A study led by the Max Planck Institute for Biogeochemistry, USGS, and colleagues found that 70% of extreme vegetation declines are linked with five types of climate extremes. This work is one of the first global analyses to associate vegetation decline events with diverse climatic extremes.
Global vegetation decline is linked with multiple climate extremes
Extreme negative anomalies of vegetation growth (vegetation declines, or NEGs) have been found to be associated with climate extremes, and can indicate impaired ecosystem services.
Most of the previous research on “extremes” focused on evaluating climate extremes and their potential impacts. However, a vegetation-oriented analysis complements the widely used climate-oriented approach and deepens understanding of the causes and consequences of extreme vegetation responses.
Until this study, the relationship between NEGs and multiple climate extremes (frost, heatwave, soil drought, atmospheric drought, flood) remained somewhat unknown at regional and global scales.
This research used satellite-derived vegetation index data (NDVI) and tree-ring chronologies to identify periods of NEGs from 1981-2015 across the global land surface.
Researchers found 70% of reductions in vegetation growth can be attributed to 5 types of climate extremes or co-occurring climate extremes. The relationship between NEGs and climate extremes varies by biome and region.
Droughts and drought-related climate extremes (with high vapor deficit and/or heatwave) are primarily responsible for most NEGs observed in the wet tropics, arid and semi-arid regions, while NEGs in mountain and high latitude regions of North America, Europe, and Siberia are associated with cold extremes, hydrological wet extremes, or their co-occurrence.
An improved understanding of the climate extremes that are responsible for extreme vegetation declines helps to provide reliable projections of risks and informs future ecosystem science, public-policy decisions, and adaptation strategies.
Read the paper: Yang, H., Munson, S.M., Huntingford, C., Carvalhais, N., Knapp, A.K., Li, X., Peñuelas, J., Zscheischler, J., and Chen, A., 2023, The detection and attribution of extreme reductions in vegetation growth across the global land surface: Global Change Biology, v. 29, no. 8, p. 2351-2362, https://doi.org/10.1111/gcb.16595.
Nature Climate Change also highlighted the research in a blog, "Climate extremes drive negative vegetation growth": https://doi.org/10.1038/s43017-023-00392-2.