It is believed to be the largest one-day mass planting in history, exceeding an effort in 2017 in India in which 1.5 million volunteers planted 66 million trees in just over 12 hours.
Ethiopia has joined 20 other African nations in a pledge to restore almost 400,000 square miles of forest on the continent. According to the United Nations, forest cover in Ethiopia has declined from 35 percent in the last century to just 4 percent today. The 426,000-square-mile country in the Horn of Africa plans to plant a total of 4 billion trees by the beginning of the rainy season in October. With a population of about 100 million people (including children), that goal would require every person in the country to plant at least 40 seedlings.
Government workers and students were given the day off to participate.
Earlier this month, a study published in the journal Science calculated that planting a forest nearly double the size of the United States could save the planet from the worst consequences of global warming. Those new forests would be capable of storing about 205 metric tons of carbon, which is roughly two-thirds of the excess carbon human beings have added to the atmosphere since the Industrial Revolution.
Reforestation has increasingly come to be seen as a means for addressing what scientists have begun calling a climate crisis caused by human carbon emissions.
In the United Kingdom, for example, government officials have estimated that the country will need to plant 1.5 billion trees if it hopes to reach its goal of becoming carbon neutral by 2050.
But setbacks to reforestation goals abound. In Brazil, President Jair Bolsonaro has reversed government protections of the Amazon rainforest, opening the region to development. Since Bolsonaro took office seven months ago, 1,330 square miles of forest cover have been lost, the New York Times reported.
Fifty years ago, the Amazon forest was itself as big in area as the lower 48 U.S. states. Since that time, it has been reduced by 16 percent, largely due to logging, PRI reported. Excess carbon in the atmosphere has also made equatorial forests less viable.
Whether tree planting can stay ahead of deforestation will help determine whether people can avert the worst consequences of global warming.
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