How Effective Are Tropical Forests at Absorbing Carbon?

The Earth’s army of roughly three trillion trees has helped to regulate our climate for millennia by sucking up carbon dioxide from the air and turning it into oxygen. But the tide is turning, and the planet’s dwindling tropical forests can’t keep up -- to the point where the Earth’s forests now emit almost twice as much carbon as they consume. In 2017, scientists from Boston University and the Woods Hole Research Center reported these grim facts, warning readers that “we need to drastically reduce emissions and greatly increase forests' ability to absorb and store carbon” in order to keep global temperatures from rising to dangerous levels.

Don't say you weren't warned:

• The researchers said that ending deforestation practices in the tropics could reduce global carbon emissions by 8 percent, but that there’s a limited window of opportunity to reverse the trend.
• Around 20% of the Amazon rainforest has been destroyed in recent years. Satellite images and laser technology were used to record how vast areas of forest have been lost since 2003.
• The study found that the tropics now contribute more carbon to the atmosphere than they take in -- 862 teragrams of carbon are emitted while only 437 teragrams are consumed.

Frequently Asked Questions

How much carbon can tropical forests absorb compared to other ecosystems?

Tropical forests are among the most efficient carbon sinks on the planet. They can absorb about 1.4 billion metric tons of carbon dioxide annually, according to the Rainforest Alliance. This is significantly higher than temperate forests due to their larger biomass and faster growth rates.

What role do tropical forests play in mitigating climate change?

Tropical forests play a crucial role in mitigating climate change by absorbing vast amounts of carbon dioxide from the atmosphere, which helps to offset greenhouse gas emissions. They store carbon in their vegetation and soil, acting as a buffer against the increasing concentration of CO2, which is a primary driver of global warming.

Are all tropical forests equally effective at carbon absorption?

No, the effectiveness of carbon absorption in tropical forests varies depending on factors such as forest age, health, and biodiversity. Primary forests, which are undisturbed and mature, typically store more carbon than secondary forests or those recovering from disturbance. The presence of diverse species also contributes to more robust carbon storage capabilities.

How does deforestation affect the carbon-absorbing abilities of tropical forests?

Deforestation severely undermines the carbon-absorbing abilities of tropical forests. When trees are cut down, they release the carbon they've stored back into the atmosphere. The World Resources Institute states that tropical deforestation contributes about 10% of global greenhouse gas emissions, thereby exacerbating climate change.

Can reforestation of tropical areas restore carbon absorption to original levels?

Reforestation can help restore carbon absorption, but it may not immediately return to original levels. Young, regrowing forests typically absorb carbon at a faster rate than mature forests, but it takes decades for them to develop the same carbon storage capacity as old-growth forests. Biodiversity and ecosystem complexity also take time to recover.

What is the future outlook for tropical forests' carbon absorption capabilities?

The future outlook is uncertain and hinges on human actions. If current rates of deforestation continue, tropical forests' ability to absorb carbon will be significantly diminished. However, with effective conservation efforts and sustainable land-use practices, tropical forests can continue to be a vital carbon sink. International initiatives like REDD+ aim to incentivize forest conservation to maintain and enhance carbon absorption.