Effect of terrestrial vegetation growth on climate change in China

Long Li; Yong Zha; Jiahua Zhang; Yunmei Li; Heng Lyu

doi:10.1016/j.jenvman.2020.110321

Effect of terrestrial vegetation growth on climate change in China

J Environ Manage. 2020 May 15:262:110321. doi: 10.1016/j.jenvman.2020.110321. Epub 2020 Feb 28.

Authors

Long Li¹, Yong Zha², Jiahua Zhang³, Yunmei Li¹, Heng Lyu¹

Affiliations

¹ Key Laboratory of Virtual Geographic Environment of Ministry of Education, Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, College of Geographic Science, Nanjing Normal University, Nanjing, 210023, China.
² Key Laboratory of Virtual Geographic Environment of Ministry of Education, Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, College of Geographic Science, Nanjing Normal University, Nanjing, 210023, China. Electronic address: yzha@njnu.edu.cn.
³ Institute of Remote Sensing and Digital Earth, Chinese Academy of Sciences, Beijing, 100094, China.

PMID: 32250804
DOI: 10.1016/j.jenvman.2020.110321

Abstract

Globally, some vegetation has grown significantly over the past decades, but the climate benefits remain unclear, especially in the temperate regions. Understanding the biophysical effects and identifying the potential of vegetation will help to mitigate climate change. Here, we propose a vegetation-adjusted temperature index to understand how terrestrial vegetation growth in China affects the air temperature for 2001-2013, based on satellite-derived normalized difference vegetation index, near-surface air temperature (T_a) and the land surface temperature. Grassland growth and cropland growth are found to cool the T_a by -0.08 ± 0.32 °C (mean ± one standard deviation) and -0.06 ± 0.28 °C, respectively. Forest growth results in net climate warming by 0.05 ± 0.29 °C. Biophysical effects, elevation and background climate are used to explain the climate impacts of vegetation. Results show that the biophysical effects dominate the climate impact. More specifically, evapotranspiration (ET) controls the daytime climate impact, and at night, an indirect effect of albedo (the release of daytime heat storage) dominates it. Lower precipitation, temperature and elevation reinforce the warming potential. Moreover, the effects of albedo and ET on climate are nonlinear. During the day, although lower albedo absorbs more incoming radiation, it releases more extra heat per unit ET that can compensate for the increased incoming radiation. At night, the warming effect reflects the release of daytime heat storage. Overall, tropical vegetation growth (-0.04 ± 0.10 °C) and warm temperate vegetation growth (-0.08 ± 0.15 °C) achieve the climatic benefits. Overall, the method proposed contributes to quantitatively evaluate the role of afforestation plan on regional climate cooling, and provides some policy/practical implications for future afforestation projects. Future afforestation projects should carefully consider the biophysical process and background climate to mitigate climate change.

Keywords: Biophysical effects; Climate mitigation; MODIS; Remote sensing; Terrestrial vegetation; VATI.

MeSH terms

China
Climate Change*
Forests*
Temperature