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  • The world is burning.

  • In California alone, some 3 million acres have burned since 2017.

  • Since the beginning of 2019, there have been more than 121,000 fires in

  • Brazil, and more than half of those have been in the Amazon rainforest.

  • These fires cost the planet trees, which help fight climate change.

  • The 2018 wildfire season in California is estimated to have released about

  • 68 million tons of carbon dioxide into the atmosphere.

  • That's roughly fifteen percent of all emissions in California.

  • In short, one of the world's best defenses against climate change is being

  • destroyed at an alarming rate.

  • A recent study from the Swiss Federal Institute for Technology, ETH

  • Zurich, says reforestation of forested lands at a global scale could help

  • capture atmospheric carbon and mitigate climate change.

  • According to the study, 0.9

  • billion hectares of land worldwide are available to be reforested and one

  • hectare is the equivalent of 2.47

  • acres. In short, 0.9

  • billion hectares is an area the size of the United States.

  • It's enough space to plant more than one trillion trees, and the resulting

  • carbon capture, according to the study, would be more than 200 gigatons.

  • That's about 32 percent of human carbon emissions since the beginning of

  • the industrial revolution.

  • In fact, after the study was first published, articles appeared with

  • headlines like 'Tree planting has mindblowing potential to tackle climate

  • change'. Simply put, trees capture carbon dioxide.

  • "My first reaction was, wow, wouldn't that be wonderful?

  • And actually, in a way, goes back to some earlier studies that show that,

  • you know, there are probably less than half the trees growing in the world

  • right now than we're growing, say, after the Ice Age retreated."

  • Bill Moomaw is professor emeritus of international environmental policy at

  • Tufts University.

  • He spent 20 years of his career looking at technological solutions to

  • climate change. A forest of 50-year-old oak trees, for example, would

  • absorb or sequester about 30000 pounds of CO2 per acre.

  • You've probably heard of the greenhouse effect.

  • It's what happens when heat radiating from earth gets trapped in the

  • atmosphere. "This isn't something that we're going to be seeing in the

  • distant future. Climate change is happening.

  • Humans are responsible for climate change and CO2 emissions that are

  • causing climate change to happen, along with emissions of methane from

  • agriculture and oil and gas activities.

  • To some extent, emissions of nitrous oxide gases that come from

  • agricultural practices primarily.

  • Certain gases exacerbate the problem, such as methane, nitrous oxide,

  • chlorofluorocarbons and of course, carbon dioxide.

  • Moomaw maintains that while planting trees is one part of the solution,

  • that alone won't stop climate change.

  • "We should simultaneously reduce our emissions as much as possible, as

  • rapidly as possible.

  • That means that the energy sector and the industrial sector into

  • agriculture and everything you can imagine."

  • NASA has several initiatives to track climate change or carbon

  • sequestration, the process of absorbing and storing carbon over a long

  • period of time. For example, the Global Ecosystem Dynamics Investigation

  • mission is a laser based on the International Space Station, one that

  • measures canopy height and forest structure around the world.

  • And there's also ICEsat, which measures the elevation of ice surfaces.

  • And there's Landsat, which monitors where deforestation or regrowth is

  • happening. While the evidence for climate change seems clear, there's no

  • consensus for how to deal with it.

  • Some have argued for carbon taxes, which would tax fossil fuels as a means

  • of reducing emissions.

  • Others have suggested a complete overhaul in agricultural and livestock

  • practices. But planting trees is something almost everyone can agree is

  • beneficial to the planet.

  • But would it really help fight climate change?

  • That part is far more controversial.

  • While the ETH Zurich study says there are 0.9

  • billion hectares of land available for planting, there is little chance

  • all of it will ever be used for that purpose.

  • Much of the available land is on private property, so private landowners

  • would have to be convinced to do the planting and a great deal of that

  • land is used for farming and grazing or beef cattle and dairy cows.

  • Reforestation also requires careful planning.

  • For example, too many trees in northern forests and warming could be

  • exacerbated. That's because too many trees block winter snows in winter

  • snows reflect sunlight.

  • At the same time, trees absorb the heat without redirecting it.

  • And that can create a local warming effect.

  • "Let's make sure we plant them in the right way.

  • Let's make some decisions about which species we're going to plant.

  • Let's not plant. Let's let's focus on on native species rather than

  • bringing in other species."

  • The Amazon rainforest is enormous.

  • It covers more than 2 million square miles, including a large chunk of

  • northwestern Brazil and extends to Peru, Colombia, Venezuela, Ecuador,

  • Bolivia, Guyana, French Guiana and Suriname.

  • Since January, more than 121,000 fires have ravaged Brazil, with more than

  • half of those burning in the country's Amazon rainforest.

  • Many of them were set as a result of slash and burn agriculture.

  • Farmers burned the land to create space for crops and grazing.

  • And it could get worse, especially under current President Jair

  • Bolsonaro's aggressive land use policies.

  • The country lost 53.8

  • million hectares of tree cover from 2001 to 2018.

  • That's a 10 percent decrease since 2000.

