Modern climate change is a worldwide political issue and a constant topic of research and debate. But climatic cycles are well documented in Europe over the past 3,000 years, and archaeologists are using new technologies to study them in North America. In this volume historian William Foster assembles current research to examine the impact of climate cycles on the history of the American Southwest, Southern Plains, and Southeast.
A number of scholars make a strong case that the well-documented Medieval Warm Period (MWP) ca. A.D. 900 to 1300 and the Little Ice Age (LIA) ca. A.D. 1300-1600 had substantial impacts on economic and cultural life in Europe. Foster makes a similar case for North America. He follows the rise of three important cultural centers—Chaco Canyon in New Mexico, Cahokia near St. Louis, and Casas Grandes in northern Chihuahua—during the warm and moist years of the MWP. With the onset of the LIA around A.D. 1300, these centers faced a marked decline in population and agricultural production. The major centers collapsed, as did dozens of smaller towns. As in Europe, Foster argues, climate had a major impact on native cultures.
In 2006 the National Research Council (NRC), the research and operating arm of the National Academy of Science, published a report on surface temperatures over the past 2,000 years. This report is a primary source for Foster’s study, as is the research of archaeologists who use modern techniques to reconstruct ancient climates, including tree ring and ice core data, glacial records, and marine and other sediment studies.
Climate changes, both big and small, are a growing area of investigation for archaeologists. If they can accurately reconstruct ancient climates, it may well lead to important revelations about prehistoric societies. Yet ecological determinists like Foster and Jarred Diamond may suffer the fate of most single cause theorists. Nonetheless, Foster makes a powerful case for more study of the role of climate in North America prehistory.
