Scott St. George
Paleoclimatology | Dendrochronology | Hazards
I am an Associate Professor of Geography, Environment and Society, and Institute on the Environment Fellow at the University of Minnesota. I'm also an Adjunct Assistant Professor in the School of Environmental Sciences at Queen’s University (Canada), and a Humboldt Research Fellow at the Alexander von Humboldt Foundation (Germany).
As an earth scientist trained in paleoclimatology,I use evidence preserved in geological or biological archives to understand how and why our environment has changed during the last several hundred or thousands of years. By extending our perspective beyond the most recent century, my research provides a long-term benchmark to test ideas about the underlying causes of environmental change and the likely future trajectories of critical environmental systems, particularly those aspects related to forests, climate change, and surface hydrology.
My research team has produced new paleoclimate records from Minnesota, California, and Oregon, and has combined empirical and modeling approaches to map the influence of climate on tree growth in forests across the Northern Hemisphere, and evaluate how trees respond to (or ignore) the influence of particular climatic and non-climatic factors. My colleagues and I have identified regions where decadal and multidecadal behavior within the climate system is particularly important, used proxy networks to estimate its progression during the past several centuries, and critically assessed the ability of current-generation climate models to simulate this particular ‘flavor’ of climate change. Overall, this research has produced new insights into how atmospheric, ecological, and geological systems act and interact, and has made communities more resilient to the impacts of climate change and natural hazards.
Previously, I was a Research Scientist in the Geological Survey of Canada at Natural Resources Canada. I received my doctorate in geosciences from the University of Arizona, where I was affiliated with the Department of Geosciences and the Laboratory of Tree-Ring Research. I hold an M.Sc. in Geography from the University of Western Ontario and a B.Sc. in Geography from the University of Winnipeg.
During the 2016-17 academic year, I will be on sabbatical (research leave) and off campus and out-of-country. Early in 2017, I will be a visiting scientist at the Johannes Gutenberg-Universität Mainz and Helmholtz-Zentrum Geesthacht in Germany.
Announcements & news
Short blurbs on our latest products, upcoming meetings, and research opportunities at the University of Minnesota's Center for Dendrochronology.
A global multiproxy database for temperature reconstructions of the Common Era
PAGES 2k Consortium. Scientific Data (in preparation).
Tree growth across the Nepal Himalaya during the last four centuries
Udya Thapa, Scott St. George
Forward modeling of tree-climate relations across the Northern Hemisphere
Xiaolu Li, Scott St. George, Kevin J. Anchukaitis.
Tree-climate relations along an elevational transect in Manang Valley, central Nepal
Deepak K. Kharal, Udya K. Thapa, Scott St. George, Henrik Meilby, Santosh Rayamajhi, Dinesh R. Bhuju, Dendrochronologia (in press) [DOI]
Making climate data sing — Using music-like sonifications to convey a key climate record
Scott St. George, Daniel Crawford, Todd Reubold, Elizabeth Giorgi, The Bulletin of the American Meteorological Society (in press) [DOI]
On the AD 1815 Tambora eruption and the matter of misplaced tree rings
Scott St. George, Kevin J. Anchukaitis, Past Global Changes Magazine 23, 2015 [PDF]
A review of flood records
from tree rings
Juan Antonio Ballesteros-Cánovas, Markus Stoffel, Scott St. George, Katherine A. Hirschboeck, Progress in Physical Geography, 2015 [DOI]
Flooding, structural flood control measures, and recent geomorphic research along the Red River, Manitoba, Canada
Greg R. Brooks, Scott St. George, In Geomorphology and Management of Embanked Floodplains: North American and European Fluvial Systems in a Era of Global Environmental Change. Springer, 2015 [DOI]
New ages for shoreline stumps along Lake Winnipeg, Canada and their implications for paleo-lake level estimates
Scott St. George, Max C.A. Torbenson, The Holocene 24, 1393-1397, 2014 [DOI]
An overview of tree-ring width records across the Northern Hemisphere
Scott St. George, Quaternary Science Reviews 95, 132-150, 2014 [DOI]
The global network of tree-ring widths and its applications to paleoclimatology
Scott St. George, Past Global Changes Magazine 22, 16-17, 2014 [PDF]
The imprint of climate within Northern Hemisphere trees
Scott St. George, Toby Ault, Quaternary Science Reviews 89, 1-4, 2014 [DOI].
