Fig. 1: Long-term trends of vegetation greenness, carbonate weathering intensity ([HCO3−] as a proxy), and the Weathering Sink for atmospheric CO2 (WSatm-CO2) in the carbonate areas of Southwest China and global carbonate areas during the past ~4 decades.
From: A greening Earth has reversed the trend of decreasing carbonate weathering under a warming climate
a Annual variations in mean normalized difference vegetation index (NDVI) in global carbonate areas during 1982–2018. b Location of the Southwest China carbonate areas. c Annual variations of normalized difference vegetation index (NDVI), net primary production (NPP, MUSES), and [HCO3−] in Southwest China. The curve of DICNPP is [HCO3−] simulated using a net primary productivity-based soil pCO2 model (NPP–pCO2) and a carbonate equilibrium model (MPD). The curve of DICNPP (FT) is [HCO3−] (DICNPP) with temperature fixed to the value in 1982, and DICNPP (FCO2) is [HCO3−] with pCO2 also fixed to the value in 1982. d Relationship between simulated values of [HCO3−] (DICNPP) and NDVI. e Variations in WSatm-CO2 and runoff depth (RF) in the carbonate areas of Southwest China during 1982–2018. The solid curve of WSatm-CO2 represents the Weathering Sink for atmospheric CO2 calculated by DICNPP in c and RF. The curve of WSatm-CO2 (FRF) is WSatm-CO2 with RF fixed to the value in 1982, and WSatm-CO2 (FDIC) is [HCO3−] fixed to the value in 1982. f Relationship between simulated WSatm-CO2 values and RF. The dashed lines in the c and e are the long-term linear trends (linear fitting line) of different parameters.
