• A 1,373 Year Reconstruction of Annual Precipitation for the Southern Rio Grande Basin

      Grissino-Mayer, Henri D.; Baisan, Christopher H.; Swetnam, Thomas W.; Dept. of Physics, Astronomy & Geosciences, Valdosta State University; Laboratory of Tree-Ring Research, University of Arizona; Laboratory of Tree-Ring Research, University of Arizona (Laboratory of Tree-Ring Research, University of Arizona (Tucson, AZ), 1977-11-10)
    • Analysis and Evaluation of the Sources of Variation in Tree-Rings from Mesa Verde National Park (Progress Report)

      Fritts, Harold C.; Smith, David G.; Laboratory of Tree-Ring Research, University of Arizona; Laboratory of Tree-Ring Research, University of Arizona (Laboratory of Tree-Ring Research, University of Arizona (Tucson, AZ), 1962-08-30)
      The study of tree-ring series, called dendrochronology, was originally conceived by A. E. Douglass as a tool for studying sun-spot cycles. He developed a system of cross- dating which provided for the accurate age determination of rings and this made possible the precise dating of archaeological sites. More recently Edmund Schulman used the width measurements of dated tree-rings as estimates of past climatic and stream -flow patterns.Such applications appeared to have greater precision when the tree -ring samples came from so called "sensitive sites" (i.e., drained ridges or slopes). The present study is the first of a series designed to further assess the effect of site and to provide an estimate of the relative magnitude of each of the sources of variation. The study is supported by the National Geographic Society, Wetherill Mesa Project at Mesa Verde National Park.
    • An Approach to Dendroclimatology: Screening by Means of Multiple Regression Techniques

      Fritts, Harold C.; Laboratory of Tree-Ring Research, University of Arizona (Laboratory of Tree-Ring Research, University of Arizona (Tucson, AZ), 1961-02)
    • Circum-Antarctic Paleoclimate from Tree-Ring Analysis: Final Technical Report

      LaMarche, Valmore C., Jr.; Laboratory of Tree-Ring Research, University of Arizona (Laboratory of Tree-Ring Research, University of Arizona (Tucson, AZ), 1978-01-16)
    • Climatic Regimes of the Pacific Sector and Adjacent Continents Since 1600: A Synoptic Description and Comparison of Independent Climate Proxy Records

      Fritts, Harold C.; Laboratory of Tree-Ring Research, University of Arizona (Laboratory of Tree-Ring Research, University of Arizona (Tucson, AZ), 1987-06)
    • Climatic Variations for North America and the North Pacific Since A.D. 1500 as Identified by Well-Dated Tree Rings, and Applied Research Reconstructing Past Climate of the Northern Hemisphere by Use of Tree Rings (Progress Reports)

      Fritts, Harold C.; Ares, M. C.; Blasing, T. J.; Carter, J. R.; Conkey, L. E.; DeWitt, E.; Lofgren, G. R.; Robinson, W. J.; Sherwood, J. A.; Stevens, D. W.; et al. (Laboratory of Tree-Ring Research, University of Arizona (Tucson, AZ), 1977)
    • Comments on TRL 63-48

      Ferguson, C. W.; Laboratory of Tree-Ring Research, University of Arizona (Laboratory of Tree-Ring Research, University of Arizona (Tucson, AZ), 1974-08-20)
    • Concepts and Techniques of Dendrochronology

      Ferguson, C. W.; Laboratory of Tree-Ring Research, University of Arizona (Laboratory of Tree-Ring Research, University of Arizona (Tucson, AZ), 1970)
    • Conditional Probability of Occurrence for Variations in Climate Based on Widths of Annual Tree Rings in Arizona

      Stockton, Charles W.; Fritts, Harold C.; Laboratory of Tree-Ring Research, University of Arizona; Laboratory of Tree-Ring Research, University of Arizona (Laboratory of Tree-Ring Research, University of Arizona (Tucson, AZ), 1968-01-10)
      Modern statistical innovations have been incorporated into several recent analyses of tree -ring growth as related to climate. For example, Fritts (1962) used stepwise multiple regression techniques to study the systematic relationship of ring widths to climatic parameters in the southwestern United States; Bryson and Dutton (1962) have utilized power and cross -power spectral analyses in analyzing tree-ring records for periodicities; Mitchell (1967) applied factorial analysis; and Julian and Fritts (1967) introduced digital filter techniques as a means of appraising the systematic relations of tree growth to climatic variables. None of these studies, however, has attempted to analyze the joint occurrence of specific ring widths with certain climatic types so that probability statements could be made about climate from ring widths. This present study analyzes the joint occurrence of climate and relative width of tree rings for the state of Arizona. Conditional probabilities of occurrence are used to establish quantitative relevance of state -wide tree -ring growth from 1900 through 1957 to recorded climate for 1899 through 1957. The results are then used to make probability estimates of climate for the period 1650 through 1899.
    • Cutoff Lows in the Southwestern United States and Their Effects on the Precipitation of this Region: A Study of Circulation Features that may be Recorded by Tree Rings