  • And deforestation is harmful in another way.

  • When a tree is cut down, it releases captured CO2 back into the

  • atmosphere. NASA estimates between 15 and 20 percent of carbon emissions

  • each year come from deforestation.

  • Much of the deforested lands in Brazil was planted over with soybeans or

  • used for cattle grazing.

  • About 80 percent of Amazon's deforestation is due to cattle ranching.

  • In fact, Brazil is now among the world's biggest soy and beef exporters.

  • Meanwhile, President Bolsonaro, who was a climate change skeptic, is not

  • inclined to stop deforestation anytime soon.

  • Since he took office, his administration has cut Brazil's Environmental

  • Protection Agency budget by 24 percent.

  • He's fired the director of the National Institute for Space Research, the

  • agency that tracks rainforest activity, and he's eliminated a number of

  • fines for environmental damage.

  • Still, earlier this year, Bolton R-OH told the U.N.

  • the Brazilian rainforest remains pristine and virtually untouched.

  • But really, Brazil lost more than five thousand two hundred square miles

  • of rainforest in 2018.

  • That's an area roughly the size of Connecticut.

  • Aside from saving the planet, there are sound fiscal reasons for planting

  • trees around the world. In 2015, Citigroup estimated the cost of not

  • taking action to fight climate change would be 44 trillion dollars by

  • 2016. Citigroup went on to say that incremental costs of action are

  • limited, offer reasonable returns on investment and should not have too

  • detrimental an effect on global growth.

  • Adding renewable energy and improving efficiency.

  • The study found, may actually boost the global economy.

  • There's also another issue to consider and that single use paper products,

  • paper napkins, tissues, diapers, toilet paper.

  • I mean, we're flushing we're flushing forests down the toilet.

  • Literally reinforce sustainability has even brought a number of new

  • business opportunities as well and range from one that manages sustainable

  • timber plantation to a company that works with smaller farmers to one that

  • sells beverages made from rainforest products.

  • BioCarbon engineering was started by a former NASA employee, Lauren

  • Fletcher. The company uses drone technology to reforest on a large scale

  • by firing seeds into the ground to people.

  • Planting trees can plants up to three thousand a day.

  • But a team operating 10 drones can plant up to 400,000.

  • The company estimated revenues for 2020 of nearly 100 million dollars.

  • Another called Guayaquil Sustainable Rainforest Products, has created a

  • market in the US around drink, made from here yerba mate a species from

  • the Holly family. The drink is popular in Paraguay, Chile, Uruguay and

  • southern Brazil and has been adapted to American tastes.

  • More than 600 social media stars recently raised over 16 million dollars

  • to plant trees all over the world.

  • The effort was spearheaded by YouTube star Jimmy Donaldson, who's also

  • known as Mr. Beast.

  • Donaldson post videos of stunts performed by himself and his friends.

  • Donaldson was challenged by a fan to plant 20 million trees.

  • It was part of the hashtag Team Trees Project.

  • The program raised over five million dollars in two days and all donations

  • went directly to the Arbor Day Foundation, a non-profit organization that

  • plants trees. Even Elon Musk committed to donating a million trees to the

  • project. The planting is slated to begin in January and should be finished

  • in three years. In July, Ethiopia planted more than 350 3 million trees in

  • just 12 hours.

  • The idea was to meet with the country calls its hashtag Green Legacy goal,

  • a program instituted by prime minister be met.

  • Ethiopia's efforts surpassed India's 2017 initiative, which planted 66

  • million trees in a single day.

  • There's also the bond challenge, which intends to plant 864 million acres

  • of trees by 2030.

  • And the Nature Conservancy has its own plant, a billion trees effort under

  • way. The program was launched in 2008 and it was originally intended to

  • bring back Brazil's Atlantic Forest.

  • It's since expanded to the U.S.,

  • Mexico and China.

  • And so what's needed is a comprehensive monitoring program where we can

  • look at the changes in land cover.

  • We can estimate the associated changes in carbon that's being removed from

  • the atmosphere and then scale this globally or over long periods of time.

  • Let's make sure that that carbon removal is permanent.

  • Reforestation efforts are also a major part of the Paris climate

  • agreement, which President Trump just formally moved to end U.S.

  • participation. The withdrawal will be complete at the end of 2020 in the

  • Paris Climate Agreement.

  • A handful of key countries, including Brazil, Indonesia, Peru and the

  • United States committed to intensifying efforts to protect forests because

  • while it doesn't take long to destroy forests, replacing them can take

  • decades. The most important thing is to slow down or stop deforestation

  • and conserve our existing forests.

  • The second is then to identify the areas that have been recently

  • deforested and go about restoring those ecosystems.

  • And then the third is to very carefully consider the forestation options

  • that are in the context of how those might affect land tenure,

  • biodiversity and food security.

The world is burning.

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種植數十億棵樹能阻止氣候變化嗎? (Can Planting Billions Of Trees Halt Climate Change?)

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    ayami 發佈於 2021 年 01 月 14 日
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