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For years， spring was known as the sandstorm season in Beijing， when dust and sand whipped up from the Gobi desert in the north by high winds enveloped the city， blotting out sunlight and forcing people to stay indoors. But in recent times， the menace has receded with an afforestation project started in 1978 beginning to produce results.
A Great Green Wall has been built under the Three-North Shelter Forest Program， a project to create strips of forests in north， northwest and northeast China to curb desert expansion and control sandstorm. Today， it is the largest man-made forest on earth.
Besides breaking wind and halting the encroaching desert， the afforestation campaign has also created another intangible benefit—carbon sequestration. By reducing the amount of carbon dioxide in the atmosphere， the forests have contributed to the global battle against climate change.
The afforestation drive is one of the pillars based on which President Xi Jinping made the commitment at the General Debate of the 75th Session of the UN General Assembly on September 22 that China would peak its carbon dioxide emissions before 2030 and achieve carbon neutrality before 2060.
To lend further support to the pledge， a key meeting of the Communist Party of China Central Committee in October laid down several new goals for sustainable development. The vision for 2035 includes promoting greener production methods and a green lifestyle in all sectors of society.
Carbon sinks are natural systems， mostly forests， water bodies and the soil， which absorb carbon dioxide from the atmosphere and store it. Rapid afforestation in Heilongjiang and Jilin provinces in northeast China， Yunnan and Guizhou provinces in the southwest and Guangxi Zhuang Autonomous Region in the south has enlarged the country’s carbon absorbing capacity. The article states that taken together， these areas account for over 35 percent of China’s entire land carbon sinks.
Though China is currently the largest emitter of carbon dioxide， it has also led the world in both the area and speed of afforestation. From 2000 to 2018， the global forest area decreased by 170，000 square km， while China’s forest area increased by 450，000 square km. The concentration of carbon dioxide in the atmosphere is the result of excess emissions of greenhouse gases unabsorbed by terrestrial and marine ecosystems. Though the ecosystems contribute greatly to carbon neutrality， there is still uncertainty regarding how to quantitatively evaluate it.
The latest research， involving forestry records and satellite remote-sensing measurements of vegetation， indicates that the underestimated forest carbon sinks of China will provide a strong scientific basis for China’s carbon neutral accounting.
“China is one of the major emitters of carbon dioxide in the world， but it is extremely uncertain how much of it is absorbed by forests，” Wang Jing， a co-author of the article， said. The new study examines how much carbon dioxide is absorbed by all the new trees during their growth.
Carbon neutrality or at least reduction in emissions has become critical due to the greenhouse gases’ impact on the global climate. Besides rising global temperature， extreme weather events have also been occurring with increasing frequency， posing a greater threat to human existence.
This year， south China suffered severe floods unseen in three decades while the U.S. faced one of its most active hurricane seasons on its southern and eastern coasts and record wildfires in its western states.
Carbon neutrality， or zero carbon dioxide emission， is a very ambitious target as most developed countries have a 50-70-year timetable to realize the state after their emissions peak.
For example， after years of emission reduction， the developed EU countries aim to be carbon-neutral by 2050. The largest economy， the U.S.， has so far not set any such goal. President Donald Trump has even described climate change as a hoax and pulled the U.S. out of the Paris Agreement on controlling global warming.
“The afforestation activities will play a role in achieving that [carbon-neutral] target，” Liu Yi， another co-author of the article， said.
Accelerating the development of a national carbon trading market is also important for reaching the goal of carbon neutrality， according to Wang. Technically， carbon neutrality can be achieved even if there are emissions. Globally， countries can neutralize their emissions by buying carbon credits from other countries that have less emission. Domestically， firms must either reduce their emissions or buy credits from those that produce fewer emissions. “China’s carbon market will evolve from regional pilot programs to a national trading scheme and expand from a single sector to multiple industries，” Li Gao， head of the Ministry of Ecology and Environment’s climate change office， said on October 28， indicating China plans to launch a nationwide emission trading scheme in the next five years.
However， “a massive change in energy production and also the growth of sustainable land carbon sinks” are essential for carbon neutrality， Liu said.
Reducing the use of fossil fuels， and improving the development of clean energy and the carbon trading market mechanism are three main approaches， Wang Ruibin， an associate research fellow with the China Institute of International Studies， told Beijing Review.
China， the largest consumer of coal， has painstakingly reduced its coal consumption in recent years. Coal’s share in total energy consumption dropped from 70.2 percent in 2011 to 57.7 percent in 2019.
As for renewable energy， China has taken a lead and is now the world’s largest producer， exporter and installer of solar panels， wind turbines， batteries and electric vehicles. From 2011 to 2019， the percentage of renewable energy in its energy mix increased from 13 percent to 23.4 percent.
To further increase the share of renewables， some technical issues have to be resolved， according to Wang Ruibin. For example， wind power suffers from fluctuations in generation， which depends on the strength of the wind. Short-term power variations can cause voltage fluctuations in the power grid， ultimately damaging sensitive electrical equipment.
Recycling solar panels is another issue to address. The International Renewable Energy Agency estimates that by 2050， up to 78 million tons of solar panels will have reached the end of their life. If not properly disposed of， they will cause an environmental hazard.
So going forward， Wang Ruibin’s suggestion is that research and development as well as technological international cooperation be enhanced.
