Inhibitive Effects of Recent Exceeding Air Temperature Optima of Vegetation Productivity and Increasing Water Limitation on Photosynthesis Reversed Global Greening

Baozhang Chen, Yu Ke, Philippe Ciais, Zhenzhong Zeng, Andy Black, Honggang Lv, Mengtian Huang, Wenping Yuan, Xiangming Xiao, Junjun Fang, Kun Hou, Ying Ping Wang, Yiqi Luo

Research output: Contribution to journalArticlepeer-review

8 Scopus citations

Abstract

Global terrestrial vegetation dynamics have been rapidly altered by climate change. A widespread vegetation greenness over a large part of the planet from the 1980s to early this century has been reported, whereas weakening of CO2 fertilization effects and increasing climate extremes and the adverse impact of increasing rate of warming and severity of drought on vegetation growth were also reported. Earth system models project that the land carbon sink will decrease in size in response to an increase in warming during this century. How global vegetation is changing during this century in response to global warming and water availability across spatial and temporal scales remains uncertain. Our understanding of the widespread vegetation greening or browning processes and identifying the biogeochemical mechanisms remain incomplete. Here we use multiple long-term satellite leaf area index (LAI) records to investigate vegetation growth trends from 1982 to 2018. We find that the widespread increase of growing-season integrated LAI (greening) since 1980s was reversed (p-value < 0.05) around the year 2000 over 90% of the global vegetated area, and continued in only 10% of the global vegetated area. The reversal of greening trend was largely explained by the inhibitive effects of excessive optimal temperature on photosynthesis in most of the tropics and low latitudes, and by increasing water limitation (increasing in atmospheric vapor pressure deficit and decreasing in soil water availability) in the northern high latitudes (>45°N). Overall, the reversal of greening trend since 2000 weakened the negative feedback of carbon sequestration on the climatic system and should be considered in the strategies for climate warming mitigation and adaptation. Our findings of the diversity of processes that drive browning across bioclimatic-zones and ecosystems and of how those driving processes are changing would enhance our ability to project global future vegetation change and its climatic and abiotic consequences.

Original languageEnglish (US)
Article numbere2022EF002788
JournalEarth's Future
Volume10
Issue number11
DOIs
StatePublished - Nov 2022

Keywords

  • atmospheric vapor pressure deficit
  • global warming
  • optimum temperature for photosynthesis
  • reversal of greening trend
  • soil water availability
  • vegetation growth
  • water limitation

ASJC Scopus subject areas

  • General Environmental Science
  • Earth and Planetary Sciences (miscellaneous)

Fingerprint

Dive into the research topics of 'Inhibitive Effects of Recent Exceeding Air Temperature Optima of Vegetation Productivity and Increasing Water Limitation on Photosynthesis Reversed Global Greening'. Together they form a unique fingerprint.

Cite this