Timothy Ohlert, Melinda D. Smith, Scott L. Collins, Alan K. Knapp, Jeffrey S. Dukes, Osvaldo E. Sala, Kate Wilkins, Seth M. Munson, Maggie Anderson, Meghan L. Avolio, Anping Chen, Meghan T. Hayden, Martin C. Holdrege, Ingrid J. Slette, Peter A. Wilfahrt, Claus Beier, Lauchlan H. Fraser, Anke Jentsch, Michael E. Loik, Yiqi Luo, Fernando T. Maestre, Richard P. Phillips, Sally A. Power, Laura Yahdjian, Qiang Yu, Angel Chen, Andrew J. Felton, Laureano Gherardi, Nicholas J. Lyon, H Abdoli, Mehdi Abedi, Juan Alberti, Antonio I. Arroyo, Heidi Asbjornsen, Harald Auge, Seton Bachle, Michael Bahn, David C. Bartholomew, Amgaa Batbaatar, Taryn L. Bauerle, Karen H. Beard, Kai Behn, Ilka Beil, Lucio Biancari, Irmgard Blindow, Viviana F. Bondaruk, Elizabeth T. Borer, Edward W. Bork, Carlos Martín Bruschetti, Kerry Byrne, James F. Cahill, Dianela A. Calvo, Michele Carbognani, Cameron N. Carlyle, Karen Castillioni, Miguel Castillo-García, Manjunatha H. Chandregowda, Scott X. Chang, Jeff Chieppa, Amber C. Churchill, Marcus Vinícius Cianciaruso, Amanda L. Cordeiro, Sara A. O. Cousins, Daniela Cusack, Sven Dahlke, Pedro Daleo, Lee H. Dietterich, Maren Dubbert, Nico Eisenhauer, T’ai G. W. Forte, Flavia A. Funk, Darcy Galiano, Aaron C. Greenville, Liebao Han, Siri Vatsø Haugum, Yann Hautier, Andy Hector, Hugh A. L. Henry, Daniela Hoss, Forest Isbell, Samuel E. Jordan, Yuguang Ke, Eugene F. Kelly, Sally E. Koerner, Jüergen Kreyling, György Kröel‐Dulay, Alicia Kröpfl, Angelika Kübert, Andrew Kulmatiski, Eric G. Lamb, Klaus Steenberg Larsen, Steven R. Lee, Smriti Pehim Limbu, Anja Linstädter, Shirong Liu, Grisel Longo, Alejandro Loydi, Junwei Luan, Frederick Curtis Lubbe, Andrey V. Malyshev
As droughts become longer and more intense, impacts on terrestrial primary productivity are expected to increase progressively. Yet, some ecosystems appear to acclimate to multiyear drought, with constant or diminishing reductions in productivity as drought duration increases. We quantified the combined effects of drought duration and intensity on aboveground productivity in 74 grasslands and shrublands distributed globally. Ecosystem acclimation with multiyear drought was observed overall, except when droughts were extreme (i.e., ≤1-in-100-year likelihood of occurrence). Productivity losses after four consecutive years of extreme drought increased by ~2.5-fold compared with those of the first year. These results portend a foundational shift in ecosystem behavior if drought duration and intensity increase, from maintenance of reduced functioning over time to progressive and profound losses of productivity when droughts are extreme.