      Douglas, Arthur V.; Laboratory of Tree-Ring Research, University of Arizona (Laboratory of Tree-Ring Research, University of Arizona (Tucson, AZ), 1974-06)
    • Dendrochronological and Paleoecological Evidence for Holocene Climatic Fluctuations in the White Mountains, California

      LaMarche, Valmore C., Jr.; Laboratory of Tree-Ring Research, University of Arizona (Laboratory of Tree-Ring Research, University of Arizona (Tucson, AZ), 1974-05-20)
      The bristlecone pines are of exceptional interest for studies of past environmental changes and especially of climatic changes. Individual trees of these species attain ages approaching 5000 years, and the wood of dead trees can remain intact for several thousand years more. These characteristics permit the development of very long tree-ring chronologies. Furthermore, ecological and environmental changes are shown by the age structure of the forest and by presence of logs, stumps, and wood remnants in areas that are now unforested. The Great Basin bristlecone pine (Pinus longaeva D. K. Bailey) and the closely related Rocky Mountain bristlecone pine (P. aristata Engelm.) are widely distributed in the high mountains of western United States. However, the largest number of old trees and the greatest climatic sensitivity of ring -width characteristics and of distributional patterns are found at the western limits of the Great Basin species - in the White Mountains of eastern California.
    • Dendrochronology in Mexico

      Bannister, Bryant; Scott, Stuart D.; Laboratory of Tree-Ring Research, University of Arizona (Laboratory of Tree-Ring Research, University of Arizona (Tucson, AZ), 1964)
    • Dendrochronology of Bristlecone Pine in East-Central Nevada

      Ferguson, C.W.; Laboratory of Tree-Ring Research, University of Arizona (Laboratory of Tree-Ring Research, University of Arizona (Tucson, AZ), 1970-06-30)
      In the Administrative Study Plan, as set forth 10 August 1966 and approved 16 August 1966, it was proposed that a joint inventory and dendrochronological study of bristlecone pine, Pinus aristata Engelm., be conducted by the Forest Service and the University of Arizona on the Snake, Mt. Moriah, Ward Mountain, and the Schell Creek divisions of the Humboldt National Forest in Nevada. Through a closely integrated inventory and dendrochronological program designed to take full advantage of the unique scientific resources available at the University of Arizona, the proposed study was expected to yield maximum information on the age, volume, growth, extent, and area of bristlecone pine and to provide authoritative data for interpretive and future planning uses. Dr. J. O. Klemmedson of the Department of Watershed Management, for the inventory phase, and Dr. C. W. Ferguson of the Laboratory of Tree -Ring Research, for the dendrochronological phase, were co- investigators of the project.
    • Dendrochronology of Bristlecone Pine Prior to 4000 B.C.

      Ferguson, C. W.; Laboratory of Tree-Ring Research, University of Arizona (Laboratory of Tree-Ring Research, University of Arizona (Tucson, AZ), 1972-10)
      A 7104 -year tree -ring chronology for bristlecone pine was published in tabular form in 1969. Since then, the chronology has been improved in quality and extended in time. Twenty-one pieces of wood, representing separate trees, have been identified for the period prior to 4000 B.C. and these have made possible a chronology extension to nearly 8200 years. In this paper, the specimens are described in terms of the time range each represents and their statistical parameters relating to the quality of tree-ring record they contain. These specimens not only have extended the climatic tree-ring chronology, but also have made possible the calendar-year dating of additional samples for calibration of the radiocarbon time scale.
    • Dendrochronology on and Adjoining the Appleton-Whittell Research Ranch

      Ferguson, C. W.; Laboratory of Tree-Ring Research, University of Arizona (Laboratory of Tree-Ring Research, University of Arizona (Tucson, AZ), 1983-03-11)
    • Diagnosis and Distribution of Conifer Decay in the Swiss Rhone Valley: A Dendrochronological Study

