China is responsible for around 28% of global emissions, making it the world’s most significant source of human-produced carbon dioxide. To abate its climate impacts, the country has an aggressive tree-planting policy, absorbing a significantly higher amount of CO2 than previously expected.
Recently the government proclaimed intent to peak emissions before the end of the decade and become carbon neutral by 2060. The specifics of how it plans to achieve this are unclear; however, it will inevitably involve slashing fossil fuel use and methods of pulling carbon out of the atmosphere. One such way is reforestation, and they’re doing a good job so far with it.
An international team has been studying tree coverage in China. They found two areas (which include the provinces of Yunnan, Guizhou, Guangxi, Heilongjiang, and Jilin) where the scale of CO2 absorption by virgin forests has been underestimated.
The areas combined account for around 35% of the country’s entire land carbon sink – any reservoir (peatland, forest, etc.) that absorbs more carbon than it releases, thus lowering the carbon concentration in the atmosphere.
Co-author Professor Yi Liu, from the Chinese Academy of Sciences’ Institute of Atmospheric Physics (IAP) in Beijing, told BBC News:
Achieving China’s net-zero target by 2060, recently announced by the Chinese President Xi Jinping, will involve a massive change in energy production and also the growth of sustainable land carbon sinks. The afforestation activities described in [our Nature] paper will play a role in achieving that target.
In recent decades, billions of trees have been planted to tackle soil loss and desertification and establish booming paper and timber industries. The study analyzed how much carbon these new trees are sequestering as they grow through ground and satellite observations.
The researchers used a host of data sources, including forestry records, soil water availability, satellite remote-sensing measurements of vegetation greenness, and observations of CO2 from both direct sampling of the air at ground level and space using satellites.
Professor Shaun Quegan from Sheffield University, who studies Earth’s carbon balance but was not involved in this study, said:
The extent of the northeast sink was not a surprise to me, but the southwest one was. But new forests’ ability to draw down carbon declines with time as the growth rate declines and the systems move towards a steadier state. This paper clearly illustrates how multiple sources of evidence from space data can increase our confidence in carbon flux estimates based on sparse ground data. This augurs well for the use of the new generation of space sensors to aid nations’ efforts to meet their commitments under the Paris Agreement.
While it’s fantastic news that China’s forests are absorbing more carbon than thought, the country still has a ways to go to reduce the monstrous amount of emissions it produces yearly. Planting a bunch of trees won’t be enough to reach its climate goals.
