Defining Ecological Drought for the Twenty-First Century

Authors

Shelley D. Crausbay, University of California, Santa BarbaraFollow
Aaron R. Ramirez, University of California, Santa BarbaraFollow
Shawn L. Carter, USGS
Molly S. Cross, Wildlife Conservation Society
Kimberly R. Hall, The Nature ConservancyFollow
Deborah J. Bathke, University of Nebraska-LincolnFollow
Julio L. Betancourt, USGS
Steve Colt, Alaska Pacific University
Amanda E. Cravens, USGS
Melinda S. Dalton, USGS
Jason B. Dunham, USGS
Lauren E. Hay, USGS
Michael J. Hayes, University of Nebraska - LincolnFollow
Jamie McEvoy, Montana State University
Chad A. McNutt, University Corporation for Atmospheric Research
Max A. Moritz, University of California - Berkeley
Keith H. Nislow, University of Massachusetts Amherst
Nejem Raheem, Emerson College
Todd Sanford, Climate Central

Document Type

Article

Date of this Version

2017

Citation

AMERICAN METEOROLOGICAL SOCIETY BAMS

Comments

© 2017 American Meteorological Society

DOI:10.1175/BAMS-D-16-0292.1

Abstract

THE RISING RISK OF DROUGHT. Droughts of the twenty-first century are characterized by hotter temperatures, longer duration, and greater spatial extent, and are increasingly exacerbated by human demands for water. This situation increases the vulnerability of ecosystems to drought, including a rise in drought-driven tree mortality globally (Allen et al. 2015) and anticipated ecosystem transformations from one state to another—for example, forest to a shrubland (Jiang et al. 2013). When a drought drives changes within ecosystems, there can be a ripple effect through human communities that depend on those ecosystems for critical goods and services (Millar and Stephenson 2015). For example, the “Millennium Drought” (2002–10) in Australia caused unanticipated losses to key services provided by hydrological ecosystems in the Murray–Darling basin—including air quality regulation, waste treatment, erosion prevention, and recreation. The costs of these losses exceeded AUD $800 million, as resources were spent to replace these services and adapt to new drought-impacted ecosystems (Banerjee et al. 2013). Despite the high costs to both nature and people, current drought research, management, and policy perspectives often fail to evaluate how drought affects ecosystems and the “natural capital” they provide to human communities. Integrating these human and natural dimensions of drought is an essential step toward addressing the rising risk of drought in the twenty-first century.