Increasing sensitivity of dryland vegetation greenness to precipitation due to rising atmospheric CO2
Year: 2022
Type: article
Abstract: Water availability plays a critical role in shaping terrestrial ecosystems, particularly in low- and mid-latitude regions. The sensitivity of vegetation growth to precipitation strongly regulates global vegetation dynamics and their responses to drought, yet sensitivity changes in response to climate change remain poorly understood. Here we use long-term satellite observations combined with a dynamic statistical learning approach to examine changes in the sensitivity of vegetation greenness to precipitation over the past four decades. We observe a robust increase in precipitation sensitivity (0.624% yr −1 ) for drylands, and a decrease (−0.618% yr −1 ) for wet regions. Using model simulations, we show that the contrasting trends between dry and wet regions are caused by elevated atmospheric CO 2 (eCO 2 ). eCO 2 universally decreases the precipitation sensitivity by reducing leaf-level transpiration, particularly in wet regions. However, in drylands, this leaf-level transpiration reduction is overridden at the canopy scale by a large proportional increase in leaf area. The increased sensitivity for global drylands implies a potential decrease in ecosystem stability and greater impacts of droughts in these vulnerable ecosystems under continued global change.
Source: Nature Communications
Institutions: Lawrence Berkeley National Laboratory, Peking University, University of California, Berkeley, Columbia University, National University of Singapore, The Ohio State University, Beijing Normal University, State Key Laboratory of Earth Surface Processes and Resource Ecology, Carnegie Institution for Science, Chapman University, Chinese Academy of Sciences, Institute of Tibetan Plateau Research
Language: English
Subfield: Ecology
Field: Environmental Science
Domain: Physical Sciences
SDGs: Climate action, Life on land
Open Access status: gold
Estimated APC paid: $5,890
Awards: G1286236842, G1632040200, G1863003419, G2596481784, G3083819904, EXTREME DROUGHT, HEAT AND WILDFIRE IMPACTS ON COASTAL WATER RELATIONS, PREEVENTS Track 2: Collaborative Research: Flash droughts: process, prediction, and the central role of vegetation in their evolution., G42916606, G4428998046, G4531314108, G465867758, G6439065178, G6483742305, G660579501, THIS PROJECT DIRECTLY ADDRESSES NASA'S TERRESTRIAL ECOLOGY PROGRAM STATED GOAL OF IMPROVING UNDERSTANDING OF THE STRUCTURE AND FUNCTION OF ECOSYSTEMS, G8794212055, G969889393
OpenAlex ID: W4292494039