Malcolm Hughes

Regents' Professor Emeritus


I have focused on contributing to the building of large scale (continental to global) networks of “proxy” climate records with defined chronology, temporal resolution and climate signal. In support of this general aim I work to:

  1. establish new kinds of tree ring record (new species, new regions, new variables) that may be used, in combination with other records, to “thencast” the behavior of the climate system. Recently I have mainly cooperated Drs. Matthew Salzer (LTRR), Andy Bunn (Western Washington University) and Kurt Kipfmueller (University of Minnesota and other colleagues on the expansion, enhancement and updating of millennial and multimillennial chronologies of bristlecone pine and its congeners. I continue to work on hemispheric and global climate reconstructions.

  2. use climate reconstructions or “thencasts” to raise questions about the behavior of the climate system. These questions not only apply to the nature of the 20th century in comparison to earlier periods, but also to the potential existence of multimillennial “regimes” at the scale of the Pacific Basin and perhaps on even larger scales.

  3. base this on improved understanding of the mechanisms controlling tree-ring variability, primarily in collaboration with Academician Eugene Vaganov of the Russian Academy of Sciences, Dr. Michael Evans (University of Maryland) and Dr. Kevin Anchukaitis (University of Arizona). The prime focus of our collaboration has been the further development and testing of a model of the environmental control of tree-ring formation. A separate model for the simulation of tree-ring chronology building and the detection of time-dependent biases in tree-ring chronologies has been under development with Dr. Kurt Kipfmueller of the University of Minnesota.
  4. explore the uses of tree rings along with remotely-sensed data to place recent fluctuations or changes in forest growth in a multidecadal to centennial time perspective.






NSF CMG Program. CMG Collaborative Research: Development of Bayesian Hierarchical Models to reconstruct climate over the past millennium. Michael N Evans (PI) and Malcolm K Hughes (co-PI). (Funded 2007)

NSF Paleoclimatology Program. Late Holocene Hydroclimate variability in the Great Basin, and its causes. Malcolm K Hughes (PI) and Matthew W. Salzer (co-PI).  (Funded 2009)

NASA LCLUC program Response of forest growth to climate variability and change: remotely-sensed and in-situ data for European Russia. Malcolm K Hughes (PI) and Andy Bunn (Western Washington University, co-PI).  (Funded 2009)

NSF P2C2 program: Collaborative research: Quantifying climate thresholds for high elevation pines using landscape heterogeneity to improve climate reconstructions from tree rings. Mathew W Salzer, PI, Malcolm K Hughes, co-PI.  – collaborators Andrew G. Bunn, Western Washington University and Stuart B. Weiss, Creekside Center for Earth Observation. (Funded 2012)

NSF P2C2 program: Growth Dynamics in the Climate Control of Tree-Ring Variability for Paleoclimatology. Malcolm K Hughes, PI (collaborator Peter M Brown, Rocky Mountain Tree-Ring Research). (Funded 2014)

NSF Collaborative proposal: Forest carbon-water interactions in relation to the North American Monsoon climate system. Russell Monson, PI, Jia Hu and Malcolm Hughes, co-PIs). (Funded 2018)



You can find most of my publications on my Google Scholar profile. Here are my publications from 2009 on:


158.  Hughes, MK, Olchev, A., Bunn, A.G., Berner, L.T., Losleban, M. and Novenko, E.: Different climate responses of spruce and pine growth in northern European Russia. Dendrochronologia 56,*


157. Churakova (Sidorova), O. V., Fonti, M. V., Saurer, M., Guillet, S., Corona, C., Fonti, P., Myglan, V. S., Kirdyanov, A. V., Naumova, O. V., Ovchinnikov, D. V., Shashkin, A. V., Panyushkina, I. P., Büntgen, U., Hughes, M. K., Vaganov, E. A., Siegwolf, R. T. W., and Stoffel, M.: Siberian tree-ring and stable isotope proxies as indicators of temperature and moisture changes after major stratospheric volcanic eruptions, Clim. Past, 15, 685-700,,*.