A Great Green Wall has been built under the Three-North Shelter Forest Program， a project to create strips of forests in north， northwest and northeast China to curb desert expansion and control sandstorm. Today， it is the largest man-made forest on earth.
Besides breaking wind and halting the encroaching desert， the afforestation campaign has also created another intangible benefit—carbon sequestration. By reducing the amount of carbon dioxide in the atmosphere， the forests have contributed to the global battle against climate change.
The afforestation drive is one of the pillars based on which President Xi Jinping made the commitment at the General Debate of the 75th Session of the UN General Assembly on September 22 that China would peak its carbon dioxide emissions before 2030 and achieve carbon neutrality before 2060.
To lend further support to the pledge， a key meeting of the Communist Party of China Central Committee in October laid down several new goals for sustainable development. The vision for 2035 includes promoting greener production methods and a green lifestyle in all sectors of society.
An undervalued role
The sequestration effect of carbon sinks in northeast and southwest China has been underestimated due to rapid afforestation， according to an article published in the British science magazine Nature on October 28. It notes that between 2010 and 2016， land biosphere carbon sinks in China absorbed about 45 percent of the country’s estimated carbon dioxide emissions from domestic human activities during that period.Carbon sinks are natural systems， mostly forests， water bodies and the soil， which absorb carbon dioxide from the atmosphere and store it. Rapid afforestation in Heilongjiang and Jilin provinces in northeast China， Yunnan and Guizhou provinces in the southwest and Guangxi Zhuang Autonomous Region in the south has enlarged the country’s carbon absorbing capacity. The article states that taken together， these areas account for over 35 percent of China’s entire land carbon sinks.
Though China is currently the largest emitter of carbon dioxide， it has also led the world in both the area and speed of afforestation. From 2000 to 2018， the global forest area decreased by 170，000 square km， while China’s forest area increased by 450，000 square km. The concentration of carbon dioxide in the atmosphere is the result of excess emissions of greenhouse gases unabsorbed by terrestrial and marine ecosystems. Though the ecosystems contribute greatly to carbon neutrality， there is still uncertainty regarding how to quantitatively evaluate it.
The latest research， involving forestry records and satellite remote-sensing measurements of vegetation， indicates that the underestimated forest carbon sinks of China will provide a strong scientific basis for China’s carbon neutral accounting.
“China is one of the major emitters of carbon dioxide in the world， but it is extremely uncertain how much of it is absorbed by forests，” Wang Jing， a co-author of the article， said. The new study examines how much carbon dioxide is absorbed by all the new trees during their growth.
Carbon neutrality
Carbon neutrality or at least reduction in emissions has become critical due to the greenhouse gases’ impact on the global climate. Besides rising global temperature， extreme weather events have also been occurring with increasing frequency， posing a greater threat to human existence.
This year， south China suffered severe floods unseen in three decades while the U.S. faced one of its most active hurricane seasons on its southern and eastern coasts and record wildfires in its western states.
Carbon neutrality， or zero carbon dioxide emission， is a very ambitious target as most developed countries have a 50-70-year timetable to realize the state after their emissions peak.
For example， after years of emission reduction， the developed EU countries aim to be carbon-neutral by 2050. The largest economy， the U.S.， has so far not set any such goal. President Donald Trump has even described climate change as a hoax and pulled the U.S. out of the Paris Agreement on controlling global warming.
“The afforestation activities will play a role in achieving that [carbon-neutral] target，” Liu Yi， another co-author of the article， said.
Accelerating the development of a national carbon trading market is also important for reaching the goal of carbon neutrality， according to Wang. Technically， carbon neutrality can be achieved even if there are emissions. Globally， countries can neutralize their emissions by buying carbon credits from other countries that have less emission. Domestically， firms must either reduce their emissions or buy credits from those that produce fewer emissions. “China’s carbon market will evolve from regional pilot programs to a national trading scheme and expand from a single sector to multiple industries，” Li Gao， head of the Ministry of Ecology and Environment’s climate change office， said on October 28， indicating China plans to launch a nationwide emission trading scheme in the next five years.
However， “a massive change in energy production and also the growth of sustainable land carbon sinks” are essential for carbon neutrality， Liu said.
Reducing the use of fossil fuels， and improving the development of clean energy and the carbon trading market mechanism are three main approaches， Wang Ruibin， an associate research fellow with the China Institute of International Studies， told Beijing Review.
China， the largest consumer of coal， has painstakingly reduced its coal consumption in recent years. Coal’s share in total energy consumption dropped from 70.2 percent in 2011 to 57.7 percent in 2019.
As for renewable energy， China has taken a lead and is now the world’s largest producer， exporter and installer of solar panels， wind turbines， batteries and electric vehicles. From 2011 to 2019， the percentage of renewable energy in its energy mix increased from 13 percent to 23.4 percent.
To further increase the share of renewables， some technical issues have to be resolved， according to Wang Ruibin. For example， wind power suffers from fluctuations in generation， which depends on the strength of the wind. Short-term power variations can cause voltage fluctuations in the power grid， ultimately damaging sensitive electrical equipment.
Recycling solar panels is another issue to address. The International Renewable Energy Agency estimates that by 2050， up to 78 million tons of solar panels will have reached the end of their life. If not properly disposed of， they will cause an environmental hazard.
So going forward， Wang Ruibin’s suggestion is that research and development as well as technological international cooperation be enhanced.