Thomas W. Swetnam

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Thomas W. Swetnam (born 1955) is Regents' Professor Emeritus of Dendrochronology at the University of Arizona, studying disturbances of forest ecosystems across temporal and spatial scales. He served as the Director of the Laboratory of Tree-Ring Research [1] from 2000 to 2015.

Dendrochronology method of dating based on the analysis of patterns of tree rings

Dendrochronology is the scientific method of dating tree rings to the exact year they were formed. As well as dating them this can give data for dendroclimatology, the study of climate and atmospheric conditions during different periods in history from wood.

University of Arizona public university in Tucson, Arizona, United States

The University of Arizona is a public research university in Tucson, Arizona. Founded in 1885, the UA was the first university in the Arizona Territory. As of 2017, the university enrolls 44,831 students in 19 separate colleges/schools, including the University of Arizona College of Medicine in Tucson and Phoenix and the James E. Rogers College of Law, and is affiliated with two academic medical centers. The University of Arizona is governed by the Arizona Board of Regents. The University of Arizona is one of the elected members of the Association of American Universities and is the only representative from the state of Arizona to this group.



Swetnam received his bachelor's degree in biology and chemistry from the University of New Mexico and subsequently received his master's and PhD from the University of Arizona in watershed management and dendrochronology.

University of New Mexico public research university in Albuquerque, New Mexico, United States

The University of New Mexico is a public research university in Albuquerque, New Mexico. Founded in 1889, UNM offers bachelor's, master's, doctoral, and professional degree programs in multiple fields. Its Albuquerque campus encompasses over 600 acres (2.4 km²), and there are branch campuses in Gallup, Los Alamos, Rio Rancho, Taos, and Los Lunas. UNM is categorized as an R1 doctoral university in the Carnegie Classification of Institutions of Higher Education

Watershed management is the study of the relevant characteristics of a watershed aimed at the sustainable distribution of its resources and the process of creating and implementing plans, programs, and projects to sustain and enhance watershed functions that affect the plant, animal, and human communities within the watershed boundary. Features of watershed that agencies seek to manage include water supply, water quality, drainage, stormwater runoff, water rights, and the overall planning and utilization of watersheds. Landowners, land use agencies, stormwater management experts, environmental specialists, water use surveyors and communities all play an integral part in watershed management.


He received the A.E. Douglass award from the University of Arizona, the W.S. Cooper award from the Ecological Society of America (with Julio Betancourt) and the Henry Cowles award from the American Association of Geographers (with James H. Speer). He was elected a Fellow of the American Association For the Advancement of Science in 2015. He received the Harold C. Fritts Lifetime Achievement Award from the Tree-Ring Society in 2016.

Henry Chandler Cowles American botanist

Henry Chandler Cowles was an American botanist and ecological pioneer. A professor at the University of Chicago, he studied ecological succession in the Indiana Dunes of Northwest Indiana. This led to efforts to preserve the Indiana Dunes. One of Cowles' students, O. D. Frank continued his research.

American Association of Geographers organization

The American Association of Geographers (AAG) is a non-profit scientific and educational society aimed at advancing the understanding, study, and importance of geography and related fields. Its headquarters are located at 1710 16th St NW, Washington, D.C. The organization was founded on 29 December 1904 in Philadelphia as the Association of American Geographers, with the American Society of Professional Geographers later amalgamating into it in December 1948 in Madison, 1025 Currently, the association has more than 10,000 members from over 60 countries. AAG members are geographers and related professionals who work in the public, private, and academic sectors.

James H. Speer is a professor of geography and geology at Indiana State University. He is a past president of the Tree-Ring Society and the Geography Educator's Network of Indiana. He has been the organizer for the North American Dendroecological Fieldweek (NADEF) since 2003.


He has served on the following advisory and editorial boards:

Board of Trustees, Valles Caldera National Preserve (2000-2004); Arizona Forest Health Advisory Council (2003-2006); Arizona Climate Change Advisory Group (2005-2006); Associate Editor, International Journal of Wildland Fire, (1993–present); Editor, Tree-Ring Research (2000-2001); Associate Editor, Ecoscience (1994-1998); Associate Editor, Canadian Journal of Forest Research (1998); Editorial Board, Ecological Applications (1998-1999); Associate Editor, Dendrochronlogia, (2005–2012); Board of Trustees, The Nature Conservancy, New Mexico, 2016–present.


He has authored and co-authored approximately more than 120 scientific papers in journals and symposium proceedings, including the following frequently cited/significant papers:

The bibcode is a compact identifier used by several astronomical data systems to uniquely specify literature references.

Digital object identifier Character string used as a permanent identifier for a digital object, in a format controlled by the International DOI Foundation

In computing, a Digital Object Identifier or DOI is a persistent identifier or handle used to uniquely identify objects, standardized by the International Organization for Standardization (ISO). An implementation of the Handle System, DOIs are in wide use mainly to identify academic, professional, and government information, such as journal articles, research reports and data sets, and official publications though they also have been used to identify other types of information resources, such as commercial videos.

JSTOR subscription digital library

JSTOR is a digital library founded in 1995. Originally containing digitized back issues of academic journals, it now also includes books and other primary sources, and current issues of journals. It provides full-text searches of almost 2,000 journals. As of 2013, more than 8,000 institutions in more than 160 countries had access to JSTOR; most access is by subscription, but some of the site's public domain and open access content is available at no cost to anyone. JSTOR's revenue was $86 million in 2015.

Edited books

International Standard Book Number Unique numeric book identifier

The International Standard Book Number (ISBN) is a numeric commercial book identifier which is intended to be unique. Publishers purchase ISBNs from an affiliate of the International ISBN Agency.

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William F. Laurance is Distinguished Research Professor at James Cook University, Australia and has been elected as a Fellow of the Australian Academy of Science. He has received an Australian Laureate Fellowship from the Australian Research Council. He also has holds the Prince Bernhard Chair for International Nature Conservation at Utrecht University, Netherlands.

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Thomas Thorstein Veblen is an American forest ecologist and physical geographer known for his work on the ecology of Nothofagus forests in the Southern Hemisphere and on the ecology of conifer forests in the southern Rocky Mountains of the U.S.A. He is an Arts and Sciences College Professor of Distinction at University of Colorado at Boulder, USA (2006).