring Chronologies II. Nothofagus meziesii

      Norton, D. A.; Department of Botany, University of Canterbury, Christchurch, New Zealand (Tree-Ring Society, 1983)
      Five modern Nothofagus menziesii tree-ring chronologies, developed from sites near the alpine timberline, South Island, New Zealand, are presented. The properties of the chronologies are described; as a group they have high mean sensitivity values (mean of 0.31), moderate autocorrelation values (mean of 0.42) and moderate common variance values (mean of 31 %). One site, lying some 200 km distant from the others, is the least similar of the five chronologies. It is concluded that both the long length of N. menziesii chronologies and the proximity of trees to the alpine timberline present considerable potential for reconstructing palaeotemperatures.
    • Testing the Significance of Summary Response Functions

      Gray, B. M.; Pilcher, J. R.; Climatic Research Unit, University of East Anglia, Norwich, U. K.; Palaeoecology Centre, The Queen's University of Belfast, Northern Ireland (Tree-Ring Society, 1983)
      A simple method of testing the statistical significance of the summary response function derived by Pilcher and Gray is given and applied to European oak data.
    • Filtering the Effects of Competition from Ring-Width Series

      Blasing, T. J.; Duvick, D. N.; Cook, E. R.; Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee; Lamont-Doherty Geological Observatory, Palisades, New York (Tree-Ring Society, 1983)
      Spline functions were examined and compared with conventional polynomials for use in filtering nonclimatic variance from tree-ring width series. Both types of curve were fitted to ring-width series exhibiting particularly marked effects of competition and release from competition with neighboring trees during the last 100 years. Available climatic data from that interval were used to statistically evaluate the capabilities of each type of function for removing nonclimatic effects and preserving the climatic signal. The results suggest that both types of function can be used successfully for those purposes, though in the presence of extremely rapid changes in growth rate due to a sudden release from competition it may be necessary to divide the ring-width series into two segments and fit a separate curve to each segment. Tightly-fit polynomials seem to be about as effective as splines, but are less desirable from a computational point of view as, for example, when the magnitude of the (negative) exponents of the coefficients exceeds computer capacity. Further, a spline function can be prescribed from its frequency-response characteristics, so it is possible to specify in advance the extent to which it will filter out any potential climatic cycles.
    • Modern New Zealand Tree-Ring Chronologies I. Nothofagus solandri

      Norton, D. A.; Department of Botany, University of Canterbury, Christchurch, New Zealand (Tree-Ring Society, 1983)
      Sixteen modern Nothofagus solandri tree-ring chronologies, developed from sites near the alpine timberline, South Island, New Zealand are presented. The statistical properties of the chronologies are similar, having high mean sensitivity values (mean of 0.34), moderate autocorrelation values (mean of 0.50), and high common variance values (mean of 42 %). However, the chronologies are mainly less than 300 years in length. Examination of interchronology variation suggests that the similarity between two chronologies decreases with increasing distance. It is concluded that these chronologies offer considerable potential for reconstructing palaeoclimates, especially palaeotemperature.