      Schweingruber, F. H.; Kontic, R.; Niederer, M.; Nippel, C. A.; Winkler-Seifert, A.; Swiss Federal Institute of Forestry Research, Birmensdorf, Switzerland; Institute of Botany, University, Basel, Switzerland (Laboratory of Tree-Ring Research, University of Arizona (Tucson, AZ), 1985)
      Abrupt, long -term growth reductions evident in annual ring sequences were visually identified and dated. The simple method used allowed relationship of the frequency of such reductions to site and industry. In the Valais, the first damage occured as early as 1921, with the greatest damage concentrated in the early seventies. From 1977 onwards, recovery is apparent in annual ring sequences from the Valais but not from the Swiss Mittel-land. No clear relationships between abrupt growth reduction and site or climate were found. Annual ring analysis indicates local and regional pollution as the cause of the reductions.
    • Drought History and Reconstructions from Tree Rings

      Stockton, Charles W.; Meko, David M.; Boggess, William R.; Laboratory of Tree-Ring Research, University of Arizona; Laboratory of Tree-Ring Research, University of Arizona; Laboratory of Tree-Ring Research, University of Arizona (Laboratory of Tree-Ring Research, University of Arizona (Tucson, AZ), 1989-07)
    • Estimating Long-Term Statistics for Annual Precipitation for Six Regions of the United States from Tree-Ring Data

      Fritts, Harold C.; DeWitt, Emily; Gordon, Geoffrey A.; Hunt, John H.; Lofgren, G. Robert; Laboratory of Tree-Ring Research, University of Arizona; Laboratory of Tree-Ring Research, University of Arizona; Laboratory of Tree-Ring Research, University of Arizona; Laboratory of Tree-Ring Research, University of Arizona; Laboratory of Tree-Ring Research, University of Arizona (Laboratory of Tree-Ring Research, University of Arizona (Tucson, AZ), 1979-12)
      Spatial anomalies of seasonal precipitation for the United States and southwestern Canada have been reconstructed from 1602 through 1961 using dendrochronologicai and multivariate techniques on 65 arid-site tree-ring chronologies from western North America. Seasonal reconstructions are averaged to obtain mean annual precipitation values for six regions of importance to the Nuclear Regulatory Commission (NRC) Nuclear Waste Management Program (NWMP). Statistics calculated from the regionally averaged annual values for 25-year and longer intervals show annual precipitation in the seventeenth through nineteenth centuries to be lower than in the twentieth century for three regions in the American Southwest and higher for one region in the Northwest and two regions in the East. The variability of precipitation generally was higher in the past three centuries than in the present century. Twenty-five-year intervals with noteworthy statistics are identified and important results are summarized and tabulated for use in the hydrologic modeling of the NWMP. Additional research is recommended to incorporate temperature and precipitation into a single hydrologic parameter.
    • An Examination of the Possible Causes of Climatic Variations Revealed in Well-Verified Dendroclimatic Reconstructions for North America and the North Pacific: Final Project Report

      Fritts, H. C.; Lough, J. M.; Laboratory of Tree-Ring Research, University of Arizona; Laboratory of Tree-Ring Research, University of Arizona (Laboratory of Tree-Ring Research, University of Arizona (Tucson, AZ), 1984-12)
    • Fire History in Ponderosa Pine and Mixed-Conifer Forests of the Jemez Mountains, Northern New Mexico

      Touchan, Ramzi; Swetnam, Thomas W.; Laboratory of Tree-Ring Research, University of Arizona; Laboratory of Tree-Ring Research, University of Arizona (Laboratory of Tree-Ring Research, University of Arizona (Tucson, AZ), 1995-03-20)
      We reconstructed fire history in ponderosa pine and mixed-conifer forests across the Jemez Mountains in northern New Mexico. We collected the fire-scarred samples from nine ponderosa pine areas and four mesic mixed-conifer areas. An additional collection was obtained from a bristlecone pine stand in the Sangre de Cristo Mountains. We also reconstructed December-June precipitation from ponderosa pine tree-ring indices that were developed from four different watersheds in northern New Mexico. Prior to 1900, ponderosa pine forests were characterized by high frequency, low intensity surface fire regimes. The mixed-conifer stands sustained somewhat less frequent surface fires, along with patchy crown fires. In both ponderosa pine and mixed-conifer forests precipitation was significantly reduced in the winter-spring seasons preceding fire events. In addition, winter-spring precipitation during the third year preceding major fire years in the ponderosa pine forest was significantly increased. This study provides baseline knowledge concerning the ecological role of fire in ponderosa pine and mixed-conifer forests. This information is vital to support ongoing ecosystem management efforts in the Jemez Mountains.