156. Bunn, A.G., Salzer, M.W., Anchukaitis, K.J., Bruening, J.M. and Hughes, M.K. Spatiotemporal Variability in the Climate Growth Response of High Elevation Bristlecone Pine in the White Mountains of California. Geophysical Research Letters, DOI: 10.1029/2018GL080981 ()*


155. Panyushkina, IP, Shishov, VV, Grachev, AM, Knorre, AA, Kirdyanov, AV, Leavitt, SW, Vaganov, EA, Chebykin, E, Zhuchenko, NA, Hughes, MK. Trends in elemental concentrations of tree rings from the Siberian Arctic. Tree-Ring Research 72 (2), 67-77 *


154. Tolwinski-Ward, S.E., Tingley, M.P., Evans, M.N., Hughes, M.K., Nychka, D.W. Probabilistic reconstructions of local temperature and soil moisture from tree-ring data with potentially time-varying climatic response. Climate Dynamics DOI 10.1007/s00382-014-2139-z*


153. Salzer, M.W., Larson, E.R. Bunn, A.G. and Hughes, M.K. Changing climate response in near-treeline bristlecone pine with elevation and aspect. Environmental Research Letters DOI:10.1088/1748-9326/9/11/114007*

152. Churakova, O.V., Bryukhanova, M.V., Saurer, M., Boettger, T. Naurzbaev, M.M, Myglan, V.S., Vaganov, E.A., Hughes, M.K. and Siegwolf, R.T.W. A cluster of stratospheric volcanic eruptions in the AD 530s recorded in Siberian tree rings. Global and Planetary Change DOI:10.1016/j.gloplacha.2014.08.015*



151. Bunn, A.G., Hughes, M.K., Kirdyanov, A.V., Losleben, M., Shishov, V.V., Berner, L.T., Oltchev, A. and Vaganov, E.A.. Comparing forest measurements from tree rings and a space-based index of vegetation activity in Siberia. Environmental Research Letters DOI:10.1088/1748-9326/8/3/035034*

150. Salzer, M.W., Bunn, A.G., Graham, N.E., and Hughes, M.K. Five millennia of paleotemperature from tree rings in the Great Basin, USA. Climate Dynamics DOI 10.1007/s00382-013-1911-9*


149. von Arx, G., Archer, S.A., Hughes, M.K. Long-term functional plasticity in plant hydraulic architecture in response to supplemental moisture. Annals of Botany 108: 1091-1100.*    

148. Anchukaitis, K.J. Breitenmoser, P., Briffa, K.R., Buchwal, A., Büntgen, U., Cook, E.R., D'Arrigo, R., Esper,J., Evans, M.N., Frank, D., Grudd, H., Gunnarson, B.E, Hughes, M.K., Kirdyanov, A.V., Körner, C., Krusic, P.J., Luckman, B., Melvin, T.M.,  Salzer, M.W., Shashkin, A.V., Timmreck, C., Vaganov E.A. & Wilson, R.J.S.. Tree rings and volcanic cooling. Nature Geoscience 5: 836-837*



147. Diaz, H.F., Trigo, R., Hughes, M.K., Mann, M.E., Xoplaki, E. and Barriopedro, D. Spatial and temporal characteristics of climate in medieval times revisited. Bulletin of the American Meteorological Society.  DOI:10.1175/BAMS-D-10-05003.1*

146. Bunn, A.G., Hughes, M.K. and Salzer, M.W. Topographically Modified Tree-Ring Chronologies as a Potential Means to Improve Paleoclimate Inference. Climate Change Letters. 105: 627-634*



145. Tolwinski-Ward, S., Evans, M.N., Hughes, M.K. and Anchulaitis, K.J. An Efficient Forward Model of the Climate Controls on Interannual Variation in Tree-Ring Width. Climate Dynamics. DOI 10.1007/s00382-010-0945-5*

144. Hughes, M.K., Guiot, J. and Ammann., C.M. An emerging paradigm: process-based climate reconstructions. PAGES Newsletter. Volume 18, number 2. pp 87-89 (2010)