The continuum of hydroclimate variability in western North America during the last millennium
Toby R. Ault, Julia E. Cole, Jonathan T. Overpeck, Gregory T. Pederson, Scott St. George, Bette Otto-Bliesner, Connie A. Woodhouse, Clara Deser, Journal of Climate 26, 5863-5878, 2013 [DOI]
The rarity of absent growth rings in Northern Hemisphere forests outside the American Southwest
Scott St. George, Toby R. Ault, Max C.A. Torbenson, Geophysical Research Letters 40, 2013 [DOI]
Vessel anomalies in Quercus macrocarpa tree rings associated with recent major floods along the Red River of the North, United States
Erika L. Wertz, Scott St. George, Joseph D. Zeleznik, Water Resources Research 49, 630-634, 2013 [DOI]
The amplitude of decadal to multidecadal variability in precipitation simulated by state-of-the-art climate models
Toby R. Ault, Julia E. Cole, Scott St. George, Geophysical Research Letters 39, L21705, 2012 [DOI]
Does proxy uncertainty affect the relations inferred between the Pacific Decadal Oscillation and wildfire activity in the western United States?
Kurt F. Kipfmueller, Evan R. Larson, Scott St. George, Geophysical Research Letters 39, L04703, 2012 [DOI]
Is energetic decadal variability a stable feature of the central Pacific Coast's winter climate?
Scott St. George, Toby R. Ault, Journal of Geophysical Research - Atmospheres 116, D12102, 2011 [DOI]
The seasonality of precipitation signals embedded within the North American Drought Atlas
Scott St. George, David M. Meko, Edward R. Cook, The Holocene 20, 983-988, 2010 [DOI]
Tree rings as paleoflood and paleostage indicators
Scott St. George, In Stoffel, M., Bollschweiler, M., Butler, D.R., Luckman, B.H (editors), Tree-ring reconstructions in natural hazards research: a state-of-the-art. Advances in Global Change Research series. Springer. p. 233-240, 2010 [PDF]
Current and past students
I advise students enrolled in the M.A. and Ph.D. programs in Geography and am able to serve on graduate committees for students completing other degree programs at the University of Minnesota. Our graduate students have won several departmental and university-level awards, presented at major national meetings, including the Association of American Geographers and the American Geophysical Union, and graduating M.A. students have secured places within highly-regarded doctoral programs in the geosciences.
Uday Kunwar Thapa
Ph.D. in Geography (in progress)
Dissertation title: Evaluating the magnitude and causes of climate and hydrological variability across the Nepalese Himalaya during the last several centuries
Xinran (Julina) Duan
B.Sc. in Mathematics (in progress)
Undergraduate research project: Quantifying long-term trends in the Red River of the North
B.Sc. in Geography, 2016
Undergraduate research project: Climate variability and its relationship with air travel times in the Seattle-Minneapolis corridor
B.Sc. in Geography, 2015
Undergraduate research project: Expressing global temperature change through music
M.A. in Geography, 2015
Thesis title: Mountain hemlock (Tsuga mertensiana) growth and cool-season precipitation in Crater Lake National Park, Oregon
B.Sc. in Plant Biology, 2014
Directed research project: Growth boundaries of Swietenia macrophylla and Cedrela odorata from a subtropical dry forest in Guanacaste, Costa Rica and their potential application in dendrochronology
Xiaolu (Grace) Li
M.A. in Geography, 2014
Thesis title: Assessing forward modeling of tree-ring growth and the impacts of non-climatic factors on tree-ring width in the Northern Hemisphere
M.A. in Geography, 2013
Thesis title: Assessing the response of upper montane forests to decadal variability in winter precipitation
B.Sc. (Honors) in Geography, 2012
Thesis title: Testing whether vessel characteristics in bur oak can serve as proxies for severe Red River floods within the United States
I regularly lecture on climate change, water resources, tree rings, and scientific presentations. Visual aids for some of my recent talks are available to view online at Slideshare.
Trees as flood sensors
Future paleoflood research involving tree rings will need to strike a balance between improving our understanding of the biological and fluvial processes that link tree growth to past events, and providing answers to questions about flood dynamics and hazards that are needed to safeguard people and property from future floods.
Expanding the window - the past, present, and future of Minnesota's water
The Water Supply Convergence Colloquium offers a targeted opportunity to participate in a facilitated discussion about how research and collaboration can help advance productive and sustainable planning and management of our water supply.
Making climate data sing
Music is inherently narrative and is known to exert a powerful influence on human emotions. Here we report on a collaboration between scientists and artists at the University of Minnesota that uses data sonification with added musical elements to transmit the evidence of climate change in an engaging and visceral way.
Large-scale dendrochronology and low-frequency climate variability
As the leading source of high-resolution paleoclimate information in the middle- and high-latitudes, tree rings are essential to understand low-frequency variability prior to the instrumental period. In this lecture, Dr. St. George describes the structure and characteristics of the Northern Hemisphere tree-ring width network, and outlines how the fingerprint of decadal and multidecadal climate variability encoded within ancient trees varies across the hemisphere.
