It's basic science that you learn in high school. Trees remove carbon from the air, and when they burn, that carbon dioxide is released back into the atmosphere.

Nevertheless, the US, the UK and the European Union (EU) continue to label the burning of wood as a "carbon-neutral" source of renewable energy on par with solar and wind power.

This "emissions loophole" is way more complicated and contentious than it may appear at first.

Some forest scientists think that the emissions from burning wood are balanced out when new trees are planted. Others think it will only exacerbate climate change.

But even though there is a clear need for more research and discussion, the EU and the US are moving forward with what they believe is a carbon neutral alternative to fossil fuels.

The little-known wood pellet industry is currently booming, and most of that demand is coming from the EU, where, in 2009, forest biomass was first given the label "carbon neutral."

The decision set off a domino effect, increasing electricity from biomass in the EU by 51 percent from 2009 to 2016. In 2015, the EU consumed 80 percent of the world's wood pellets, mostly for electricity production.

Today, the EU is leaning heavily on burning wood to meet its Paris carbon emission goals. In fact, it is their largest source of renewable energy, beating wind and solar.

In response, the US has become the EU's number one provider of wood pellets, sending almost a billion dollars of the stuff to Europe every year. The south-eastern region of the US produces 98 percent of all the exported pellets in America alone.

But while the EU and the US pin their hopes on this new industry, the environmental impact remains controversial and the jury is still out on whether burning wood can actually be considered "carbon neutral."

The argument goes that if you plant at least as many trees as you cut down, the carbon removed and then added into the atmosphere will all balance out in the end.

Proponents of the wood pellet industry argue that re-planting forests makes the practice renewable, while also encouraging landowners to replant trees and keep their forests healthy.

But while burning wood may be carbon neutral in some instances, like when businesses replant the same species of tree, in other instances it can actually be worse than coal.

Shipping wood pellets from the US to Europe uses a ton of energy, 25 percent of the total carbon emissions associated with biomass energy in Europe.

And some studies have also found that power plants fed by forest biomass contribute 15 to 20 percent more carbon dioxide than when they are fed by coal.

Plus, some scientists and environmentalists worry that unless the industry is heavily regulated, it will have a negative impact on biodiversity and carbon storage.

"The big problem is you're cutting old-growth forests and expecting them to regrow," said William Schlesinger, president emeritus of the Cary Institute of Ecosystem Studies and an EPA Science Advisory Board member.

"That's totally unrealistic in 20 years and not guaranteed over 100 years."

In other words, this practice is only sustainable on a long-term scale, and with climate change picking up steam, time is not something that the world has in spades.

Forests are home to huge amounts of CO2, stored in the wood and the soil. Burning that wood will obviously release greenhouse gases, but so too will exposing the soil, which holds twice the amount of CO2 that trees do.

And while some studies have estimated that the industry could lead to an increase in pine plantations, it was found that this will occur at the cost of natural timberland forests. In turn, research shows timber plantations do not store as much carbon as natural forests.

None of that research has convinced the US Environmental Protection Agency (EPA).

While the agency has failed to complete a full review of the matter, a memo published in 2012 determined that "it is not scientifically valid to assume that all biogenic feedstocks are carbon neutral" but that any such determination required further analysis.

Nevertheless, without further analysis, the administrator of the EPA Scott Pruitt announced in April 2018 that the agency would now label the burning of forest biomass as carbon neutral.

Some scientists say this is just another example of how Pruitt has placed industry interests over environmental considerations.

"Once again," said Sami Yassa, a scientist with the Natural Resources Defense Council (NRDC), "here [Pruitt is] dismissing established science to give a free pass to his industry pals to pollute."

Just this week, the EU announced that it would continue to label the burning of wood as "carbon neutral."

The announcement was made despite a warning from nearly 800 scientists, including winners of the Nobel Prize and the US Medal of Science.

The scientists cautioned that "the expansive eligibility for forest biomass in the EU's Renewable Energy Directive would likely lead to increases in greenhouse gas emissions for decades, quite plausibly lead to an additional harvest of wood equal to all of Europe's present harvest, and seriously threaten European and global forests."

If the EU is truly determined to meet its Paris emission goals, it needs to stop searching for loopholes and start adhering to the best and most robust science available.