Aug 9, 2017

Global patterns of drought recovery

by
Christopher R. Schwalm, William R. L. Anderegg, Anna M. Michalak, Joshua B. Fisher, Franco Biondi, George Koch, Marcy Litvak, Kiona Ogle, John D. Shaw, Adam Wolf, Deborah N. Huntzinger, Kevin Schaefer, Robert Cook, et al
,
Nature
  • States that drought recovery time—how long an ecosystem requires to revert to its pre-drought functional state—is a critical metric of drought impact
  • States that the factors influencing drought recovery and its spatiotemporal patterns at the global scale are largely unknown
  • Analyzes three independent datasets of gross primary productivity and show that, across diverse ecosystems, drought recovery times are strongly associated with climate and carbon cycle dynamics, with biodiversity and CO2 fertilization as secondary factors
  • Finds that recovery is longest in the tropics and high northern latitudes (both vulnerable areas of Earth’s climate system)
  • Finds that drought impacts (assessed using the area of ecosystems actively recovering and time to recovery) have increased over the twentieth century
  • Concludes that if droughts become more frequent, as expected, the time between droughts may become shorter than drought recovery time, leading to permanently damaged ecosystems and widespread degradation of the land carbon sink