Impacts of increasing drought on forest dynamics, structure, diversity, and management

Abstract

At the time of this writing in 2015, drought conditions have sustained over much of the continental United States for up to 4 years. Drought, a moisture limitation resulting from below average precipitation, high temperatures, or both, represents a departure from the "mean climate" of a region—and more frequent and severe droughts change this mean climate. Multi-year droughts have occurred throughout history (chapter 2); recent concern about prolonged drought has arisen because the increasing rainfall variation of recent decades (Janssen and others 2014, Li and others 2011) was a predicted consequence of greenhouse gas-driven warming (IPCC 1995, Overpeck and others 1990). While combined warming and variable precipitation have amplified forest drought severity in the last two decades (Allen and others 2015, Millar and Stephenson 2015) across the country (see text box below), the Western United States in particular has experienced numerous and widespread drought-related stand replacement events (e.g., Allen and others 2010, Breshears and others 2005, Ganey and Vojta 2011).

Parent Publication

• Effects of drought on forests and rangelands in the United States: a comprehensive science synthesis

Citation

Clark, James S.; Iverson, Louis; Woodall, Christopher W. 2016. Impacts of increasing drought on forest dynamics, structure, diversity, and management. In: Vose, James M.; Clark, James S.; Luce, Charles H.; Patel-Weynard, Toral, eds. Effects of drought on forests and rangelands in the United States: A comprehensive science synthesis. Gen. Tech. Rep. WO-93b. Washington, DC: U.S. Department of Agriculture, Forest Service, Washington Office: 59-96.