Albedo-dominated biogeophysical warming effects induced by vegetation restoration on the Loess Plateau, China

Vegetation restoration can reduce surface albedo and retain more heat on the land surface. This feedback would partially offset the cooling effect of vegetation by absorbing CO2. Ignoring the climate feedback from changes in albedo will lead us to overestimate the contribution of increased vegetation to warming mitigation. Utilizing remote sensing data and employing a radiative forcing algorithm, we quantified the climatic feedback associated with vegetation restoration on the Chinese Loess Plateau (CLP). The surface albedo on the CLP decreased from 2001 to 2017, correlating with increased vegetation greenness, resulting in positive radiative forcing (multi-year average: 1.58 W/m2, average growth rate: 0.125 W/m2/yr). The radiative feedback of reduced albedo due to vegetation restoration is equivalent to the warming effect of emitting 3.7 kgCO2/m2. Contrary to expectations, CLP vegetation restoration efforts lacked a significant cooling effect, potentially increasing surface warming risks from albedo changes. These results emphasize the dominant role of biogeophysical feedback mechanisms induced by vegetation restoration. It will contribute to a comprehensive assessment of the climate benefits of large-scale vegetation increases in temperate regions. Decision makers can provide diverse vegetation man-agement and restoration strategies depending on the differences in climate feedback for vegetation restoration at different locations.

Automated summary

Vegetation restoration reduces surface albedo and retains more heat, partially offsetting the cooling effect by absorbing CO2. Ignoring the climate feedback from albedo changes overestimates the contribution of increased vegetation in mitigating warming. A study on the Chinese Loess Plateau quantified the climatic feedback of vegetation restoration, showing a positive radiative forcing and an equivalent warming effect of emitting CO2.