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
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 geoengineering, climatic effects of nuclear weapons, soil moisture variations, the 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.
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
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