Noah, Joseph, and high-resolution paleoclimatology
In 1968, Benoit Mandelbrot and James Wallis published an article titled ‘Noah, Joseph, and operational Hydrology’ in the journal Water Resources Research. In it, they argued that hydrological models of the day were not able to estimate the true risk of extreme floods or prolonged drought, and that rare hydrological events were much more common than usually assumed. In this lecture, I’ll review how high-resolution paleoenvironmental archives can help us judge more accurately the risks posed by the ‘Noah’- and ‘Joseph’-style events described by Mandelbrot and Wallis.
Guarding against false discovery in large-scale dendrochronology
Measurements of tree-ring widths are the most widely-distributed and best replicated source of surrogate environmental information on the planet, and are one of the main archives used to estimate changes in regional and global climate during the past several centuries or millennia. Because the Northern Hemisphere ring-width network is now so large, it is more crucial than ever to ensure our understanding of tree-environment relations is not influenced by decisions to include or exclude certain records.
A Song of Our Warming Planet: Using music to communicate critical concepts in climate science
When climate science is communicated to the broader public, many of its key findings are shared in the form of conceptual diagrams or information-dense data graphics. In this collaboration, we applied a data sonification approach to express NASA’s global temperature record as a musical composition for the cello.
The "Year Without A Summer" was not a year without a ring
The Tambora eruption of 1815 cooled the planet and caused the "Year Without A Summer" in western Europe and eastern North America. But was it cold enough to cause trees across the Northern Hemisphere to skip a ring?
Seeing the forest for the tree(ring)s
In this lecture, I describe the structure and characteristics of the Northern Hemisphere tree-ring width network, and outline how these data are linked with key aspects of local climate and the global climate system.
The decadal character of northern California's winter precipitation
Starting in the 1930s, northern California has experienced major decade-to-decade swings in the amount of precipitation that falls during winter. Is this behavior the product of a physical mechanism that favors fluctuations at decadal time scales or is it simply a result of stochastic variability in the climate system?
Through the trees: How tree rings can help us understand environmental change in Minnesota
Whether we're setting limits for the use of scarce resources, estimating the risks posed by natural hazards, or deciding how to manage protected areas, our plans for the future often reflect our understanding of the past. The problem is that, when it comes to the environment, our society has a fairly short memory.
El Niño stills winter winds across the southern Canadian Prairies
Analysis of long-term terrestrial wind speed (u) records demonstrates that interannual variability is a major component of near-surface wind dynamics in the southern Canadian Prairies. Wind energy facilities in the SCP have been built during a period of relatively stable wind conditions, and the next El Niño may test their ability to maintain expected energy outputs.
At the undergraduate level, I teach advanced classes in dendrochronology (which uses annual growth rings in trees to understand how our environment has behaved in the past) and Holocene paleoclimatology (focused on the evolution of Earth’s climate since the end of the last ice age), as well as an introductory course in biogeography.
I also offer graduate courses in paleoclimatology, climatology, and science communication, and supervises graduate students conducting research on water resources, decade-to-centennial scale climate variability, and hemispheric-scale dendroclimatology.
When science is communicated to the broader public, many of its key findings are shared in the form of dense prose, conceptual diagrams or information-dense data graphics. Although those tools can be effective, they do not always offer the best way to reach every audience.
Based on surface temperature analysis from NASA’s Goddard Institute for Space Studies, the composition 'Planetary Bands, Warming World' uses music to create a visceral encounter with more than a century’s worth of weather data collected across the northern half of the planet.
With support from the University of Minnesota’s School of Music and its Institute on the Environment, in 2012 Dr. St. George began a collaborative project using music to communicate critical concepts in climate science. The first product from this collaboration was a piece written by an undergraduate student in Geography that expressed NASA’s global temperature record as a musical composition for the cello. The result, which was titled ‘A Song of Our Warming Planet’, transformed 133 years of annual global temperature anomalies into a haunting, atonal melody that stretched across almost all of the instrument’s range. Since its release in June 2013, ‘A Song of Our Warming Planet’ has been featured by several national and international media outlets, including the New York Times, the Weather Channel, and National Public Radio, and its accompanying video has received more than 140,000 views from nearly every corner of the world. Because the composition was released under a Creative Commons license, it has been performed (and in some cases, reinterpreted) by local and international artists, including musicians from Wisconsin, California, New York, Canada, and the Netherlands.
The ability to deliver effective and engaging oral presentations is a critical skill for scholars in all disciplines. Unfortunately, despite the importance of clear communication, professional presentations about research are too often confusing, abstract and boring. In this video, Dr. St. George outlines five small changes you can make to become a more effective communicator.