143.Villalba, R. and 30 others, including M.K. Hughes. Dendroclimatology from regional to continental scales: Understanding regional processes to reconstruct large-scale climatic variations across the Western Americas. In: Hughes, MK, Swetnam, TW and Diaz, HF, (editors) Dendroclimatology: Progress and Prospects. (Springer Verlag). pp 175-227 (2011) @

142. Hughes, M.K., Diaz, H.F. and Swetnam, T.W. Tree Rings and Climate: Sharpening the Focus. In: Hughes, MK, Swetnam, TW and Diaz, HF, (editors) Dendroclimatology: Progress and Prospects. (Springer Verlag). pp 331-353 (2011) @

141. Hughes, M.K. Dendroclimatology in High-Resolution Paleoclimatology. In: Hughes, MK, Swetnam, TW and Diaz, HF, (editors) Dendroclimatology: Progress and Prospects. (Springer Verlag). pp 17-36 (2011) @

140. Hughes, M.K., Swetnam, T.W. and Diaz, H.F. (editors) Dendroclimatology: Progress and Prospects. (Springer Verlag). xii + 365pp. (2011) #



139. Mann, M.E., Zhihua Zhang, Rutherford S, Bradley, R.S., Hughes, M.K. Shindell, D.,  Ammann, C., Faluvegi, G., Fenbiao Ni. Global Signatures and Dynamical Origins of the “Little Ice Age” and “Medieval Climate Anomaly”.  Science. 326: 1256-1260 (2009)*

138. Salzer, M.W., Hughes, M.K., Bunn, A. and Kipfmueller, K. F. Recent unprecedented tree-ring growth in bristlecone pine at the highest elevations and possible causes. Proceedings of the National Academy of Science. doi: 10.1073/pnas.0903029106 (2009)*

137. Hughes, M.K. and Ammann, C.M. The future of the past—an earth system framework for high resolution paleoclimatology: editorial essay. Climatic Change, 94, 247-259 (2009).*


Key to symbols in list of publications

* refereed journal articles, # scholarly books, @ book chapters




Feeling the pulse of the planet (a class for honors freshmen)

Introduction to Dendrochronology (a graduate/upper division undergraduate class)

Practical dendroclimatology (an intensive class for graduate students and professionals)

Topics in dendrochronology (a graduate class)

Responsible conduct of environmental research (a graduate class)




1965                            B.Sc. (Honours) in Botany and Zoology, University of Durham, U.K..

1970                            Ph.D., title of thesis: 'Investigations of the ecosystem energetics of an English woodland'.  Supervisor; Dr. J. Phillipson, University of Durham.



1968-69     Amanuensis, Research Fellow, Soil Biology Institute, University of Aarhus, Denmark

1969-71     Postdoctoral Research Fellow, Botany Department,             University of Durham.

1971-73     Lecturer II in Ecology, Biology Department,,Liverpool Polytechnic (now Liverpool John Moores University).

1973-80     Senior Lecturer in Ecology, Liverpool Polytechnic.

1980-82     Principal Lecturer in Ecology, Liverpool Polytechnic.

1982-86     Reader in Palaeoecology, Liverpool Polytechnic.

1986-1999 Director of the Laboratory of Tree-Ring Research, University of Arizona

1986-         Professor of Dendrochronology, University of Arizona

1992-         Professor of Watershed Management, School of Renewable Natural Resources, University of Arizona

2007-         Regents’ Professor of Dendrochronology, University of Arizona.

2010-12     Honors Professor, Honors College, University of Arizona



1992-3        Visiting Fellow, Cooperative Institute for Research in Environmental Sciences, University of Colorado-Boulder

1998            Fellow, American Geophysical Union

1999-2000   Bullard Fellow, Harvard Forest, Harvard University

2006            Galileo Circle Fellow, University of Arizona

2007            Regents’ Professor, University of Arizona

2007-8         Visiting Fellow, Cooperative Institute for Research in Environmental Sciences, University of Colorado-Boulder     

2008            Visiting Faculty Fellow, National Center for Atmospheric Research.

2009            Elected Chair, Section E (Geology and Geography) American Association for the Advancement of Science (AAAS)

2013            Elected President, Global Environmental Change Focus Group, American Geophysical Union.

2014            Fellow, American Association for the Advancement of Science (AAAS)