Contrasting temperature effects on the velocity of early- versus late-stage vegetation green-up in the Northern Hemisphere
Songbai Hong
Sino-French Institute for Earth System Science, College of Urban and Environmental Sciences, Peking University, Beijing, China
Search for more papers by this authorYichen Zhang
Sino-French Institute for Earth System Science, College of Urban and Environmental Sciences, Peking University, Beijing, China
Search for more papers by this authorYitong Yao
Laboratoire des Sciences du Climat et de l'Environnement, LSCE/IPSL, CEA-CNRS-UVSQ, Université Paris-Saclay, Gif-sur-Yvette, France
Search for more papers by this authorFandong Meng
Sino-French Institute for Earth System Science, College of Urban and Environmental Sciences, Peking University, Beijing, China
Search for more papers by this authorQian Zhao
Sino-French Institute for Earth System Science, College of Urban and Environmental Sciences, Peking University, Beijing, China
Search for more papers by this authorCorresponding Author
Yao Zhang
Sino-French Institute for Earth System Science, College of Urban and Environmental Sciences, Peking University, Beijing, China
Correspondence
Yao Zhang, Sino-French Institute for Earth System Science, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China.
Email: zhangyao@pku.edu.cn
Search for more papers by this authorSongbai Hong
Sino-French Institute for Earth System Science, College of Urban and Environmental Sciences, Peking University, Beijing, China
Search for more papers by this authorYichen Zhang
Sino-French Institute for Earth System Science, College of Urban and Environmental Sciences, Peking University, Beijing, China
Search for more papers by this authorYitong Yao
Laboratoire des Sciences du Climat et de l'Environnement, LSCE/IPSL, CEA-CNRS-UVSQ, Université Paris-Saclay, Gif-sur-Yvette, France
Search for more papers by this authorFandong Meng
Sino-French Institute for Earth System Science, College of Urban and Environmental Sciences, Peking University, Beijing, China
Search for more papers by this authorQian Zhao
Sino-French Institute for Earth System Science, College of Urban and Environmental Sciences, Peking University, Beijing, China
Search for more papers by this authorCorresponding Author
Yao Zhang
Sino-French Institute for Earth System Science, College of Urban and Environmental Sciences, Peking University, Beijing, China
Correspondence
Yao Zhang, Sino-French Institute for Earth System Science, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China.
Email: zhangyao@pku.edu.cn
Search for more papers by this author
Abstract
Global vegetation greening has been widely confirmed in previous studies, yet the changes in the velocity of green-up in each month of green-up period (GUP) remains unclear. Here, we defined the velocity of vegetation green-up as VNDVI (the monthly increase of Normalized Difference Vegetation Index [NDVI] during GUP) and further explored its response to climate change in middle-high-latitude Northern Hemisphere. We found that in early GUP, VNDVI generally showed positive trends from 1982 to 2015, whereas in late GUP, it showed negative trends in most areas. Such contrasting trends were mainly due to a positive temperature effect on VNDVI in early GUP, but this effect turned negative in late GUP. The increase of soil moisture also in part explained the accelerated vegetation green-up, especially in the arid and semi-arid ecosystems of inland areas. Our analyses also indicate that the first month of the GUP was the key stage impacting vegetation greenness in summer. Future warming may continuously speed up the early growth of vegetation, altering the seasonal trajectory of vegetation and its feedbacks to the Earth system.
CONFLICT OF INTEREST
The authors declare no competing interests.
DATA AVAILABILITY STATEMENT
All data used in this study are openly available from the following: GIMMS NDVI are available at http://poles.tpdc.ac.cn/en/data/9775f2b4-7370-4e5e-a537-3482c9a83d88/. CRU air temperature is available at https://crudata.uea.ac.uk/cru/data/hrg/cru_ts_4.05/cruts.2103051243.v4.05/; C3S soil moisture is available at https://cds.climate.copernicus.eu/cdsapp#!/dataset/satellite-soil-moisture?tab=overview; CRU-JRA v2.2 solar radiation is available at https://catalogue.ceda.ac.uk/uuid/7f785c0e80aa4df2b39d068ce7351bbb. MODIS EVI is available at https://lpdaac.usgs.gov/products/mod13c2v006/. All computer codes used in this study are available from the corresponding author upon reasonable request.
Supporting Information
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Figure S1 |
Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.
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- National Key Research and Development Program of China. Grant Number: 2019YFA0607304
- National Natural Science Foundation of China. Grant Number: 42141005
- Postdoctoral Innovation Talents Support Program of China. Grant Number: BX2021005
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