News Brief
August 16, 2017 
RICHLAND, Wash. - As global temperatures continue to rise, droughts will become more frequent in many regions. A new study in the journal Nature has found that ecosystems are taking progressively longer to recover from droughts. Incomplete drought recovery may become the new normal in some areas, possibly leading to increased tree death and emissions of greenhouse gases.
Led by Christopher Schwalm of the Woods Hole Research Center, researchers from 17 institutions including the D.O.E.'s Pacific Northwest National Lab used remote sensing, field data and Earth system modeling to measure recovery time following droughts in various regions of the world.
PNNL's Maoyi Huang modeled droughts and ecosystem recovery using an Earth system model. The team combined her model results with other models and data from short-term ground and satellite observations to re-create conditions in the last century. The team found that the frequency of six-month recovery times dropped while two-year recovery times in excess of doubled from the early 20th century to the end of it.
Drought recovery times in 2 particular regions, the tropics and the northern high latitudes, were longer than in others. Overall, the results suggest that, in some areas, if the frequency of droughts increases, the time between droughts likely won't be long enough for trees to recover. That could lead to vegetation taking up lower amounts of carbon out of the air.
Read more in these stories at Woods Hole Research Center or Carnegie Science.
REFERENCE: C.R. Schwalm, W.R.L. Anderegg, A.M. Michalak, J.B. Fisher, F. Biondi, G. Koch, M. Litvak, K. Ogle, J.D. Shaw, A. Wolf, D.N. Huntzinger, K. Schaefer, R. Cook, Y. Wei, Y. Fang, D. Hayes, M. Huang, A. Jain, , and H. Tian. 2017. Global patterns of drought recovery. Nature. DOI: 10.1038/nature23021.
Tags: Environment, Fundamental Science, Climate Science, Atmospheric Science
Interdisciplinary teams at Pacific Northwest National Lab address many of America's most pressing issues in energy, the environment and national security through advances in basic and applied science. Founded in 1965, PNNL employs 4,400 staff and has an yearly budget of nearly $1 billion. It is managed by Battelle for the D.O.E.'s Office of Science. As the single biggest supporter of basic research in the physical sciences in the United States, the Office of Science is working to address some of the most pressing challenges of our time. For more information on PNNL, visit the PNNL News Center, or follow PNNL on Facebook, Google+, Instagram, LinkedIn and Twitter.
