LIA_pictureNovember 3-4, 2017 | Free and Open to the Public |

The Little Ice Age (LIA) is broadly defined as the time period from about 1250 to 1900 CE, the coldest centuries of the past 8000 years.  The causes of this cold interval are the subject of increasing interest to scientists, yet its effects on the people who lived through it are only beginning to be fully assessed. This conference brings together scholars who study climate forcings and climate change, as well as historians, archaeologists, and others who explore the human impact of the LIA.  We hope to advance understanding of both the environmental and cultural effects of this global event. 

Although a summer cooling trend over the past 8000 years is a logical consequence of Earth's orbital irregularities, resulting in a steady increase in Earth-Sun distance in Northern Hemisphere summer, and consequently general cooling over the past 8000 years.  However, the change in solar energy over the past millennium is small relative to the reconstructed LIA response. This raises compelling questions around what processes triggered the shift into the LIA following relatively warm Medieval times, and what ancillary processes plausibly allowed LIA cooling to persist for six centuries before warming again about the turn of the last century. Explanations for the LIA include explosive volcanism, sunspots, solar irradiance, and unforced natural variability.

In this symposium we take a broad geographic approach to understanding the human impacts of the LIA.  We have invited scholars who focus on Europe, the North American Southeast, the North American Southwest, and Asia.  Historic and archaeological records from these regions reveal significant social upheaval: abandonments, migration, crop failure, warfare, famine, and significant population losses.  We begin the process of linking these devastating episodes to the climatic events that may have caused them. 

Symposium Organizers: Prof. Gifford Miller and Prof. Catherine Cameron


-Full Symposium Program-

Keynote Speaker: Alan Robock: Climate Impacts of Explosive Volcanism

7 PM Friday, Nov. 3, Benson Earth Sciences Building Rm 180 - Free and Open to the Public - Light refreshments to follow

Dr. Alan Robock is Distinguished Professor in the Department of Environmental Sciences at Rutgers University and Associate Director of the Center for Environmental Prediction.  Dr. Robock's research spans the scope of climate science; from geoengineeringclimatic effects of nuclear weaponssoil moisture variationsthe effects of volcanic eruptions on climate, and the impacts of climate change on human activities. Of special interest here is his work on climate modeling and the impact of volcanic eruptions of climate and sea ice.

Saturday, Nov. 4:

8:30 AM to 5:30 PM, Benson Earth Sciences Building Rm 180/380 - Free and Open to the Public

Gifford Miller: Glaciers record onset of persistent LIA cold
Raymond Bradley: Climate of the Little Ice Age
Alexandra Jahn: Positive feedbacks from Arctic Ocean Sea Ice
Sam White: Cultural Impact of LIA cooling in Europe
Charles Cobb: Cultural impact of LIA cooling in SE USA
Scott Ortman: Mesa Verde at the start of the LIA
Aun Ali: Cultural impact of LIA cooling in Asia
Bette Otto-Bliesner: Explosive volcanism in a warming world

Relevant Publications:

Petersen, Kenneth Lee. "A warm and wet Little Climatic Optimum and a cold and dry Little Ice Age in the southern Rocky Mountains, USA.The Medieval Warm Period. Springer Netherlands, 1994. 243-269.

del Socorro Lozano-García, Ma, et al. "Tracing the effects of the Little Ice Age in the tropical lowlands of eastern Mesoamerica.Proceedings of the National Academy of Sciences 104.41 (2007): 16200-16203.

Bradley, R. S. and Jonest, P. D.: “Little Ice Age” summer temperature variations: their nature and relevance to recent global warming trends, The Holocene, 3(4), 367–376, doi:10.1177/095968369300300409, 1993.

Cobb, Charles R., and Brian M. Butler. "The vacant quarter revisited: late Mississippian abandonment of the Lower Ohio Valley." American Antiquity 67.4 (2002): 625-641.

Benson, Larry, et al. "Surface-exposure ages of Front Range moraines that may have formed during the Younger Dryas, 8.2 calka, and Little Ice Age events." Quaternary Science Reviews 26.11 (2007): 1638-1649.